What's new inGenes and MemesNote: Newest contributions are at the top! |
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Year 2008 |
Crying and screaming cells and magnetic bodies expressing their emotions
By using nanotechnological methods James Gimzewski [3], his student Andrew Pelling and collaborators discovered that the cell walls of bacterium Saccharomyces cerevisiae perform periodic motion with amplitude about 3 nm in the frequency range .8-1.6 kHz (one octave) [2]. Or more concretely, bacteria produce sounds audible to humans with average frequency of 1 kHz in a range of one octave. The frequency has strong temperature dependence, which suggests a metabolic mechanism. From the temperature dependence one deduces the activation energy to be 58 kJ/mol, which is consistent with the cell's metabolism involving molecular motors such as kinesin, dynein, and myosin. The magnitude of the forces observed (10 nN) suggests concerted nanomechanical activity is operative in the cell. From less formal popular articles [4] one can learn that it is difficult to avoid the impression that intelligent communication is in question. Dying cells produce a characteristic screaming sound. One can also distinguish between normal cells and cancel cells on basis of the sound they produces as well as between mammalian and bacterial cells. What might be the explanation of these findings in TGD framework?
References[1] The chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer of "Genes and Memes". [2] Pelling et al (2004), Local Nanomechanical Motion of the Cell Wall of Saccharomyces cerevisiae, Science 20 August: Vol. 305. no. 5687, pp. 1147 - 1150. [] [3] James Gimzewski. [4] A. Goho (2004), Rattle and Hum: molecular machinery makes yeast cells purr. Science News, August 21.M. Wheeler, (2004) Signal Dicovery?, Smithsonian Magazine. March issue. M. Wertheim (2003), Bucky Balls and Screeming Cells:the amazing miniature world of UCLA chemist Jim Gimzewski, LAWeekly, April 4-10. [5] A. Saleh (2001), Capturing the Earth's songs. ABC Science Online. Fore more details the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer.
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Dark nuclear strings as analogs of as analogs of DNA-, RNA- and amino-acid sequences and baryonic realization of genetic code
In the earlier posting I considered the possibility that the evolution of genome might not be random but be controlled by magnetic body and that various DNA sequences might be tested in the virtual world made possible by the virtual counterparts of bio-molecules realized in terms of the homeopathic mechanism as it is understood in TGD framework. The minimal option is that virtual DNA sequences have flux tube connections to the lipids of the cell membrane so that their quality as hardware of tqc can be tested but that there is no virtual variant of transcription and translation machinery. One can however ask whether also virtual amino-acids could be present and whether this could provide deeper insights to the genetic code.
The minimal option is that virtual DNA sequences have flux tube connections to the lipids of the cell membrane so that their quality as hardware of tqc can be tested but that there is no virtual variant of transcription and translation machinery. One can however ask whether also virtual amino-acids could be present and whether this could provide deeper insights to the genetic code.
The following model indeed reproduces the genetic code directly from a model of dark neutral baryons as strings of 3 quarks connected by color flux tubes.
1. States in the quark degrees of freedom Consider first the states of dark baryons in quark degrees of freedom. These states can be constructed as representations of rotation group and strong isospin group.
2. States in the flux tube degrees of freedom Consider next the states in flux tube degrees of freedom.
3. Analogs of DNA,RNA, aminoacids, and of translation and transcription mechanisms Consider next the identification of analogs of DNA, RNA and aminoacids and the baryonic realization of the genetic code, translation and transcription.
4. Understanding the symmetries of the code Quantum entanglement between quarks and color flux tubes would be essential for the baryonic realization of the genetic code whereas chemical realization could be said to be classical. Quantal aspect means that one cannot decompose to codon to letters anymore. This raises questions concerning the symmetries of the code.
Natural candidates for the building blocks of the analogs of these symmetries are the change of the sign of the spin direction for quarks and for flux tubes.
5. Some comments about the physics behind the code Consider next some particle physicist's objections against this picture.
The conclusion is that genetic code can be understand as a map of stringy baryonic states induced by the projection of all states with same spin projection to a representative state with the same spin projection. Genetic code would be realized at the level of dark nuclear physics and perhaps also at the level of ordinary nuclear physics and that biochemical representation would be only one particular higher level representation of the code. A hierarchy of dark baryon realizations corresponding to p-adic and dark matter hierarchies can be considered. Translation and transcription machinery would be realized by flux tubes connecting only states with same quark spin and flux tube spin. Charge neutrality is essential for having only the analogs of DNA, RNA and aminoacids and would guarantee the em stability of the states. For details see the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer.
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Could virtual DNAs allow a controlled development of the genome?
In the previous postings I have discussed TGD based model of homeopathy and phantom DNA based on the possibility that water molecules receiving the magnetic bodies of biomolecules in homeopathic manifacture process can mimick those aspects of these molecules most relevant for the biological functions. By combining these ideas with DNA as topological quantum computer hypothesis, one ends up with the idea that the evolution of DNA is not just random mutations plus selection, but takes place in controlled manner like the development of computer hardware in the virtual mimicry of internal chemical milieu in turn providing an abstract representation for the external world. The fundamental question in the evolution biology is the question about the interaction between genome (G), phenotype (P), and environment (E).
In TGD framework the sequence G® P-E is replaced with a closed loop G-P-M-E to which E is attached at P by bidirectional arrow (organisms do also modify their environment actively). Magnetic body thus controls genome and receives information from cell membrane (P). The hierarchy of genomes (super-genome, hyper-genome,...) corresponding to the different levels of dark matter hierarchy allows this loop to be realized in different scales rather only at the level of single cell. The question is whether the magnetic body of organism or higher level magnetic bodies could modify genomes, super-genomes, and hyper-genomes directly, perhaps by generating mutations of the genome in a short time scale; by monitoring how genetically modified organism survives in the environment; and -if the outcome of the experiment is successful - replacing the corresponding portion of DNA with the modified DNA both in ordinary germ cells. One can even ask whether the abstract model of the external environment provided by the internal chemical milieu might be mimicked by water magnetic bodies of water molecule clusters and provide a virtual world testing ground for a search of favorable mutations. In DNA as a tqc vision essentially the development of a new computer hardware would be in question, and should take place in a controlled manner and involve an experimentation before going to the market rather than by random modifications taking place in computer CPUs. Second basic aspect of DNA as tqc paradigm is that water and bio-molecules live in symbiosis in the sense that self organization patterns of the cellular water flow define the tqc programs. The following first guess for how the development of computer hardware might be achieved is just a first guess but might have something to do with reality.
For details see the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer.
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A possible realization of water memory
The Benveniste's discovery of water memory initiated quite dramatic sequence of events. The original experiment involved the homeopathic treatment of water by human antigene. This meant dilution of the water solution of antigene so that the concentration of antigene became extremely low. In accordance with homeopathic teachings human basophils reacted on this solution. The discovery was published in Nature and due to the strong polemic raised by the publication of the article, it was decided to test the experimental arrangement. The experimental results were reproduced under the original conditions. Then it was discovered that experimenters knew which bottles contained the treated water. The modified experiment in which experimenters did not possess this information failed to reproduce the results and the conclusion was regarded as obvious and Benveniste lost his laboratory among other things. Obviously any model of the effect taking it as a real effect rather than an astonishingly simplistic attempt of top scientists to cheat should explain also this finding. The model based on the notion of field body and general mechanism of long term memory allows to explain both the memory of water and why it failed under the conditions described. 1. A model for the water memory and homeopathic effect
2. Why Benveniste's experiments could not be replicated? Consider now the argument explaining the failure to replicate the experiments of Benveniste.
For details see the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer.
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Phantom DNA effect
Phantom DNA is fourth anomalous effect in which the notion of magnetic body provides understanding (other three effects have been discussed in three previous postings). In phantom DNA effect [1] there is an elastic scattering of the coherent laser radiation from irradiated DNA. When one removes the DNA from the chamber containing it, and irradiates it by laser light, a weak pattern of scattered light is still produced: as if there were a kind of phantom DNA there. The pattern can last for months. For years ago I considered an explanation of the effect based on dropping of part of DNA to larger space-time sheets characterized by larger value of p-adic prime and remaining in the vessel as visible DNA is removed . A variant of this explanation inspired by the dark matter hierarchy is that the anomalous scattering takes place on dark DNA at wormhole flux tubes remaining in the vessel. The DNA strands would simply lose their magnetic bodies which could be stealed by clusters of water molecules so that they become able to mimic DNA molecules as far as their magnetic bodies are considered. The most science fictive possibility is that the flux tubes connect the vessel boundaries to the removed DNA by wormhole flux tubes which are very long and correspond to a large value of hbar. In this case the scattering would involve a phase transition increasing the value of Planck constant and a travel of photons to the removed DNA and back followed by a phase transition to ordinary photons. Similar explanation works also in the case of homeopathy and allows to understand why the classic experiments of Benveniste could not be replicated when experimenters did not know which bottles contained the treated water. In this case the molecules dissolved in water would lose their magnetic bodies as a consequence of the shaking of the homeopathic remedy and one can say that clusters of water molecules would steal their magnetic coats. This would allow them to mimic the behavior of molecules and their presence would allow the immune system would develop a resistance against real molecules. This of course works only if the cyclotron radiation from the magnetic body is responsible for the biological effects. It is known that em radiation at low frequencies is indeed responsible for the ability of molecules to recognize each other. The generation of cyclotron radiation requires metabolic energy and the magnetic flux tubes connecting the experimenter to the treated bottle of water (correlates for directed attention) could have served as bridges along which metabolic energy could be transferred by using topological light rays (MEs serving as TGD counterparts of Alfwen waves). Experimentalists certainly did have strong desire to have successful experiments and this helped to realize the transfer of the metabolic energy. If this is the correct explanation of phantom DNA effect and homeopathy, homeopathy and phantom DNA effect would provide fundamental research tools for studying the physics of the magnetic bodies of bio-molecules. Since dark matter characterized by large values of Planck constants is expected to reside at the magnetic bodies, also the study of dark matter would become possible using these methods. For details see the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer of "Genes and Memes".
References [1] P. P. Gariaev, V. I. Chudin, G. G. Komissarov, A. A. Berezin , A. A. Vasiliev (1991), Holographic Associative Memory of Biological Systems}, Proceedings SPIE - The International Society for Optical Engineering. Optical Memory and Neural Networks. v.1621, p. 280- 291. USA. |
Has dark matter at the magnetic flux tubes been photographed?I spent a very pleasant week in Hungary in second Unified Theories conference (thanks for organizers for creating extremely warm atmosphere) and had the opportunity to listen Peter Gariaev's lecture about the fascinating experimental discoveries made by his group about the interaction of laser light and also ordinary light with DNA. The lecture and the discussions with Peter led to an updating of eight-year old model for these effects and summarized the updated model in the article that I titled The Notion of Wave-Genome and DNA as Topological Quantum Computer. I glue below the introduction of the article. The Notion of Wave-Genome and DNA as Topological Quantum ComputerFor about eight years ago - inspired by a representation in CASYS¢2000 conference [1] - I developed a model (see this) for the fascinating effects of laser light on genome discovered by Peter Gariaev and his collaborators [1,2,3,4,5]. This model is somewhat obsolete since it does not involve the recent TGD inspired vision about quantum biology and DNA, and the discussions with Peter in the second Unified Theories conference 2008 in Budapest made clear the need to update this model containing also some misinterpretations. In this article the effects of laser light on living matter are discussed only briefly with a stronger emphasis on the photographs produced by the scattering of ordinary light on DNA reported in [5]. In TGD framework these photographs could be interpreted as photographs of wormhole magnetic flux tubes containing dark matter. This would realize the dream of making directly visible the basic new structure predicted by TGD inspired quantum biology. 1 The findings of Peter Gariaev and collaboratorsThese findings include the rotation of polarization plane of laser light by DNA [1], phantom DNA effect [4], the transformation of laser light to radiowave photons having biological effects [4], the coding of DNA sequences to the modulated polarization plane of laser light and the ability of this kind of light to induce gene expression in another organisms provided the modulated polarization pattern corresponds to an "address" characterizing the organism [1,4], and the formation of images of what is believed to be DNA sample itself and of the objects of environment by DNA sample in a cell irradiated by ordinary light in UV-IR range [5]. Gariaev and collaborators have introduced the notion of wave genome [1] requiring the coding of DNA sequences to temporal patterns of coherent em fields forming a bio-hologram representing geometric information about the organism. Code could mean that nucleotide is represented by a characteristic rotation angle for the polarization plane of linearly polarized laser radiation scattering from it. This kind rotation is known to be induced by chromosomes by a mechanism which to my best knowledge is poorly understood. Other open questions concern the precise identification of the substrate of the bio-hologram, of the reference wave and of information carrying wave, and of the mechanism making possible (quantum) coherence in macroscopic length scales. The reading of the DNA sequence to a radiation pattern is assumed to rely on the propagation of an acoustic soliton along DNA [1]. Whatever this process is, one should also identify the reverse process inducing the activation of the genome as the target organism receives the radiation coding for the DNA provided the "address" is correct. One should also identify the mechanism transforming laser radiation to radio-waves at various frequencies as well as the mechanism creating what is believed to be the image of DNA sample and replicated images of some instruments used in experiment.2 The relevant aspects of TGD based view about living matterThe called massless extremals (MEs or topological light rays) distinguish between TGD and Maxwell's electrodynamics: they represent classically signals propagating with light velocity in a precisely targeted and dispersion free manner, and are therefore excellent candidates for the communication and control tools in the TGD based model for a living system as a conscious hologram (see this) and this). The notion of magnetic/field body, which can have layers of even astrophysical size, is an essential element of the model. Magnetic body uses biological body as a sensory receptor and motor instrument and MEs mediate sensory input and control signals between the two kinds of bodies (see this). I have already earlier applied MEs and the notion of magnetic body in an attempt to understand Gariaev's findings (this). The new element is the model for DNA as topological quantum computer (tqc) (see this) based on time-like braidings of so called wormhole magnetic flux tubes connecting nucleotides to the lipids at lipid layers nuclear and cell membranes. The model leads to a wide variety of predictions about DNA itself (see this), to a universal model for a tissue memory in terms of space-like braidings of wormhole magnetic flux tubes (see this), to a more detailed model of nerve pulse explaining also the origin of EEG and its synchrony (this), to a model for the evolution of the genetic code (see this), to a model of catalyst action involving a phase transition reducing the value of Planck constant inducing the shortening of the flux tubes connecting the reacting molecules and thus forcing them to the vicinity of each other, and to a model of for protein folding (this) in which the presence of wormhole magnetic flux tubes connecting bio-molecules becomes almost a definition for what it is to be living. It is interesting to combine these new ideas with the earlier [1,2,2,4] and more recent [5] findings of Gariaev. Basically the challenge is to fuse the DNA as tqc model with the model of living systems as a conscious hologram (see this).3 The basic assumptions of model explaining findings of GariaevThe basic assumptions of the model to be discussed are following.
References[1] P. Gariaev et al (2000), The DNA-wave-biocomputer, CASYS'2000, Fourth International Conference on Computing Anticipatory Systems, Liege, 2000. Abstract Book, Ed. M. Dubois. [2] P. Gariaev, Brief introduction into WaveGenetics. Its scope and opporturnities., http://www.wavegenetics.jino-net.ru. [3] P. P. Gariaev et al(2002), The spectroscopy of bio-photons in non-local genetic regulation, Journal of Non-Locality and Remote Mental Interactions, Vol 1, Nr 3.http://www.emergentmind.org/gariaevI3.htm . [4] P. P. Gariaev, V. I. Chudin, G. G. Komissarov, A. A. Berezin , A. A. Vasiliev (1991), Holographic Associative Memory of Biological Systems, Proceedings SPIE - The International Society for Optical Engineering. Optical Memory and Neural Networks. v.1621, p. 280- 291. USA. [5]P. P. Gariaev, G. G. Tertishni, A. V. Tovmash (2007), Experimental investigation in vitro of holographic mapping and holographic transposition of DNA in conjuction with the information pool encircling DNA, New Medical Tehcnologies, #9, pp. 42-53. The article is in Russian but Peter Gariaev kindly provided a translation of the article to English. [6] F. A. Popp, B. Ruth, W. Bahr, J. Böhm, P. Grass (1981), G. Grolig, M. Rattemeyer, H. G. Schmidt and P. Wulle: Emission of Visible and Ultraviolet Radiation by Active Biological Systems. Collective Phenomena(Gordon and Breach), 3, 187-214. [7]Faraday effect, http://en.wikipedia.org/wiki/Faraday-effect. For more details see the chapter The Notion of Wave-Genome and DNA as Topological Quantum Computer. See also the article The Notion of Wave-Genome and DNA as Topological Quantum Computer. |
A Model for Protein Folding and Bio-catalysisThe model for the evolution of genetic code leads to the idea that the folding of proteins obeys a folding code inherited from the genetic code. After some trials one ends up with a general conceptualization of the situation with the identification of wormhole magnetic flux tubes as correlates of attention at molecular level so that a direct connection with TGD inspired theory of consciousness emerges at quantitative level. This allows a far reaching generalization of the DNA as topological quantum computer paradigm and makes it much more detailed. By their asymmetric character hydrogen bonds are excellent candidates for magnetic flux tubes serving as correlates of attention at molecular level. The constant part of free amino-acid containing O-H, O=, and NH2 would correspond to the codon XYZ in the sense that the flux tubes would carry the "color" representing the four nucleotides in terms of quark pairs. Color inheritance by flux tube reconnection makes this possible. For the amino-adics inside protein O= and N-H would correspond to YZ. Also flux tubes connecting the acceptor atoms of hydrogen bonds are required by the model of DNA as topological quantum computer. The long flux tubes between O= atoms and their length reduction in a phase transition reducing Planck constant could be essential in protein-ligand interaction. The model predicts a code for protein folding: depending on whether also =O-O= flux tubes are allowed or not, Y=Z or Y=Zc condition is satisfied by the amino-acids having N-H-O= hydrogen bond. For =O-O= bonds Y-Yc pairing holds true. Y=Zc option predicts the average length of alpha bonds correctly. Y=Z rule is favored by the study of alpha helices for four enzymes: the possible average length of alpha helix is considerably longer than the average length of alpha helix if gene is the unique gene allowing to satisfy Y=Z rule. The explicit study of alpha helices for four enzymes demonstrates that the failure to satisfy the condition for the existence of hydrogen bond fails rarely and at most for two amino-acids (for 2 amino-acids in single case only). For beta sheets there ar no failures for Y=Z option. The information apparently lost in the many-to-one character of the codon-amino-acid correspondence would code for the folding of the protein and similar amino-acid sequences could give rise to different foldings. Also catalyst action would reduce to effective base pairing and one can speak about catalyst code. The DNA sequences associated with alpha helices and beta sheets are completely predictable unless one assumes a quantum counterpart of wobble base pairing meaning that N-H flux tubes are before hydrogen bonding in quantum superpositions of braid colors associated with the third nucleotides Z of codons XYZ coding for amino-acid. Only the latter option works. The outcome is very simple quantitative model for folding and catalyst action based on minimization of energy and predicting as its solutions alpha helices and beta sheets. I want to express my gratitude for Dale Trenary for interesting discussions, for suggesting proteins which could allow to test the model, as well as providing concrete help in loading data help from protein data bank. Also I want to thank Timo Immonen for loaning the excellent book "Proteins: Structures and Molecular Properties" of Creighton. Also Pekka Rapinoja for writing the program transforming protein data file to a form readable by MATLAB.For details see the new chapter A Model for Protein Folding and Bio-catalysis.
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TGD based model for the evolution of genetic code: VIFirst some context. I have discussed the model for the evolution of genetic code and the ideas inspired by this model in previous postings (I, II, III, IV,V). The model for the evolution of genetic code leads to the idea that the folding of proteins obeys a code inherited from genetic code in the sense that aminoacid behaves like the conjugate Yc of the middle nucleotide of the codon XYZ coding for it and that flux tubes connecting aminoacids to each other connect conjugate aminoacids behaving like Y and Yc. Also catalyst action would reduce to effective base pairing in this picture. After some trials one ends up with a general conceptualization of the situation with the identification of wormhole magnetic flux tubes as correlates for attention at molecular level so that a direct connection with TGD inspired theory of consciousness emerges at quantitative level. This allows a far reaching generalization of the DNA as topological quantum computer paradigm and makes it much more detailed. Also earlier vision about function of neurotransmitters and other information molecules as carriers of links in the web formed by living body becomes very concrete. The final outcome is very simple quantitative model for folding and catalyst action based on minimization of energy and consistent with basic experimental facts as well as general ideas. Because the model represents a quantitative breakthrough in the evolution of the TGD based view about quantum biology and to save the time required by the painstaking manual tex-html translation, I decided to represent the material also as article entitled From Genetic Code to Code for Folding and Catalysis. The background making it easier to understand can be found in the chapter Evolution in Many-Sheeted Space-time containing also the article as a section.
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TGD based model for the evolution of genetic code: VFirst some context. I have discussed the model for the evolution of genetic code and the ideas inspired by this model in previous postings (I, II, III, IV). Biochemistry represents extremely complex and refined choreography. It is hard to believe that this reduces to a mere an unconscious and actually apparent fight for chemical survival. In TGD Universe consciousness would be involved even at the molecular level and magnetic body would be the choreographer whose dance would induce the molecular activities. This picture combined with the idea of standard plugs through and terminals at which flux tubes end, leads to a third trial to understand catalytic code. The third trial differs from the second trial in that the letters X,Y,Z of the codon XYZ coding for the aminoacid do not correspond to COOH, residy R, and NH2 group. Rather, free aminoacid behaves like XY as in the first trial and X and Y correspond to flux tubes ending at OH and =O in COOH group. For the new option all - not only alpha helical and beta sheeted - aminoacids in the interior of the aminoacid sequence behave like the conjugate of letter Y for the codon XYZ coding for the aminoacid. The new model predicts that DNA, mRNA, tRNA, and aminoacids are in general connected by braid strands and provides a detailed picture about the role of braidings in transcription and translation. The topological dynamics of the magnetic body, its motor activities, would induce catalytic dynamics. Also a far reaching generalization of DNA as tqc paradigm emerges (see the postings I, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII,XIII). 1. Flux tubes as a correlate for directed attention Molecular survival is the standard candidate for the fundamental variational principle motivating the molecular intentional actions. There is entire hierarchy of selves and the survival at the higher level of hierarchy would force co-operation and altruistic behavior at the lower levels. One might hope that this hypothesis reduces to Negentropy Maximization Principle, which states the information contents of conscious experience is maximized. If this picture is accepted, the evolution of molecular system is analogous to the evolution of a society. Directed attention is the basic aspect of consciousness and the natural guess would be that directed attention corresponds to the formation of magnetic flux tubes between subject and target. The directedness property requires some manner to order the subject and target.
Attention can be also redirected. For this process there is a very nice topological description as a reconnection of flux tubes. What happens is that flux tubes A→ B and C → D fuse for a moment and become flux tubes A→ D and C→ B. This process is possible only if the strands have same color so that the values of the quark charges associated with A and B are same. This kind of process can modify tqc programs. For instance, in the case of the flux tubes coming from nucleotides X and Xc and ending to the lipid layer this process means that X and Xc and corresponding lipids become connected and genome builds memory representation about this process via similar link. If proteins are connected with mRNA connected to DNA in this manner, this process would allow the formation of flux tubes between aminoacids of two proteins in such a manner that protein would inherit from DNA codon the color of the middle nucleotide and its interactions effectively reduce to base pairing. DNA would have memory representation about molecular processes via these changing braiding topologies, and one could say that these molecular processes reflect the bodily motions of the magnetic body. Entire molecular dynamics of the organism could represent an enormous tqc induced by the motor activities of the magnetic body. At the level of sensory experience similar idea has been discussed earlier: Out of Body Experiences and illusions such as train illusion could be understood in terms of motor action of magnetic body inducing virtual sensory percepts. Attention can be also switched on and off. Here the structure of the lipid ends containing two nearby situated =O:s suggest the mechanism: the short flux tube connecting =O:s disappears. The minimization of Coulomb interaction energy at each end implies that re-appearance of the flux tubes creates a short flux tube with the original strand color. 2. Where do flux tubes begin from? The view about magnetic body as a controller of biological body using genome as a control tool suggests that DNA is to a high degree responsible for directed attention and other molecules as targets so that flux tubes emanate from DNA nucleotides. The reason would be that the aromatic cycles of DNA correspond to larger value of Planck constant. Some chemical or geometric property of DNA nucleotides or of DNA nucleotides of DNA strand could raise them to the role of subject. Aromatic cycle property correlates with the symmetries associated with large value of Planck constant and is the best candidate for this property. If this is accepted then also some aminoacid residues might act as subjects. Phe, His, Trp, Tyr contain aromatic cycle. The derivatives of Trp and Tyr act as neurotransmitters and His is extremely effective nucleophilic catalyst. This would make possible more specific catalytic mechanisms through the pairing of Phe, His, Trp, and Tyr with residues having flux tube terminals. This raises the question about the physical interaction determining the color of the strand emerging from the aromatic cycle. The interaction energy of quark at the end of flux tube with the classical electromagnetic fields of nuclei and electrons of the ring should determine this. The wormhole contact containing quark/antiquark at the throat at space-time sheet containing nuclei and electrons could also delocalize inside the ring. One of the earliest hypothesis of TGD inspired model for living matter was that wormhole Bose-Einstein condensates could be crucial for understanding of the behavior of biomolecules. Wormhole throats with quark and antiquark at their throats appear also in the model of high Tc superconductivity. The only manner for the electronic space-time sheet to feed its electromagnetic gauge flux to larger space-time sheets using exactly two wormhole contacts is to use wormhole contacts with uc and d at their "upper" throat (T,G). For proton one would have dc and u at their "upper" throat (A,C). The presence of electron or proton at nucleotide space-time sheet near the end of flux tube might allow to understand the correlation. The transfer of electrons and protons between space-time sheets with different p-adic length scale is basic element of TGD based model of metabolism so that there might be some relation. 3. What aminoacids can act as plugs and terminals of flux tubes? Standardization constraint suggests that flux tubes are attached to standard plugs and terminals. The explicit study of various biological molecules and the role of water in biology suggests that =O serves as a plug to which flux arrives and from which it continues. The intuitive reason for the proposal is that =O allows two hydrogen bonds. OH would in turn correspond to a terminal at which flux tube ends. One might be very naive and say that conscious biomolecules have learned the fundamental role of oxygen and water in the metabolism and become very attentive to the presence of =O and OH. =O appears in the residues of Asp, Glu, Asn, Gln. OH groups appear inside the residues of Asp,Glu and Ser, Thr. It might not be very wise to restrict the molecular attention to only =O and OH and it is probably better to speak about probabilities for the flux tubes to attach to various kinds of terminals. Both SH and NH2 are chemically like OH both these them could act as terminals of flux tubes: NH2 (Asp,Gly,Glu,Arg) contain NH2 and Cys contains SH.
4. Directed attention generates memory representations and tqc like processes Directed attention induces braiding if the target is moving and changing its shape. This gives rise to a memory representation of the behavior of the object of attention and also to a tqc like process. A considerable generalization of tqc paradigm suggests itself. Tqc could be induced by the braiding between DNA and lipids, DNA and proteins via folding processes, DNA RNA braiding and braiding between DNA and its conjugate, DNA and protein braiding. The outcome of tqc would be represented as the temporal patterns of biochemical concentrations and rates and there would be hierarchy of p-adic time scales and those associated with the dark matter hierarchy. For instance, the protein content of lipid membranes is about 50 per cent and varies between 25 and 75 per cent so that protein folding and lipid flow could define tqc programs as self-organization patterns. The folding of protein is dynamical process: alpha helices are created and disappear in time scale of 10-7 seconds and the side chains of protein can rotate. The details of the tqc like process depend on what one assumes. The minimal scenario is deduced from the transcription and translation processes and from the condition that magnetic body keeps control or at least keeps book about what happens using genome as a tool. The picture would be essentially what one might obtain by applying a rough model for web in terms of nodes and links.
4. Introns and DNA-protein attachment An example is the situation in which protein acts as an enzyme attaching on DNA. Suppose that this process effectively reduces to a base pairing between aminoacid and DNA nucleotide. Protein can attach to any portion of DNA. Since nucleotide triplets and aminoacids in the first approximation correspond to same length in the respective chains, amino-acid is expected to correspond to nucleotide triplet. The simplest interaction is the attachment to the gene coding for the aminoacid itself but much more general enzymatic interactions are possible. This works if the gene does not contain introns or if the attachment is along single exon. It is known that DNA can change its conformation from strand during enzyme-DNA action and the contraction of DNA strand might make possible to have enzyme-DNA interaction also in the case that attachment region corresponds to several exons. One can of course ask whether genes containing introns tend to code for proteins which are used for topological quantum computations. Introns, perhaps the repeating sequences with no obvious function, would have at least this useful function but very probably much more useful ones too (they are now known to be transcribed to RNA and TGD suggest that language corresponds to intronic gene expression). The emergence of introns might be somewhat like the emergence of information society. The foldings of proteins tend to be conserved in the evolution whereas primary structure can change quite a lot apart from some aminoacids critical for enzymatic action. This confirms with the effective base pairing interaction between aminoacids and DNA and would mean that DNA-aminoacid tqc programs are rather robust against mutations. 5. Evolution and braidings The evolution at the molecular level corresponds to the emergence of increasingly complex molecules using as basic building blocks aminoacid chains and non-translated residues attached to them in the post-translational processing of the aminoacid chains. Also increasingly complex reaction paths emerge. Molecular survival and the competition for the metabolic resources at molecular level could be seen as the basic driving force of this evolution. Typically, in the original situation the enzymes would have received the substrate molecules from the environment but sooner or later this would have become difficult. The solution would have been a synthesis of the substrate from simpler ingredients by starting from some precursor. If molecules (with magnetic bodies included) are conscious entities able to direct attention, one can imagine that magnetic body controlling them with the mediation of genome and able to actively modify it, could help through modifications of the genome to create to the catalyst a binding site able to bind the precursor. Immune system is doing this very intensively. If the enzyme binding the precursor already exists, a combination of genes coding for the enzyme and the enzyme having the metabolites as ligands could allow to achieve this. All this would reduce to the motor activities of magnetic body, in particular reconnection of flux tubes, kind of Shivas dance. Genome would not be anymore a sequence of DNA developing through random mutations under selection pressures. Can one make any clear cut predictions about preferred mutations?
In this framework aminoacids would have appeared before their precursors and possessed some function in RNA world, say the catalysis of join of RNA2 dinucleotides to the increasing chain as I have proposed. Competition might have led to the situation in which RNA2 learned to catalyze selectively generation of aminoacids from much simpler precursors (three of the proposed precursors contain only C,=O, and O-). The reduced genetic code would have been present at two levels: reader can decide whether this is a shortcoming of the model or a fundamental biochemical duality implying an exponential amplification of RNA and aminoacid populations. For details see the chapter A Evolution in Many-Sheeted Space-time.
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TGD based model for the evolution of genetic code: IVI have discussed the model for the evolution of genetic code in previous postings (I,II,III). Thanks to the Ulla Mattfolk I learned about the idea of protein folding code - something which is expected to exist but is not understood. This led to a trial for the folding code discussed in posting III) and based on the assumption that aminoacid behaves like dinucleotide. This trial did not work but the learning of some basic facts about proteins and their interactions inspired second trial according to which aminoacid in the interior of aminoacid sequences behave like the conjugate of the nucleotide Y of the codon XYZ coding for it. This trial seems to work. There exists a wonderful book "Proteins: Structures and Molecular Properties" by Thomas E. Creighton and published 1993 by W. H Freeman Company. In the following I freely refer to the general facts discussed in this book rather than referring separately to every detail. While reading this book I learned that the first guess for the code of catalysis was wrong but is also became clear what was wrong. It became clear that free aminoacid should behave like the conjugate of the DNA codon XYZ -rather than only XY- but that an aminoacid inside aminoacid sequence effectively reduces to Y since the formation of the peptide bonds by the elimination of water molecule and formation of NH---O= hydrogen bonds effectively eliminates X and Z. The ends of aminoacid behave like dicodons which conforms with their special role in biocatalysis. Only aminoacids for which Y corresponds to quarks (not antiquarks) can form hydrogen bonds so that hydrophilic-hydrophobic dichotomy corresponds to a strong matter antimatter asymmetry at quark level. 1. Matter antimatter asymmetry at the level of interactions of aminoacids The first thing that I learned was that second nucleotide Y in the codon XYZ coding for aminoacid is what matters. Only Y=A,G aminoacid residue can form hydrogen bonds and is hydrophilic and thus interacts strongly with water and DNA and RNA. In T,C case the formation of hydrogen bonds is impossible or rare (ser,thr). In their interactions with water these aminoacids are passive, or rather-avoid water- and tend to interact with each other. This division is fundamental for the understanding of the interactions of aminoacids. The division of aminoacids to hydrophobic resp. non-hydrophobic ones corresponds to the assignment of quarks to A and G and antiquarks to T and C so that strong matter antimatter asymmetry is in question. Similar asymmetry appears in cosmology: in TGD Universe antimatter resides inside cosmic strings in the interior of big voids containing matter as galaxies at their boundaries so that one can understand why antimatter is not visible. 2. Flux tubes can connect with all electronegative atoms Also a plausible answer to the question which atoms can be connected by flux tubes emerges.
3. What can one learn from the formation of alpha helices and beta sheets? The formation of peptide bonds by the elimination of H2O= molecules and generation of hydrogen bonds between NH and O= is an essential step in the formation of alpha helices and beta sheets. Second observation is that aminoacids decompose naturally into three parts corresponding to O=COH, R, and NH2. This suggests that aminoacid actually corresponds to the entire DNA codon XYZ coding for it. OH could correspond to Z , R to Y, and NH2 to Z. In the formation of peptide bond the flux tube connecting to COH and thus to Z would be taken by the water molecule created in the formation of peptide bond leaving only XY. The first flux tube would connect HN and O= so that X would pair with Xc assignable to O. There are no problems with the formation of bond if O= can correspond to any code letter as in the case of water. Water would correspond to matter antimatter symmetric phase and an interesting question is what counterpart this phase could have in cosmology (bosonic matter?). The aminoacid inside protein would effectively behave like Yc in the effective base pairing. Depending on whether it corresponds to quark or antiquark, aminoacid would be hydrophilic or hydrophobic- or rather - able to form hydrogen bonds or not. Since hydrophobic aminoacids cannot form hydrogen bonds, the formation of these residue pairs would be inhibited. The hydrophilic and hydrophobic residues could tend to avoid each other and the phase transitions increasing Planck constant would make this possible. It must be emphasized that this brings in strong long range correlation between the dynamics of the aminoacid residues belonging to the first and third (second and fourth) column of the code table. Hydrophilic aminoacids would form hydrogen bonds which each other and with DNA and RNA. In catalytic biding sites this kind of hydrogen bonds are formed between polar groups: also hydrogen bonds with water are formed and they tend to neutralize possible static charges. Ser (UCZ) and thr (ACZ) are the only effectively hydrophobic aminoacids containing OH group (and thus strictly speaking amphiphilic). Perhaps it is not an accident thr the codon ACC coding for thr appears in the stem of tRNA containing aminoacid. Ser and thr are indeed able to form hydrogen bonds with hydrophilic aminoacids and the prediction is that these aminoacids have form XGZ belonging to the last column of the code table. There are however very few biochemical reactions of this kind useful for proteins. Ser is exceptional in that it is predicted to be able to form flux tubes connecting ser_1 coded by TCZ with ser2 coded by AGZ, Z=T,C. The OH group of ser can be seen as a correlate for this property. The aminoacids at the ends of the polymer behave effectively like dinucleotides. The aminoacid coded by XYZ would base pair like XcYc if in the beginning of polymer and to YcZc if at the end of polymer. These nucleotides should have very special selective role in DNA-aminoacid and RNA-aminoacid interactions. Remarkably, it is known that the cutting of COOH and NH2 away from the end of polymer in general makes protein folding impossible (also mutations can affect dramatically folding). The first nucleotide of protein is usually met containing sulphur and the conjugation associates met with stop and tyr codons. The association of met with stop is indeed natural for the free NH2 of met having no hydrogen bond in the beginning of the sequence. According to Creighton, the binding sites of catalyst and ligand in the reaction complex are conjugates both geometrically and physically. It would be nice to have a concrete representation of this conjugacy in terms of the genetic code. Geometric conjugacy is easy to understand in terms of the lock and key picture but I am not quite sure what physical conjugacy could mean. Standard physics intuition would suggests that hydrophilic aminoacids that behave as acids resp. bases attract each other. This option does not possess any obvious formulation in the proposed picture. Matter antimatter conjugation for the second nucleotide Y of XYZ looks however very natural so that the aminoacids in the first and third (second and fourth) row of the code table would tend to pair with each other. This mechanism might be flexible enough to allow to find a conjugate of a given binding site by trial and error. The interpretation would be that hydrophobia tends to create concave and hydrophily convex structures. The attraction between Y and Yc in the braided conjugate regions would due to the Coulomb interaction between quark and antiquark at the ends of the wormhole flux tube. The strong correlation between RNA dinucleotide and aminoacid in the case of tRNA conforms with this picture. The third flux tube associated with the aminoacid could connect with the third codon after the transition to RNA-aminoacid era. During RNA era tRNA2 would have connected the O=C-OH part of the aminoacid to water molecule. 4. Interactions with DNA Also in the interactions with DNA and RNA the aminoacid in the interior of the sequence would base-pair" like Yc. The original idea about molecular sex would transform in the sense that the companion of the hydrophilic aminoacid would DNA nucleotide in general. Hydrophobic aminoacids would behave like hermits. The generic contacts with DNA would be contacts with single nucleotide and there would be 4 different basic contacts. Aminoacids are indeed known to form contacts with single nucleotide. Hydrophilic contacts would be favored and hydrophobic contacts avoided so that again Y=A,G aminoacids would play at the outer boundary of DNA would play the active role. The aminoacids inside a given column of the code table would interact in very much the same manner with DNA nucleotides as far as formation of hydrogen bonds is considered. The terminals of the protein polymer are predicted to behave like XcYc resp. YcZc if the corresponding codon is XYZ. Again only hydrophilic codons are expected to be able to form hydrogen bonds. N-terminal is usually met and met and should avoid DNA.
5. Interactions of proteins with ions and electrons Proteins interact also with electrons and ions. Typical process are the addition or removal of proton, electron, ion such Ca++, or molecule such as O2. These interactions are not well understood. For instance, the interactions involve the transfer of electrons between ligand protein and protein inducing oxidation (electron is given), reduction (electron is received) or redox reaction (both reduction and oxidation take place). In metabolism redox process is central. These reactions are reversible and it is difficult to understand how electrons are able make their long journey from the interior of the ligand so fast and avoiding dissipative effects. The formation of cyclotron Bose-Einstein condensates and electronic Cooper pair condensates at the magnetic flux tubes connecting ligand and protein could be the solution of the mystery.
6. How DNA nucleotides are connected with the hydrophilic ends of lipids? The starting point of all these developments was the model for DNA as topological quantum computer (tqc) described in the earlier postings I, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII, XIII. It was assumed that braid strands defined by "wormhole magnetic" flux tubes join nucleotides to lipids and can continue through the nuclear or cell membrane but are split during tqc. The hydrophilic ends of lipids attach to water molecules and self-organization patterns for the water flow in gel phase induce a 2-D flow in the lipid layer which is liquid crystal defining tqc programs at the classical level as braidings. The flow indeed induces braiding if one assumes that during topological computation the connection through the cell membrane is split and reconnected after the halting of tqc. The challenge is to understand microscopically how the flux tube joins DNA nucleotide to the phospholipid. What is clear that the points at which the flux tubes attach should be completely standard plugs and the mechanism giving rise to polypeptids is an excellent guide line here. Recall that phospholipid, the dancer, has two hydrophobic legs and head. Each leg has at the hydrophilic end O=C-O-C part joining it to glyceride connected to monophosphate group in turn connected to the hydrophilic residue R. The most often appearing residues are serine, inositol, ethanolamine, and choline. Only three of these appear in large quantities and there is asymmetry between cell exterior and interior. Let us denote by =O1 and =O2 the two oxygens in question (analogs of right and left hemispheres!). The proposal is that DNA nucleotide and =O1 are connected by a flux tube: the asymmetry between right and left lipid legs should determine which of the legs is "left leg" and which O= is the "left brain hemisphere". =O2, the holistic "right brain hemisphere", connects in turn to the flux tube coming from the other symmetrically situated =O2 at the outer surface of the second lipid layer. During tqc this flux tube is split or disappears. The lipid residue R couples with the flow of the liquid in gel phase. Since =O is in question the quark or antiquark at the end can correspond to the DNA nucleotide in question. Also the necessary complete correlation between quarks and antiquark charges at the ends of flux tubes associated with =O1 and =O2 can be understood as being due to the minimization of Coulomb interaction energy. The phosphate groups associated with nucleotides of DNA strand contain also =O, which could act as a plug to which the flux tube from the nucleotide is attached. =O appears in biomolecules involved with varying functions such as signalling, control, and metabolism. =O might act as a universal plug to which flux tubes from electronegative atoms of information molecules can attach their flux tubes. This would also provide a concrete realization of the idea that information molecules (neurotransmitters, hormones) are analogous to links in Internet (see this): they would not represent the information but establish a communication channel. The magnetic flux tube associated with the information molecule would connect it to another cell and by the join to =O plug having flux tube to another cell, say to its nucleus, would create a communication or control channel. To repeat the earlier statement, this proposal for the folding code - or rather, the code of entire biocatalysis - is so beautiful that it deserves to be killed: this should be easy for a professional biochemist. If the hypothesis survives, it would provide a royal road to the understanding of the catalytic bio-chemistry. For details see the chapter Evolution in Many-Sheeted Space-time.
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TGD based model for the evolution of genetic code: IIIUlla Mattfolk sent me again an interesting link, which happened to relate directly to what I have been doing during the last week, that is application of DNA as topological quantum computer hypothesis to the understanding of the evolution of the genetic code. The link was to an article about the idea of protein folding code - something which is expected to exist but is not understood. See also this. I realized that the prebiotic 2-code assigning to RNA dinucleotides aminoacids might define the folding code. This code would specify also what kind of catalytic reactions can occur between proteins and would dictate the catalytic stereo chemistry - or rather its changes - to a high degree.
Consider now objections against the proposal.
To sum up, this proposal for the folding code - or rather, the code of entire biocatalysis - is so beautiful that it deserves to be killed: this should be easy for a professional biochemist. If the hypothesis survives, it would provide a royal road to the understanding of the catalytic bio-chemistry. For details the chapter Evolution in Many-Sheeted Space-time.
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TGD based model for the evolution of genetic code: IIThe net is wonderful. Yesterday evening I decided to search for articles about the possible role of dinucleotides in prebiotic evolution. "Dinucleotide" as a search word gave something about NADH and the only thing I understood that this is not relevant. Then I decided to be very optimistic and use as search words "dinucleotide" "prebiotic" simultaneously. To my surprise I found two gems which guaranteed that I did not sleep too much during the last night! The first gem did not relate to dinucleotides in a direct manner but I learned that the attempts to synthesize RNA sequences from nucleotides lead to 2',5' form of RNA: recall that the production of 3',5' RNA sequences has not been successful, only single nucleotides have been produced (see the article Experimental Testing of Theories of an Early RNA World by A. D. Ellington). This fits completely with the cautious hypothesis that RNA1 indeed corresponds to 2',5' form of RNA consisting of A,G,U,I and that ordinary 3',5' RNA, which I call RNA2, emerged as dinucleotides, which can polymerize to longer sequences and that this process was catalyzed by aminoacids. Second gem was directly related to dinucleotides, prebiotics, and genetic code. Somewhat disappointingly, I am not the only person who has considered the idea of 2-code. The title of the paper by S.D. Copley. E. Smith and H. J. Morowitz was A mechanism for the association of aminoacids with their codons and the origin of the genetic code. To very briefly summarize the content of the paper (I am of course not chemist and I see the paper from by "biomolecules connected by magnetic flux tubes" perspective so that it is easy to ridicule me).
Consider now the interpretation of the results in TGD framework. The coding of the reaction pathway would be in terms of braid strands. The two ("wormhole") magnetic flux tubes beginning from the X and Y would end up to the precursor. The quark u,d or antiquark uc, dc labeling X would tell which precursor the magnetic flux tube ends at. What is the rule involved? What property of nucleotide X and precursor fixes the correspondence characterizing reaction pathway? It certainly seems that the flux tube connects X to a catalytic "hot spot" since X and this hot spot must end up near to each other in the phase transition reducing Planck constant and thus length of the magnetic flux tube. The charges possibly assignable with the hot spots - what ever they are - is a good guess but there is more involved. It seems that the nucleotides of codon are like 4-digits with first digits having the highest significance. The division of dinucleotide XY to two nucleotides should correspond to a similar division UV of the precursor to two parts. U would change in the reaction in the same manner for all aminoacids resulting from a given precursor but the change should depend on X. One can identify at U as a portion at the right end of the precursor (see the article). The left end of precursor would in turn connect with Y.
An ideal experimentalist with infinite brilliance and funding resources and enjoying endless trust of decision makers might be interested in carrying out the following experiments.
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TGD based model for the evolution of genetic code: IThe notion of many-sheeted space-time could allow to understand many puzzles related to the pre-biotic evolution (the popular article The Origin of Life on Earth, by Leslie Orgel gives a good overall view about the situation). There are many constraints on the models for pre-biotic evolution. The models have also many difficulties. In TGD framework the situation looks much better.
Q: Is life as we know it result of an accident? . A: Quantum TGD predicts a genuine cosmic evolution occurring by quantum jumps for which dynamics is characterized by Negentropy Maximization Principle. The generalization of the notion of space-time implies dark matter hierarchy with levels characterized by arbitrarily large values of Planck constant so that macroscopic quantum coherence is possible even in astrophysical length scales. Even astrophysical systems are analogous to atomic systems which implies a strong standardization of planetary system so that Earth like planets are abundant. There are also other good reasons for why the evolution of life would not have been accident in TGD Universe and life should appear everywhere in TGD Universe. Q: What were the most primitive living systems?
A: The notion of magnetic body brings to biology several completely new elements. Magnetic flux quanta containing dark charged matter and quantum controlling ordinary matter in plasma phase is perhaps the simplest system which can develop characteristics of a living system. The braiding of magnetic flux tubes makes possible topological quantum computation and a fundamental representation of memories and its presence could be even taken as a definition for what it is to be living. Tqc programs correspond to asymptotic self organization patterns for liquid flows inducing braidings and are non-trivial in presence of external energy feed. Q: How metabolic machinery emerged?
A: Many-sheeted space-time concept predicts a hierarchy of universal metabolic energy quanta as differences of zero point kinetic energies for space-time sheets characterized by different p-adic length scales. What remains is to understand how chemical energy storage and utilization mechanisms developed. Q: What is behind biocatalytic machinery?
A: The magnetic flux tubes connecting bio-molecules imply long range correlations between molecules. The reduction of Planck constant for magnetic flux tubes implying their shortening provides a mechanism making possible for bio-molecules to "find" each other in a very selective manner, and explains also why molecules end up to precisely defined conformations necessary for a selective bio-catalysis. This picture leads to amazingly detailed understanding of existing results about emergence of biomolecules in experimental arrangements modelling "primordial soup". Q: How symbolic dynamics emerged?
A: The notion of N-atom suggested by the fractionization of electron quantum numbers for dark matter hierarchy brings in a candidate for a symbolic dynamics assigning to molecules "names" which need not correlate very strongly with the chemical properties of the molecule but would dictate to a high degree its biochemical behavior. Molecular "sex" emerges in the sense that molecules labeled with "names" and "co-names" tend to pair. The model of DNA as tqc assumes a 4-coloring of braid strands realized by an assignment of DNA nucleotides to quarks and anti-quarks. Also this means symbolic dynamics since only molecules connected by colored braids have high probability to participate in same biochemical reaction and do it in a very specific manner. Since the quarks involved with braid strands can have fractional charges, molecular sex can be realized also in this manner. Q: What selected the bio-molecules during chemical evolution?
A: The proposed symbolic dynamics based on the notions of colored braids and N-atom poses very strong constraints on the subsets of bio-molecules that can react with considerable rates. The assignment of quark to nucleotides via the correspondence A,T,G,C→ u,uc,d,dc allows to basic rules about distribution of nucleotides in DNA and genes (differing from each other) and in mRNA in terms of approximate matter antimatter symmetry, isospin symmetry and the breaking of these symmetries. Matter antimatter asymmetry is visible also in the experiments trying to mimic primordial life. Q: How biochemical pathways emerged?
A: It is now possible to realize in practice sequences of arbitrarily complex self-catalyzing biochemical reactions utilizing DNA hairpins. The mechanism generalizes to more complex molecules. At a given step of the reaction sequence the structure formed during the previous steps acts as a key fitting to a lock represented by some hairpin in the solution, and opens it to a linear molecule and in this manner makes it a key. The braids between reactants make it possible for the key and lock to find each other. Q: How genetic code evolved?
A: The following gives a summary about what might have happened.
Q: Did RNA world precede the life as we know it?
A: The model for the evolution of the genetic code forces to conclude that RNA world preceded the recent biology and allows also to deduce that the nucleotides involved with second form of RNA where A,T,U,I(nositol). The exotic RNA in question could have been 2',5' form of RNA rather than 3',5' RNA but this is not the only possibility. Genetic code was implicitly present already during RNA era in the sense that aminoacids and RNA di-nucleotides were paired by braid strands (given aminoacid was connected to a dinucleotide defining the first two nucleotides of codons coding aminoacid). Hence the strong form of RNA world hypothesis would be wrong: aminoacids would have played a key role although their sequences would have been absent. Some examples are in order.
Q: Does the notion of protocell make sense?
A: The model of DNA as tqc involves essentially the magnetic flux tubes connecting DNA nucleotides and cell membrane. Since topological quantum computation should have taken place also during the RNA era, some kind of cell membrane consisting of exotic RNA should have been present. It has been found that DNA indeed forms membrane like structures which are liquid crystals consisting of sequences of DNA nucleotides with length up to 20 nucleotides (See this) and same might be true in the case of exotic RNA. Q: How life could evolve in the harsh primordial environment? Does the notion of primordial ocean make sense?
A: It seems plausible that primordial life came from interstellar space. Evolving life had however to cope with the grave difficulties due to the irradiation by UV light and meteoric bombardment. A simple solution of these problems is to evolve in the interior of Earth, say in underground lakes. This idea conforms nicely with the observation that continents would have formed a single super continent at time of Cambrian explosion provided the radius of Earth at that time was by a factor 1/2 smaller than now. TGD predicts that cosmic evolution does not occur continuously but by quantum jumps in which the Planck constant of appropriate space-time sheet increases. A phase transition of this kind increasing the radius of Earth during a relatively short time interval would have led to a burst of life from underground lakes to the surface of Earth. This would also explain the sudden emergence of a huge variety of highly developed life forms during Cambrian explosion. The answers to these questions give only a rough view about TGD based model of prebiotic evolution. A detailed picture (still developing) can be found from the completely rewritten chapter Evolution in Many-Sheeted Space-time. I have also re-organized the book completely to better reflect the progress due to the model of DNA as topological quantum computer.
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DNA as topological quantum computer: XIIIIn previous postings I, II, III, IV, V, VI, VII, VIII, IX, X, XI, XII I have discussed various aspects of the idea that DNA could acts as a topological quantum computer using fundamental braiding operation as a universal 2-gate. The model of DNA as topological quantum computer was originally motivated by the idea that quantum biology in TGD Universe might teach something about quantum computation like processes possibly taking place in living matter. It turned out that the model of DNA as topological quantum computer began to give lessons about quantum biology. In particular, one must assign 4-color to braid strands represented as flux tubes connecting DNA nucleotides A,T,C,G to lipids of nuclear or cellular membranes. In TGD Universe this color is naturally represented in terms 2 quarks u,d and their antiquarks (scaled up variants of ordinary quarks with large hbar and residing at flux tubes of "wormhole" magnetic fields defining the braid strands). This sounds definitely something very weird for anyone still inhabiting the simple standard model universe and not gone through 28 year lasting process of discovery starting from the basic idea of TGD and ending up with the recent highly refined picture about how TGD Universe differs from that of standard model. Recall however that the discovery of Barbara Shipman that the patterns of honeybee dance can be understood in terms of the mathematics of color group SU(3) of strong interactions, led her to suggest that quarks are directly involved with cognition and memory. This makes sense since DNA as tqc using 4-colored braids is expected to be closely involved with cognition and memory. The model led to the prediction that coding regions of DNA might be characterized by a breaking various symmetries at quark level, that is breaking of matter antimatter symmetry, isospin asymmetry, and asymmetry between uuc and ddc type matters (c refers to charge conjugation taking matter into antimatter) could take place at level of coding sequences. Three parameters should characterize this breaking. I made some sample calculations and found support for the breaking of matter antimatter and symmetry and the generation of anomalous em charge implied by this. Yesterday I learned (thanks go to Dale Trenary for crucial references) that simple basic facts about DNA which can be found from Wikipedia support the proposed vision about symmetry breaking although details were not quite correct.
It thus seems that DNA as tqc and the coding of braid color by quarks allows to understand the poorly understood empirical rules about the distribution of codons in DNA. Many fascinating questions and working hypothesis can be considered besides those proposed already earlier. For details see the chapter DNA as Topological Quantum Computer. See also the brief article here.
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DNA as topological quantum computer and ageingThe notion of anomalous em charge is one of the basic implications of the many-sheeted space-time concept. It can be assigned to wormhole contacts carrying fermion and antifermion quantum numbers at their throats. If the classical electromagnetic fields at the two space-time sheets are different, the wormhole contact couples to the difference of vector potentials and behaves like a particle with anomalous charge although the net charge is vanishing. In the model of DNA as topological quantum computer the braid strands (whose braiding defines tqc program) emanate from DNA nucleotides and end up to the lipids of the nuclear and cellular membranes. They are colored in the sense that one can tell whether the strand arrives from A,T,C or G. This is achieved by representing the braid strand as a wormhole magnetic flux tube with CP conjugate wormhole throats at its ends. To A,T,C,G one assigns a wormhole contact with quark u,d or its antiquark at the "upper" throat and its CP conjugate at the "lower" throat. There are also symmetries: A and T resp. G and C are mapped to quark and its antiquark so that DNA conjugation corresponds to CP conjugation. Chargaff's rules A≈ T and G≈ A for single DNA strand state that DNA as a whole is matter-antimatter symmetric. A and G are mapped to u,d or their antiquarks and correspond therefore to isospin doublet. This allows to interpret the almost exact A-G and T-C symmetries of the third nucleotide of codon in terms of strong isospin symmetry. Both symmetries can break down for short portions of DNA. The anomalous em charge of DNA is due to the fact that DNA is negatively charged (2 units of charge per nucleotide due to phosphate) and generates classical em field at the "upper" sheet of wormhole magnetic flux tube. The nearly vanishing Qa for DNA is interpreted as a stability condition for DNA. For long DNA strands Chargaff's rules A≈ T and G≈ A indeed guarantee the vanishing of Qa since A and T resp. C and G correspond to quark and its antiquark. There are four options concerning nucleotide quark correspondence and therefore also the identification of Qa: for one of them one has Qa= [2(A-T)-(G-C)]/3. Integer valuedness allows color singletness for the many quark-antiquark state assignable to DNA strand via the mapping of A,T,C,G to quarks and antiquarks. Telomeres are of special interests as far as anomalous em charge is considered. Chromosomes are not copied completely in cell replication, and one function of telomeres is to guarantee that the translated part of genome replicates completely for sufficiently many cell divisions. Telomeres consists of 3-20 kilobases long repetitions of TTAGGG, and there is a 100-300 kilobases long repeating sequence between telomere and the rest of the chromosome. Telomeres can form can also 4-stranded structures. Telemere end contains a hair-pin loop as a single stranded part, which prevents the action of DNA repair enzymes on the chromosome end. Telomerase is a reverse transcriptase enzyme involved with the synthesis of telomeres using RNA strand as a template but since its expression is repressed in many types of human cells, telomere length shortens in each cell replication. In the case of germ cells, stem cells and white blood cells telomerase is expressed and telomere length preserved. Telomere shortening is known to relate to ageing related diseases. On the other hand, overactive telomere expression seems to correlate with cancer. If telomeres possess braid strands, the compensation of Qa might provide an additional reason for their presence. If this the case and if telomeres are strict multiples of TTAGGG, the shortening of telomeres generates a non-vanishing Qa unless something happens for the active part of DNA too. Color singletness condition should however remain true: the disappearance of 3n multiples of TTAGGG in each replication is the simplest guess for what might happen. In any case, DNA strands would become unstable in cell replication. Qa could be reduced by a partial death of DNA in the sense that some portions of braiding disappear. Also this would induce ill functioning of tqc harware perhaps related to ageing related diseases. Perhaps evolution has purposefully developed this ageing mechanism since eternal life would stop evolution. For a more detailed exposition and background see the chapter DNA as Topological Quantum Computer.
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On direct testing of quantum consciousnessQuantum entanglement and its reduction in "cognitive" quantum measurement could provide a direct test of quantum consciousness. Andrei Khrennikov [1] has proposed a mathematical formulation of "quantum like" behavior based on his proposal that so called context dependent probabilities could provide alternative description for quantum mechanical interference phenomenon. In quantum theory context would correspond to the choice of quantization axis. Khrennikov has also proposed a modification of Bell inequalities so that they apply on conditional probabilities: this would make it possible to avoid the task of preparing entangled state of brains. The hope is that one could forget completely the microscopic structure of quantum brain and test quantum like behavior by making simple experiments involving just questions to the subject persons and finding whether or not classical rules for conditional probabilities hold true or not. 1. First experiment Bistable percepts induced by ambiguous figures are especially attractive from the point of view of experimentation. The question would be "Which of the two possible percepts?" and the outcome would be answer to this question. The first experiment reported in [2] was following.
2. Second experiment Second experimental test is more complex and involves generalization of Bell's inequality so that it involves conditional probabilities [1] Let A,B,C=+/- be arbitrary dichotomous random variables satisfying Kolmogorov axioms characterizing classical probability. Then the following analog of Bell inequality can be shown to hold true: P(A=+,B=+) + P(C=+,B=-)≥ P(A=+,C=+). In terms of conditional probabilities one has P(A=+/B=+)/P(B=+) + P(C=+/B=-)/P(C=+) ≥ P(A=+/C=+)/P(C=+). If the random variables are symmetrically distributed so that one has P(X=+/-)=1/2, for X=A,B,C one obtains P(A=+/B=+)+P(C=+/B=-)≥ P(A=+/C=+) . Note that this form of equality is by no means necessary. The symmetric distributions for the random variables would however correspond to maximal entanglement in spin system given best hopes for the violation of the Bell inequality.
3. Criticism and possible improvement of the experiment In the case of spin pairs the tests of quantum behavior are carried out for the members of spin pair by putting them to magnetic fields having different directions. Now the pair of experiments is made for a single subject person. Hence there is no need to prepare quantum entangled pair of conscious entities. The use of ensemble is the problematic aspect of experiments. Human beings are extremely complex systems and one can argue that it is impossible to prepare an ensemble of identical systems in cognitive sense. A possible manner to avoid the problem would be the replacement of ensembles with a time series of experiments performed for a single subject person. In both experiments one could perform the two kinds of experiments many times to single subject person and deduce various probabilities and cos(θ) from the outcome of the experiments. 4. Interpretation in terms of zero energy ontology and DNA as tqc The discussions with Elio Conte led to the realization that in zero energy ontology the experiments differ from the corresponding experiments for two-spin system only in that space-like entanglement is replaced with time like entanglement. The experiment would be essentially a measurement of probabilities defined by the matrix elements of M-matrix defining the generalization of S-matrix. Hence Bell's inequalities and their generalizations should apply in genuine quantum sense. By performing the experiments for a single subject person as time series one might be therefore able study whether quantum consciousness in the sense of TGD makes sense. Quantum consciousness approach however requires that bistable percepts have genuine microscopic quantum states as their physical correlates. This is not assumed in the approach of Khrennikov.
References [1] A. Khrennikov (2004), Bell's inequality for conditional probabilities as a test for quantum like behaviour of mind, arXiv:quant-ph/0402169. [2] E. Conte, O. Todarello, A. Federici, J. P. Zbilut (2008), Minds States Follow Quantum Mechanics During Perception and Cognition of Ambigious Figures: A Final Experimental Confirmation, arXiv:0802.1835v1 [physics.gen-ph]. [3] B. Shipman (1998), The geometry of momentum mappings on generalized flag manifolds, connections with a dynamical system, quantum mechanics and the dance of honeybee. B. Shipman (1998), On the geometry of certain isospectral sets in the full Kostant-Toda lattice. B. Shipman (1998), A symmetry of order two in the full Kostant-Toda lattice. |
DNA as topological quantum computer: XIIIn previous postings I, II, III, IV, V, VI, VII, VIII, IX, X, XI I have discussed various aspects of the idea that DNA could acts as a topological quantum computer using fundamental braiding operation as a universal 2-gate. One of the challenges is the realization of single particle gates representing U(2) rotation of the qubit. The first thing to come mind was that U(2) corresponds to U(2) rotation induced by magnetic field and electric fields. Yesterday I realized much more elegant realization in terms of SU(3) rotation, where SU(3) is color group associated with strong interactions. Soon I remembered that there is direct evidence for the prediction that color SU(3) is associated with tqc and thus cognition: something that does not come first in mind! I have myself written text about the strange finding of topologist Barbara Shipman suggesting that quarks are in some mysterious manner involved with honeybee dance and proposed an interpretation. 1. The realization of 1-gate in terms of ordinary rotations The realization of single particle gates as U(2) transformations leads naturally to the extension of the braid group by assigning to the strands sequences of group elements satisfying the group multiplication rules. The group elements associated with a nth strand commute with the generators of braid group which do not act on nth strand. G would be naturally subgroup of the covering group of rotation group acting in spin degrees of spin 1/2 object. Since U(1) transformations generate only an overall phase to the state, the presence of this factor might not be necessary. A possible candidate for U(1) factor is as a rotation induced by a time-like parallel translation defined by the electromagnetic scalar potential Φ=At. A possible realization for single particle gate- characterized by s subset SU(2)- would be as SU(2) rotation induced by a magnetic pulse. This transformation is fixed by the rotation axis and rotation angle around this axes. This kind of transformation would result by applying to the strand a magnetic pulse with magnetic field in the direction of rotation axes. The duration of the pulse determines the rotation angle. Pulse could be created by bringing a magnetic flux tube to the system, letting it act for the required time, and moving it away. U(1) phase factor could result from the electromagnetic gauge potential as a non-integrable phase factor exp(ie∫ Atdt/hbar) coming from the presence of scale potential Φ=At in the Hamiltonian. One can criticize this model. The introduction of magnetic pulses does not look an attractive idea and seems to require additional structures besides magnetic flux tubes (MEs?). It would be much nicer to assign the magnetic field with the flux tubes defining the braid strands. The rotation of magnetic field would however require changing the direction of braid strands. This does not look natural. Could one do without this rotation by identifying spin like degree of freedom in some other manner? This is indeed possible.
2. The realization of 1-gate in terms of color rotations TGD predicts a hierarchy of copies of scaled up variants of both weak and color interactions and these play a key role in TGD inspired model of living matter. Both weak isospin and color isospin could be considered as alternatives for the ordinary spin as a realization of qubit in TGD framework. Below color isospin is discussed. Below color isospin is discussed but one could consider also a realization in terms of nuclei and their exotic counterparts differing only by the replacement of neutral color bond between nuclei of nuclear string with a charged one. Charge entanglement between nuclei would guarantee overall charge conservation.
To sum up, this picture suggests that 1-gates of DNA tqc (understood as "dance of lipids") are defined by color rotations of the ends of space-like braid strands and at lipids. The color rotations would be induced by sensory and other inputs to the system. Topological quantum computation would be directly related to conscious experience and sensory and other inputs would fix the directions of the color magnetic fields. For details see the chapter DNA as Topological Quantum Computer.
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Summary of possible symmetries of DNA suggested by the model of topological quantum computationThe following gives a list of possible symmetries of DNA inspired by the identification of braid color. 1. Color confinement in strong form The states of quarks and anti-quarks associated with DNA both wormhole wormhole throats of braided (living) DNA strand can be color singlets and have thus integer valued anomalous em charge. The resulting prediction depends on the assignment of quarks and antiquarks to A,T,C,G which in principle should be determined by the minimization of em interaction energy between quark and nucleotide. For instance 2(A-T)-(G-C) mod 3=0 for a piece of living DNA which could make possible color singletness. As a matter fact, color singletness conditions are equivalent for all possible for braid color assignments. This hypothesis might be weakened. For instance, it could hold true only for braided parts of DNA and this braiding are dynamical. It could also hold for entire braid with both ends included only: in this case it does not pose any conditions on DNA. Questions: Do all living DNA strands satisfy this rule? Are only the double stranded parts of DNA braided and satisfy the rule. What about loops of hairpins? 2. Matter antimatter asymmetry at quark level A←→ T and G←→ C corresponds to charge conjugation at the level of quarks (quark ←→ antiquark). Chargaff's rules states A≈ T and C≈ G for long DNA strands and mean matter-antimatter symmetry in the scale of DNA strand. Double strand as a whole is matter anti-matter symmetric. Matter-antimatter asymmetry is realized functionally at the level of DNA double strand in the sense that only DNA strand is transcribed. The study of some examples shows that genes defined as transcribed parts of DNA do not satisfy Chargaff's rule. This inspires the hypothesis about the breaking of matter antimatter symmetry. Genes have non-vanishing net A-T and C-G and therefore also net Qa with sign opposite to that in control regions. Just as the Universe is matter-antimatter asymmetric, also genes would be matter-antimatter asymmetric. 3. Isospin symmetry at quark level A←→ G and T←→ A correspond change of anomalous em charge by 1 unit and these operations respect color confinement condition. Local modifications of DNA inducing these changes should be preferred. The identification for the symmetries A←→ G and T←→ A for the third nucleotide of code is as isospin symmetries. For the vertebrate mitochondrial code the symmetry exact and for nuclear code slightly broken. 4. Matter antimatter asymmetry and isospin symmetries for the first two nucleotides The first two nucleotides of the codon dictate to a high degree which amino-acid is coded. This inspires the idea that 3-code has emerged as fusion of 1- and 2-codes in some sense. There are two kinds of 2-codons. The codons of type A have fractional em charge and net quark number (consisting of either matter or antimatter at quark level) and are not able to form color singlets. The codons of type B have integer em charge and vanishing quark number (consisting of matter and antimatter) and are able to form color singlets. The 2-codons of type A (resp. B) are related by isospin rotations and there should be some property distinguishing between types A and B. There indeed is: if 2-codon is matter-antimatter asymmetric, 1-codon is not and vice versa.
5. Em stability Anomalous em charge Qa vanishes for DNA and perhaps also mRNA strand containing also the G cap and poly-A tail which could compensate for the Qa of the transcribed region so that 2(A-T)-(G-C)≈ 0 or some variant of it holds true. Chargaff's rules for long DNA strands imply the smallness of Qa. 6. Summary of testable working hypothesis Following gives a summary of testable working hypothesis related to the isospin symmetry and color singletness. The property of having integer valued/vanishing Qa is referred to as property P.
For a more detailed exposition and background see the chapter DNA as Topological Quantum Computer.
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Transposons and anomalous em chargeTGD based model of tqc relies on colored braids with the color of braid in one-one correspondence with nucleotides A,T,C,G and represented by 2 quarks and 2 anti-quarks. The basic prediction of the braid concept is anomalous em charge defined as the net quark charge assignable to DNA space-time sheets of DNA sequence. This notion makes sense also for more general molecules possessing braids. Transposons provide an especially simple manner to test the hypothesis that anomalous em charge is integer valued (quarks can form color singlet) or even vanishing (by stability). Transposons (see this and the article of D. F. Voytas (2008), Fighting fire with fire, Nature vol 451, January) are moving and copying genes. Moving genes cut from initial position and past to another position of double strand. Copying genes copy themselves first to RNA and them to a full DNA sequence which is then glued to the double strand by cut and paste procedure. They were earlier regarded as mere parasites but now it is known that their transcription is activated under stress situations so that they help DNA to evolve. In tqc picture their function would be to modify tqc hardware. For copying transposons the cutting of DNA strand occurs usually at different points for DNA and cDNA so that "sticky ends" result ("overhang" and its complement) (see ). Often the overhang has four nucleotides. The copied transposon have ends which are reversed conjugates of each other so that transposons are palindromes as are also DNA hairpins. This is suggestive of the origin of transposons./p> In order to avoid boring repetitions let us denote by "satisfy P" for having having integer valued (or even vanishing) Qa. The predictions are following:
It is known that transposons - repeating regions itself - tend to attach to the repeating regions of DNA.
AT and CG have vanishing Qa so that their presence in LINEs and SINEs would make the cutting and pasting easy allowing to understand why transposons favor these regions. Viruses are known to contain long repeating terminal sequences (LTR). One could also check whether DNA decomposes to regions satisfying P and surrounded by repeating sequences which satisfy P separately or as whole as in the case DNA transposons. For a more detailed exposition and background see the chapter DNA as Topological Quantum Computer.
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What selected the bio-molecules?The extremely low probabilities for the selection of bio-molecules from a super-astrophysical number of alternatives represents one of the bottleneck problems of biology relying on the prevailing view about biochemistry. The notion of braid could resolve this problem. Suppose that the presence of braids distinguishes between living and dead matter, that the four nucleotides are mapped to colored braid strands (that is to 2 quarks + 2 anti-quarks), and that a given amino-acid is mapped in a non-deterministic manner to one of the 3-braids associated with the DNA triplets coding for it. Braids could be associated besides DNA, amino-acids, and lipids also to other bio-molecules and define more general analogs of genetic codes as correspondences between bio-molecules able to react. The implication would be that the step of catalytic reactions bringing together the catalyst and reactants would occur by a temporary reduction of Planck constant only for subsets of bio-molecules connected by braid strands and the pattern of braid strands involved would define the geometro-dynamical pattern of the reaction. The outcome would be a selection of very restricted subsets of bio-molecules able to form reaction networks and of reaction pathways. This would imply Darwinian selection of subsets of bio-molecules able to co-exist and dramatically enhance the probability for the emergence of life as we know it. One challenge is to predict what kind of braids can begin from a given bio-molecule, say nucleotide or amino-acid. The physicist's guess would be that the (electromagnetic only?) interaction energy between bio-molecule and given pattern of wormhole contacts having quark and anti-quark at its throats should select the preferred braids as minima of the interaction energy. How closely the presence of hydrogen bonds (and of conjectured "half hydrogen bonds") relates to this is also an interesting question. For the model of DNA as topological quantum computer see the chapter DNA as Topological Quantum Computer.
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Structure and function of tRNA in braid pictureThe recent beautiful results (for a popular summary see [pwpop]) about programming of bio-molecular self assembly combined with the earlier model for the pre-biotic evolution inspire interesting insights about the role of braiding in translation. According to the TGD based model of pre-biotic evolution [prebio], 3-code should have resulted as a fusion of 1- and 2- codes to 3-code involving fusion of tRNA1 and tRNA2 to tRNA. Second hypothesis is that during RNA era the function of tRNA2 was to generate RNA2 double strand from single RNA strand and that amino-acids catalyzed this process. The considerations that follow strongly suggest that tRNA1 was involved with a non-deterministic generation of new RNA sequences essential for the evolution. After the establishment of 3-code these two process fused to a deterministic process generating amino-acid sequences. RNA era could still continue inside cell and play an important role in evolution.
A. Structure of tRNA molecule The structure of tRNA- although more complex than that of hairpin- has much common with that of hairpins. Therefore it is interesting to look this structure from the point of view of TGD. For instance, one can find whether the notions of braiding, anomalous em charge and quark color could provide additional insights about the structure and function of tRNA. The shape of the tRNA molecule [tRNA] in 2-D representation is that of cruciform.
B. Wobble base pairing The phenomenon of wobble base pairing [wobble] is very important. There are only about 40 tRNA molecules instead of 61 which means that one-to-one map between mRNA nucleotides and tRNA conjugate nucleotides is not possible. Crick suggests that so called wobble base pairing resolves the problem. What happens that the first nucleotide of anticodon is either A, G, U, or I(nosine) [inosine]. The base-pairings for third nucleotide are {A-U, G-C, U-{A,G}, I-{U,A,C}. The explanation for the non unique base pairing in the case of U is that its geometric configuration is quite not the same as in ordinary RNA strand. I is known to have 3-fold base pairing. Minimization of the number of tRNAs requiring that only three mRNA codons act as stopping signs predicts that the number of tRNAs is 40.
C. Wobble base pairing in TGD framework Consider first the interpretation of wobble base pairing in TGD framework assuming the braiding picture and the mapping of nucleotides to quarks. The completely symmetric 4-columns correspond to unbroken isospin and matter-antimatter symmetries. 4-columns decomposing into doublets result from the breaking of matter-antimatter symmetry at quark level. ile-met column corresponds to the breaking of both symmetries. The base pairings of I obviously break both symmetries. The non-unique based pairing of U and I means that they cannot correspond to a unique quark or anti-quark in braiding U pairs with both A and G so that the braid strands starting from these RNA nucleotides must both be able to end to tRNA U. Hence tRNA U is not sensitive to the isospin of the quark. This non-uniqueness could relate to the assumed anomalous geometric character of the binding of U codon to tRNA sequence. The braid strands beginning from U, A, and C must be able to end up to I so that I can discriminate only between {U,C,A} and G. D. Anomalous em charge and color singletness hypothesis for tRNA One can test also whether the vanishing of anomalous em charge of tRNA leads to testable predictions. One can also try understand translation process in terms of the braiding dynamics. One must distinguish between the states of tRNA alone and tRNA + amino-acid for which braidings are expected to be different. Before continuing it must be made clear that braiding hypothesis is far from being precisely formulated. One question is whether the presence of the braiding could distinguish between matter in vivo and vitro. For instance, the condition that anomalous em charge is integer valued or vanishing for DNA hairpins in vivo gives strong condition on the loop of the hairpin but or hairpins in vitro there would be no such conditions. Second point is that amino-acids and I and U in tRNA1 could carry variable anomalous em charge allowing rather general compensation mechanism. D.1 tRNA without amino-acid
D.2 tRNA plus amino-acid
E. Triplet code as a fusion of singlet and doublet codes? In [prebio] I have discussed the hypothesis that the standard 3-code has emerged as a fusion of 1-codes with 4 1-codons and 2-code with 16 2-codons. It is interesting to see whether this model is consistent with the braid picture. E.1 tRNA as fusion of tRNA1 and tRNA1 The earlier proposal was that the fusion of 1- and 2-code to 3-code meant (at least) the fusion of tRNA1 and tRNA2 to form a more complex tRNA of 3-code. This process would have involved fusion of 1- and 2-anticodons of tRNA. The visual inspection of tRNA shows that tRNA1 and tRNA2 could have been simple RNA hairpins during pre-biotic evolution. The variable loop associated with the T arm has indeed emerged during evolution and its function is believed to relate to the stability of tRNA [tRNA]. For instance, the anomalous em charge of the variable loop could compensate for the net em anomalous charge of amino-acid-tRNA system. tRNA1 is identifiable as a piece of tRNA extending from 5' end to the first nucleotide (wobble nucleotide) of the anticodon. tRNA2 would contain at its 5'-end 2-codon and plus T arm and second half of the acceptor stem. The simpler structure of D-arm (in particular, the stem involves only 3 codon pairs) conforms with this view. The emergence of tRNA anticodon as a fusion of 1-anticodon and 2-anti-codons could explain the wobble base pairing. The inverse assignment {U→ A, C→ G, {A,G}→ U, {U,A,C}→ I} deduced from the the number 40 of tRNAs and assigning unique 1-codon to only G could be interpreted as a non-deterministic correspondence generating new RNA sequences from existing ones. E.2 The change of the role of amino-acids in the transition from pre-biotic to biotic evolution In [prebio] it was proposed that during RNA era amino-acids catalyzed the replication of 2-RNA to its conjugate and that at some state the role of amino-acids and 2-anti-codons changed and instead of conjugate of 2-RNA strand amino-acid sequence was generated. In braiding picture this transition could be understood as a phase transition changing the dynamics of braiding.
The objection is that the resulting RNA sequences contain A, G, U, and I and are analogous to conjugates of RNA sequences rather than being proper RNA sequences. A possible way out of the problem is to build a conjugate of this sequence using tRNA2. The problem is that if I base pairs with A,T, or C, ne obtains only the codons T,C,A. If U pairs with A and G as in the case of 1-code, also G is obtained. The presence of G*U pairs in tRNA2 suggests that these pairings were indeed present. The presence of I in the tRNA1 induced RNA sequences might prevent their interpretation as genuine RNA sequences, which would imply conjugation symmetry of RNA. The objection is that the resulting RNA sequences contain A, G, U, and I and are analogous to conjugates of RNA sequences rather than being proper RNA sequences. A possible way out of the problem is to build a conjugate of this sequence using tRNA1 again. Since I pairs with A,T, or C and U with A and G and G with G and A with U all nucleotides appear in the resulting sequence. The anomalous G*U base pairs in tRNA could be seen as remnants of RNA era. The presence of I in the tRNA1 induced RNA sequences might prevent their interpretation as genuine RNA sequences, which would imply conjugation symmetry of RNA. There is an additional argument supporting the idea that the coding of amino-acids emerges only after the formation of 3-code. If the 2-code would have coded for amino-acids before the fusion of the codes, the fusion should have involved also the fusion of corresponding RNA sequences in order to guarantee that the resulting 3-RNA sequence still codes for the amino-acids coded by 2-RNA sequences plus some new ones. This kind of fusion is not too plausible although I have considered this possibility in the earlier model [prebio].
F. Was the counterpart of cell membrane present during RNA era? Topological quantum computation should have taken place already during RNA era. This suggest that the counterpart of the cell membrane was present already at that time. Quite recently it was reported that DNA duplexes of length 6 to 20 base pairs can join to longer cylinders which in turn form liquid crystals and that the liquid crystal phase separates from the phase formed by single DNA strands. Long strands had been already earlier known to form liquid crystals. This encourages to think that also RNA duplexes are able to self-organize in this manner so that the analog of cell nucleus containig RNA double helices as genetic material could have existed already during RNA era. The nuclear membranes could have consisted of either ordinary RNA or its variant consisting of A,T,G,I produced by tRNA1. The latter option would allow to distinguish between coding RNA and RNA used as building block of various structures. The sequences consisting of 30 RNA base pairs would correspond to the thickness of cell membrane and to the codon of M61 code. Lipid layer of thickness 5 nm would correspond to roughly 16 base pairs and to the codon assignable to M17. For a more detailed exposition and background see the chapter DNA as Topological Quantum Computer.
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Programming of bio-molecular self assembly pathways from TGD point of viewThere is an interesting work about programming bio-molecular self assembly pathways [Y. Peng Yin et al (2007), Programming biomolecular self-assembly pathways, Nature 451, 318-322 (17 January 2008)]. The catalytic self assembly of complexes of nuclei acids is carried out automatically by a program represented implicitly as a mixture of linear DNA strand acting as catalyst and so called hairpin DNAs containing three nucleation sites at, bt, ct - so called toeholds. A. Key ideas The basic idea is that a set of bio-molecular reactions can be programmed to occur in a desired order by using a generalization of lock and key mechanism. The simplest self assembly pathway can be specified by a collection of keys and locks. In the beginning there is only one key and the this key fits to only one door, which leads into a room with several doors. The lock eats the key but gives one or more keys. If the room contains several doors to which the keys fits, the reaction corresponds to addition of several branches to the already existing reaction product. By continuing in this manner one eventually ends up to the last room and at the last step the lock gives back the original key so that it can act as a catalyst. The translation of this idea to a program defining self assembly pathway is following.
B. TGD view about the situation The possibility to program the self-assembly relies on the almost deterministic realization of the lock and key mechanism. The presence of braid strands could make this possible.
For a more detailed exposition and background see the chapter DNA as Topological Quantum Computer.
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DNA as topological quantum computer: XIIn previous postings I, II, III, IV, V, VI, VII, VIII, IX, X I have discussed various aspects of the idea that DNA could acts as a topological quantum computer using fundamental braiding operation as a universal 2-gate. Since the representation in the book and in previous postings is bottom-up and not well-organized, it is perhaps worth of providing a summary about the model in both bottom-up (very briefly) and top-to-bottom manner. 1. Bottom-up approach I ended up with the third model in bottom-up manner and this representation is followed also in the text. The model which looks the most plausible one relies on two specific ideas.
2. Top-down approach One ends up to the model also in top-down manner.
For details see the chapter DNA as Topological Quantum Computer.
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About the arrow of psychological time and notion of self: once again!Quantum classical correspondence predicts that the arrow of subjective time is somehow mapped to that for the geometric time. The detailed mechanism for how the arrow of psychological time emerges has however remained open. Also the notion of self is problematic. I have proposed two alternative notions of self and have not been able to choose between them. A further question is what happens during sleep: do we lose consciousness or is it that we cannot remember anything about this period? The work with the model of topological quantum computation (see previous posting) has led to an overall view allowing to select the most plausible answer to these questions. But let us be cautious! A. Two earlier views about how the arrow of psychological time emerges The basic question how the arrow of subjective time is mapped to that of geometric time. The common assumption of all models is that quantum jump sequence corresponds to evolution and that by quantum classical correspondence this evolution must have a correlate at space-time level so that each quantum jump replaces typical space-time surface with a more evolved one.
B. The third option The third explanation for the arrow of psychological time - which I have considered earlier but only half-seriously - began to look very elegant during last night. This option is actually favored by Occam's razor since it uses only the assumption that space-time sheets are replaced by more evolved ones in each quantum jump. Also the model of tqc favors it.
I have considered two different notions of "self" and it is interesting to see whether this picture might allow to choose between them.
Could the new option allow to speculate about the course of events at the moment of death? Certainly this particular sensory "me" would effectively meet the geometro-temporal boundary of the biological body: sensory input would cease and there would be no biological body to use anymore. "Me" might lose its consciousness (if it can!). "Me" has also other mental images than sensory ones and these could begin to dominate the consciousness and "me" could direct its attention to space-time sheets corresponding to much longer time scale, perhaps even to that of life cycle, giving a summary about the life. What after that? The Tibetan Book of Dead gives some inspiration. A western "me" might hope (and even try use its intentional powers to guarantee) that quantum Turing tape brings in a living organism, be it human or cat or dog or at least some little bug. If this "me" is lucky, it could direct its attention to it and become one of the very many sensory "me's" populating this particular 4-D biological body. There would be room for a newcomer unlike in the alternative models. A "me" with Eastern/New-Ageish traits could however direct its attention permanently to the dark space-time sheets and achieve what might she might call enlightment. For details see the chapter DNA as Topological Quantum Computer.
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DNA as topological quantum computer: XIn previous postings I, II, III, IV, V, VI, VII, VIII, IX I have discussed various aspects of the idea that DNA could acts as a topological quantum computer using fundamental braiding operation as a universal 2-gate. Many problems of quantum computation in standard sense might relate to a wrong view about quantum theory. If TGD Universe is the physical universe, the situation would improve in many respects. There is the new fractal view about quantum jump and observer as "self"; there is p-adic length scale hierarchy and hierarchy of Planck constants as well as self hierarchy; there is a new view about entanglement and the possibility of irreducible entanglement carrying genuine information and making possible quantum superposition of fractal quantum computations and quantum parallel dissipation; there is zero energy ontology, the notion of M-matrix allowing to understand quantum theory as a square root of thermodynamics, the notion of measurement resolution allowing to identify M-matrix in terms of Connes tensor product; there is also the notion of magnetic body providing one promising realization for braids in tqc, etc... Taking the risk of boring the reader by repeating things that I have already said I will summarize these new aspects TGD below. There is also a second motivation. Quantum TGD and TGD inspired theory of consciousness involve quite a bundle of new ideas and the continual checking of internal consistency by writing it through again and again is of utmost importance. The following considerations can be also seen as this kind of checking. I can only represent apologies to the benevolent reader: this is a work in progress.
A. Fractal hierarchies Fractal hierarchies are the essence of TGD. There is hierarchy of space-time sheets labelled by preferred p-adic primes. There is hierarchy of Planck constants reflecting a book like structure of the generalized imbedding space and identified in terms of a hierarchy of dark matters. These hierarchies correspond at the level of conscious experience to a hierarchy of conscious entities -selves: self experiences its sub-selves as mental images. Fractal hierarchies mean completely new element in the model for quantum computation. The decomposition of quantum computation to a fractal hierarchy of quantum computations is one implication of this hierarchy and means that each quantum computation proceeds from longer to shorter time scales Tn=2-nT0 as a cascade like process such that at each level there is a large number of quantum computations performed with various values of input parameters defined by the output at previous level. Under some additional assumptions to be discussed later this hierarchy involves at a given level a large number of replicas of a given sub-module of tqc so that the output of single fractal sub-module gives automatically probabilities for various outcomes as required.
B. Irreducible entanglement and possibility of quantum parallel quantum computation The basic distinction from standard measurement theory is irreducible entanglement not reduced in quantum jump. B.1 NMP and the possibility of irreducible entanglement Negentropy Maximimization Principle states that entanglement entropy is minimized in quantum jump. For standard Shannon entropy this would lead to a final state which corresponds to a ray of state space. If entanglement probabilities are rational -or even algebraic - one can replace Shannon entropy with its number theoretic counterpart in which p-adic norm of probability replaces the probability in the argument of logarithm: log(pn)→ log(Np(pn). This entropy can have negative values. It is not quite clear whether prime p should be chosen to maximize the number theoretic negentropy or whether p is the p-adic prime characterizing the light-like partonic 3-surface in question. Obviously NMP favors generation of irreducible entanglement which however can be reduced in U process. Irreducible entanglement is something completely new and the proposed interpretation is in terms of experience of various kinds of conscious experiences with positive content such as understanding. Quantum superposition of unitarily evolving quantum states generalizes to a quantum superposition of quantum jump sequences defining dissipative time evolutions. Dissipating quarks inside quantum coherent hadrons would provide a basic example of this kind of situation. B.2 Quantum parallel quantum computations and conscious experience The combination of quantum parallel quantum jump sequences with the fractal hierarchies of scales implies the possibility of quantum parallel quantum computations. In ordinary quantum computation halting selects single computation but in the recent case arbitrarily large number of computations can be carried out simultaneously at various branches of entangled state. The probability distribution for the outcomes is obtained using only single computation. One would have quantum superposition of space-time sheets (assignable to the maxima of Kähler function) each representing classically the outcome of a particular computation. Each branch would correspond to its own conscious experience but the entire system would correspond to a self experiencing consciously the outcome of computation as intuitive and holistic understanding, abstraction. Emotions and emotional intellect could correspond to this kind of non-symbolic representation for the outcome of computation as analogs for collective parameters like temperature and pressure. B.3 Delicacies There are several delicacies involved.
C.Connes tensor product defines universal entanglement Both time-like entanglement between quantum states with opposite quantum numbers represented by M-matrix and space-like entanglement reduce to Connes tensor dictated highly uniquely by measurement resolution characterized by inclusion of HFFs of type II1
C.1 Time-like and space-like entanglement in zero energy ontology If hyper-finite factors of II1 are all that is needed then Connes tensor product defines universal S-matrix and the most general situation corresponds to a direct sum of them. M-matrix for each summand is product of Hermitian square root of density matrix and unitary S-matrix multiplied by a square root of probability having interpretation as analog for Boltzmann weight or probability defined by density matrix (note that it is essential to have Tr(Id)=1 for factors of type II1. If factor of type I∞ are present situation is more complex. This means that quantum computations are highly universal and M-matrices are characterized by the inclusion N subset M in each summand defining measurement resolution. Hermitian elements of N act as symmetries of M-matrix. The identification of the reducible entanglement characterized by Boltzmann weight like parameters in terms of thermal equilibrium would allow interpret quantum theory as square root of thermodynamics. If the entanglement probabilities defined by S-matrix and assignable to N rays do not belong to the algebraic extension used then a full state function reduction is prevented by NMP. Ff the generalized Boltzmann weights are also algebraic then also thermal entanglement is irreducible. In p-adic thermodynamics for Virasoro generator L0 and using some cutoff for conformal weights the Boltzmann weights are rational numbers expressible using powers of p-adic prime p. C.2 Effects of finite temperature Usually finite temperature is seen as a problem for quantum computation. In TGD framework the effect of finite temperature is to replace zero energy states formed as pairs of positive and negative energy states with a superposition in which energy varies. One has an ensemble of space-time sheets which should represent nearly replicas of the quantum computation. There are two cases to be considered.
If the degrees of freedom assignable to topological quantum computation do not depend on the energy of the state, thermal width does not affect at all the relevant probabilities. The probabilities are actually affected even in the case of tqc since 1-gates are not purely topological and the effects of temperature in spin degrees of freedom are unavoidable. If T grows the probability distribution for outcomes flattens and it becomes difficult to select the desired outcome as that appearing with maximal probability. D. Possible problems related to quantum computation At least following problems are encountered in quantum computation.
D.1 The notion of coherence region in TGD framework In standard framework one can speak about coherence in two senses. At the level of Schrödinger amplitudes one speaks about coherence region inside which it makes sense to speak about Schrödinger time evolution. This notion is rather defined. In TGD framework coherence region is identifiable as inside which modified Dirac equation holds true. Strictly speaking, this region corresponds to a light-like partonic 3-surface whereas 4-D space-time sheet corresponds to coherence region for classical fields. p-Adic length scale hierarchy and hierarchy of Planck constants means that arbitrarily large coherence regions are possible. The precise definition for the notion of coherence region and the presence of scale hierarchies imply that the coherence in the case of single quantum computation is not a problem in TGD framework. De-coherence time or coherence time correspond to the temporal span of space-time sheet and a hierarchy coming in powers of two for a given value of Planck constant is predicted by basic quantum TGD. p-Adic length scale hypothesis and favored values of Planck constant would naturally reflect this fundamental fractal hierarchy. D.2 De-coherence of density matrix and replicas of tqc Second phenomenological description boils down to the assumption that non-diagonal elements of the density matrix in some preferred basis (involving spatial localization of particles) approach to zero. The existence of more or less faithful replicas of space-time sheet in given scale allows to identify the counterpart of this notion in TGD context. De-coherence would mean a loss of information in the averaging of M-matrix and density matrix associated with these space-time sheets. Topological computations are probabilistic. This means that one has a collection of space-time sheets such that each space-time sheet corresponds to more or less same tqc and therefore same M-matrix. If M is too random (in the limits allowed by Connes tensor product), the analog of generalized phase information represented by its "phase" - S-matrix - is useless. In order to avoid de-coherence in this sense, the space-time sheets must be approximate copies of each other. Almost copies are expected to result by dissipation leading to asymptotic self-organization patterns depending only weakly on initial conditions and having also space-time correlate. Obviously, the role of dissipation in eliminating effects of de-coherence in tqc would be something new. The enormous symmetries of M-matrix, the uniqueness of S-matrix for given resolution and parameters characterizing braiding, fractality, and generalized Bohr orbit property of space-time sheets, plus dissipation give good hopes that almost replicas can be obtained. D.3 Isolation and representations of the outcome of tqc The interaction with environment makes quantum computation difficult. In the case of topological quantum computation this interaction corresponds to the formation of braid strands connecting the computing space-time sheet with space-time sheets in environment. The environment is four-dimensional in TGD framework and an isolation in time direction might be required. The space-time sheets responsible for replicas of tqc should not be connected by light-like braids strands having time-like projections in M4. Length scale hierarchy coming in powers of two and finite measurement resolution might help considerably. Finite measurement resolution means that those strands which connect space-time sheets topologically condensed to the space-time sheets in question do not induce entanglement visible at this level and should not be affect tqc in the resolution used. Hence only the elimination of strands responsible for tqc at given level and connecting computing space-time sheet to space-time sheets at same level in environment is necessary and would require magnetic isolation. Note that super-conductivity might provide this kind of isolation. This kind of elimination could involve the same mechanism as the initiation of tqc which cuts the braid strands so the initiation and isolation might be more or less the same thing. Strands reconnect after the halting of tqc and would make possible the communication of the outcome of computation along strands by using say em currents in turn generating generalized EEG, nerve pulse patterns, gene expression, etc... halting and initiation could be more or less synonymous with isolation and communication of the outcome of tqc. D.4 How to express the outcome of quantum computation? The outcome of quantum computation is basically a representation of probabilities for the outcome of tqc. There are two representations for the outcome of tqc. Symbolic representation which quite generally is in terms of probability distributions represented in terms "classical space-time" physics. Rates for various processes having basically interpretation as geometro-temporal densities would represent the probabilities just as in case of particle physics experiment. For tqc in living matter this would correspond to gene expression, neural firing, EEG patterns,... A representation as a conscious experience is another (and actually the ultimate) representation of the outcome. It need not have any symbolic counterpart since it is felt. Intuition, emotions and emotional intelligence would naturally relate to this kind of representation made possible by irreducible entanglement. This representation would be based on fuzzy qubits and would mean that the outcome would be true or false only with certain probability. This unreliability would be felt consciously. In the proposed model of tqc the emergence of EEG rhythm (say theta rhythm) and correlated firing patterns would correspond to the isolation at the first half period of tqc and random firing at second half period to the sub-sequent tqc:s at shorter time scales coming as negative powers of 2. The fractal hierarchy of time scales would correspond to a hierarchy of frequency scales for generalized EEG and power spectra at these scales would give information about the outcome of tqc. Synchronization would be obviously an essential element in this picture and could be understood in terms of classical dynamics which defines space-time surface as a generalized Bohr orbit. Tqc would be analogous to the generation of a dynamical hologram or "conscious hologram" (see this). EEG rhythm would correspond to reference wave and the contributions of spikes to EEG would correspond to the incoming wave interfering with it. Two remarks are in order. D.5 How data is feeded into submodules of tqc? Scale hierarchy obviously gives tqc a fractal modular structure and the question is how data is feeded to submodules at shorter length scales. There are are certainly interactions between different levels of scale hierarchy. The general ideas about master-slave hierarchy assigned with self-organization support the hypothesis that these interactions are directed from longer to shorter scales and have interpretation as a specialization of input data to tqc sub-modules represented by smaller space-time sheets of hierarchy. The call of submodule would occur when the tqc of the calling module halts and the result of computation is expressed as a 4-D pattern. The lower level module would start only after the halting of tqc (with respect to subjective time) and the durations of resulting tqcs would come as Tn= 2-nT0 that geometric series of tqcs would become possible. There would be entire family of tqcs at lower level corresponding to different values of input parameters from calling module. D.6 The role of dissipation and energy feed Dissipation plays key role in the theory of self-organizing systems. Its role is to serve as a Darwinian selector. Without an external energy feed the outcome is a situation in which all organized motions disappear. In presence of energy feed highly unique self-organization patterns depending very weakly on initial conditions emerge. In case of tqc one function of dissipation would be to drive the braidings to static standard configurations, prevent over-braiding, and perhaps even effectively eliminate fluctuations in non-topological degrees of freedom. Note that magnetic fields are important for 1-gates. Magnetic flux conservation however saves magnetic fields from dissipation. External energy feed is needed in order to generate new braidings. For the proposed model of cellular tqc the flow of intracellular water induces the braiding and requires energy feed. Also now dissipation would drive this flow to standard patterns coding for tqc programs. Metabolic energy would be also needed in order to control whether lipids can move or not by generating cis type unsaturated bonds. For the model of DNA as topological quantum computer see the chapter DNA as Topological Quantum Computer.
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