Monday, April 28, 2014

Possible implications of Pollack's findings for pre-biotic life in TGD Universe

I discussed in previous posting the fourth phase of water whose existence is convincingly demonstrated by Gerald Pollack and known with many other names: one of them is Brown's gas known for a long time - standard scientists have refused to admit its existence. In TGD framework the fourth phase of water has nice interpretation in terms of magnetic body and dark proton strings at its flux tubes giving rise to a realization of genetic code. If the fourth phase of water defines pre-biotic life form then the phase transition generating fourth phase of water and its reversal are expected to be fundamental elements of the ordinary metabolism, which would have developed from the pre-biotic metabolism. The following argument demonstrates that the findings of Pollack interpreted in this manner allow to understand what happens in photosynthesis and metabolism at deeper level and also shed light to the newest dramatic discovery related to metabolic pathways.

  1. Cell interiors, in particular the interior of the inner mitochondrial membrane are negatively charged as the regions formed in Pollack's experiments. Furthermore, the citric acid cycle, which forms the basic element of both photosynthesis and cellular respiration, involves electron transport chain in which electron loses gradually its energy via production of NADP and proton at given step. Protons are pumped to the other side of the membrane and generates proton gradient serving as metabolic energy storage just like battery. The interpretation for the electron transport chain in terms of Pollack's experiment would be in terms of generation of dark protons at the other side of the membrane.

  2. When ATP is generated from ADP three protons per ATP flow back along the channel formed by the ATP synthase molecule (perhaps Josephson junction) and rotate the shaft of a "motor" acting as a catalyst generating three ATP molecules per turn by phosphorylating ADP. The TGD based interpretation is that dark protons are transformed back to ordinary ones and possible negentropic entanglement is lost.

  3. ATP is generated also in glycolysis, which is ten-step process occurring in cytosol so that membrane like structure need not be involved. Glycolysis involves also generation of two NADH molecules and protons. An open question (to me) is whether the protons are transferred through an endoplasmic reticulum or from a region of ordered water (fourth phase of water) to its exterior so that it would contribute to potential gradient and could go to magnetic flux tubes as dark proton. This would be natural since glycolysis is realized for nearly all organisms and electron transport chain is preceded by glycolysis and uses as input the output of glycolysis (two pyruvate molecules).

  4. Biopolymers - including DNA and ATP - are typically negatively charged. They could thus be surrounded by fourth phase of water and neutralizing protons would reside at the magnetic bodies. This kind of picture would conform with the idea that the fourth phase (as also magnetic body) is fractal like. In phosphorylation the metabolic energy stored to a potential difference is transferred to shorter length scales (from cell membrane scale to molecular scale).

One of the basic questions of biology is whether metabolism preceded basic biopolymers or vice versa. RNA world scenario assumes that RNA and perhaps also genetic code was first.
  1. The above view suggests that both approaches are correct to some degree in TGD Universe. Both metabolism and genetic code realized in terms of dark proton sequences would have emerged simultaneously and bio-chemistry self-organized around them. Dark proton sequences defining analogs of amino-acid sequences could have defined analogs of protein catalysts and played a key role in the evolution of the metabolic pathways from the primitive pathways involving only the phase transition between ordinary water and fourth phase of water.

  2. There is very interesting article telling that complex metabolic pathways are generated spontaneously in laboratory environments mimicking hot thermal vents. Glycolysis and pentose phosphate pathway were detected. The proposal is that these pathways are catalyzed by metals rather than protein catalysts.

  3. In standard biology these findings would mean that these metabolic pathways emerged before basic biopolymers and that genetic code is not needed to code for the metabolic pathways during this period. In TGD framework dark genetic code would be there, and could code for the dark pathways. Dark proton strings in one-one correspondence with the amino-acid sequences could be responsible for catalysts appearing in the pathways. Only later these catalysts would have transformed to their chemical counterparts and might be accompanied by their dark templates. One cannot even exclude the possiblity that the chemical realization of the DNA-aminoacid correspondence involves its dark analog in an essential manner.
For details see the chapter Meditation, Mind-Body Medicine and Placebo: TGD point of view of "TGD based view about living matter and remote mental interactions" or the article Pollack's findings about fourth phase of water: TGD view.

Saturday, April 12, 2014

What is EEG made of?

The usual classification of EEG frequencies by EEG bands is more or less a convention and the definitions of various bands vary in frustratingly wide ranges. In a more ambitious approach bands should be replaced with some substructures identified on basis of their physical origin and function. In the proposed framework this is possible. This identification of substructures of course applies only to that part of EEG from which evoked potentials, noise, and possible other contributions are subtracted.

In the article What is EEG made of? a TGD inspired model for EEG as a communication and control tool of magnetic body is discussed.

  1. Sensory data are communicated from cell membrane to magnetic body as Josephson radiation and induced transitions at harmonics of cyclotron frequencies determined by the mass number A and charge Z of ion in question (also electron and proton are included) plus the local strength of the magnetic field Bend having nominal value Bend=.2 Gauss in the simplest situation.

    Communications take place at resonance so that one has fJ= ZeV/heff=fc= ZeBend/2πAmp, heff=2k× A× h, where A is the atomic weight of the ion for the fundamental frequencies a more general resonance condition for harmonics reads as mfJ=nfc. This condition is a new ingredient to the earlier model and is extremely restrictive - especially so if one assumes only bosonic ions forming Bose-Einstein condensates. Also electron and proton are needed to represent frequencies which are of order kHz or higher: this is true for hearing for which frequency range to be represented varies up 20 kHz.

  2. Information is coded in frequency modulations of Josephson frequency induced by neural activity and feedback from the magnetic body coming via DNA at harmonics of cyclotron frequencies. Frequencymodulations have emotional content in music, which suggests that the "sensory experiences" of magnetic body defined by the Josephson radiation have emotional content dictated by the frequency modulation.

    Also the variations of resting potential induces frequency modulations and the quantum model for hearing suggests that the variations of the voltage could define analog of music scale consisting of discrete spectrum of resting potentials corresponding to cyclotron frequencies of ions belonging to the octave 10-20 Hz and having frequencies fc∼ 10 Hz in alpha band as basic frequency.

  3. Basic facts about EEG at various stages of sleep and the fact that octaves of 10 Hz frequency appear as resonance frequencies together with music metaphor suggests that EEG can be regarded as superposition of frequencies spectra very much analogous to frequency spectra associated with music scale. In particular, octaves of heff=2km and Bend suggested also by p-adic length scale hypothesis appear. In the simplest situation the EEGs associated with various ions would be time scaled versions of each other making possible "stories" as representations of same events in various time scales: this is believed to be a basic ingredient of intelligence.

  4. The model leads to a detailed identification of sub-bands of EEG in terms of cyclotron frequencies assignable to bosonic ions. One can understand the basic features of various EEG bands, why conscious experiences possible occurring during sleep are not remembered and the four stages of sleep, why beta amplitudes are low and tend to be chaotic, the origin of resonance frequencies of EEG. Also a model for how Schumann resonances could affect consciousness emerges.

    Music metaphor allows to develop in more detail the earlier proposal that nerve pulse patterns defined a languages with "phonemes" having duration of .1 seconds and obeying genetic code with 6 bits. Also the right brain signs metaphor can be given a detailed quantitative content in terms of the analog of music scale associated with the resting potential.

To sum up, the model gives very strong quantitative support for the notion of magnetic body and makes several testable predictions.

For background and details see the chapter Quantum model for EEG or the article What is EEG made of?.

Tuesday, April 08, 2014

Still about TGD and inflation

Quantum criticality is the TGD counterpart of the inflation and the flatness of 3-space follows from the condition that no local dimensional quantities are present in 3-geometry. Also the imbeddability fo M4 is an important piece of story and restricts the set the parameters of imbeddable cosmologies dramatically.

One can try to understand the situation microscopically in terms of the cosmic strings which gradually develop higher than 2-D M4 projection during cosmic evolution and become magnetic flux tubes carrying magnetic monopole fluxes explaining the presence of magnetic fields in cosmology.

At microscopic level magnetic flux tubes are the key structural elements. The phase transitions increasing Planck constant for the matter associated with flux tubes and thus also the lengths of magnetic flux tubes should be important as also the phase transitions increasing p-adic prime and reducing Planck constant originally emerged in the modelling of TGD inspired quantum biology are highly suggestive. First transitions would mean adiabatic expansion with no heat generation and latter transitions would liberate magnetic field energy since flux conservation forces field strength to be reduced and leads to liberation of magnetic energy producing ordinary matter and dark matter. Dark energy in turn is identifiable as magnetic energy.

The key question concerns the mechanism causing the isotropy and homogeny of the cosmology. There are two possible identifications.

  1. According to two decades old TGD proposal primordial cosmology before the emergence of space-time sheets could be regarded as string gas in M4+× CP2 at Hagedorn temperature determined by CP2 radius: TH∼ hbar/R(CP2). This phase could be present also after the transition to radiation dominated cosmology and consist of strings, whose thickness is gradually increasing and which contain carry dark energy and dark matter. The horizon radius is infinite for this cosmology thus providing at least partial explanation for the homogeny and isotropy and visible matter would represent deviations from it.

  2. The accelerating expansion period towards the end of the critical period could smooth out inhomogenities and thus provide an additional mechanism leading to homogenous and isotropic Big Bang. This for given space-time sheet representing R-W cosmology: in many-sheeted cosmology one can imagine distribution of parameters for the cosmology. The rapid expansion period could however also develop large fluctuations! Indeed, the time aF<a1 (density would be infinite for a1) for its end - and therefore local mass density - must have a distribution after the rapid expansion ends. This expansion would generate separate smoothed out radiation dominated space-time sheets with slightly different mass densities and cosmic temperatures. A splitting to smooth radiation dominated sub-cosmologies would take place.

Therefore TGD scenario could be very different from inflationary scenario. The problem is to decide which option is the most feasible one.

The formulas used to make back of the envelope (see this) calculations in inflation theory discussed in a guest posting in Lubos's blog given some idea about TGD counterpart for the generation of gravitons. Inflationary period is replaced with essentially unique critical cosmology containing only its duration as a free parameter. The fluctuations in the duration of this parameter explain scalar temperature fluctuations assoiated with CMB.

How the local polarization of CMB is generated?

There is a nice discussion about the mechanism leading to the generation of CMB polarization (see this). The polarization is generated after the decoupling of CMB photons from thermal equilibrium and is due to the scattering of photons on free electrons during decoupling. This scattering is known as Thomson scattering. The page in question contains schematic illustrations for how the polarization is generated. The scattering from electrons polarizes the photons in direction orthogonal to the scattering plane. In thermal equilibrium the net polarization of scattered radiation vanishes. If however the scattered photons from two perpendicular directions have different intensities a net polarization develops.

Polarized photons could be produced only during a short period during recombination scattering from free electrons was still possible and photons could diffuse between regions with different temperature. Polarized photons were generated when electrons from hot and cold regions where scattering on same electrons. CMB polarization indeed varies over sky but not in long length scales since photons could not diffuse for long lengths.

So called quadrupole anisotropy of CMB temperature contains information about the polarization. There are three contributions: scalar, vector, and tensor.

  1. Scalar contributions is due to density fluctuations reflecting themselves as temperature fluctuations and does not distinguish between polarizations: this is what has been studied mostly hitherto. A natural TGD mechanism for their generation would be different time for the end of the critical period leading to splitting of critical cosmology to radiation dominated cosmologies with slightly different temperatures.

  2. There is also so called vorticity distribution due to the flow which has vorticity and would due to defects/string like objects present also in TGD. The simplified situation corresponds to are region in which one has two flows in opposite direction locally. Depending on whether the scattering photons are upstream or down stream they are blue-shifted or red-shifter so that the temperatures are slightly different in up-stream and down.The flows in opposite direction give rise to a situation in which photons with different temperatures scatter and produce polarization. The effects of vorticity are expected to disappear during the fast expansion period. Probably because the gradients of velocity giving rise to vorticity are smoothed out.

  3. The third contribution is tensor contribution and due to gravitons generating stretching and squeezing of space in two orthogonal directions defining polarization tensor. Stretching increases wavelengths and decreases temperature. Squeezing does the opposite. Therefore temperature differences distinguishing between the two directions are generated and the outcome is polarization of the CMB background much later. This corresponds to the so called E and B modes.

    One can decompose polarization as vector field to two parts: the first one - the E-mode - is gradient and thus irrotational and second is curl and thus rotational and with vanishing divergence (incompressible liquid flow is a good concrete example).

How the polarization anisotropies could be generated in TGD Universe?

One can try to understand microscopically how the polarization anisotropies are generated in TGD framework using poor man's arguments.

  1. One can introduce a vision vision about fractal 3-D network of cosmic strings forming a kinds of grids with nodes in various scales. These grids would be associated with different levels of the hierarchy of space-time sheets associated with many-sheeted space-time. Coordinate grid is of course an idealization since three coordinate lines would meet in single node. A weaker form of grid would involve meeting of two coordinate lines at given node. There is data about our own galactic nucleus understood if it correspond to the node at which two magnetic flux tubes meet. Ordinary visible matter would be generated in nodes.

    One might say that galaxies are due to traffic accidents in which dark matter arriving along two cosmic strings collides in the crossing of the roads. Flux tubes would be attracted together by gravitational attraction so from the crossing.

  2. Amusingly, the notion grid emerged also TGD inspired quantum biology as a proposal for how living system codes morphogenetic position information. Flux tubes carry dark matter and ordinary matter is associated with the nodes at which coordinate lines meet each other. This web can give rise to a generalization of topological quantum computation using 2-braids. Coordinate lines define strings which can be knotted in 3-dimensions and define braids making possible topological quantum computation using macroscopic quantum phases defined by the dark matter. The time evolutions of coordinate lines defines string world sheets and in 4-D space-time the string world sheets can be knotted and braided so that also higher level TQC becomes possible with string reconnection and going above or below the other define two bits in each node.

  3. The presence of grid could also explain the honeycomb like structure of Universe with the recent typical size of honeycomb about 108 ly.

  4. In this framework the illustrations for how the gravitational waves induce the polarization of CMB. The radiation beams entering from opposite directions can be assigned with two magnetic flux tubes meeting at the node and in slightly different temperatures due to the interaction with gravitons much earlier. The gravitons can be regarded as larger space-time sheets at which the two flux tubes had contacts so that space associated with the flux tubes was forced to stretch or squeeze. This in turn increased of reduced photon wavelength so that photon temperature at flux tubes was different and the difference were preserved during subsequent evolution.

Back on the envelope calculations in TGD framework

One can modify the back on the envelope calculations of John Preskill (see this) in Lubos's blog to see what could happen in TGD framework. Now one however starts from the critical cosmology fixed apart from its duration and looks what it gives rather than starting from Higgs potential for inflaton field. The obvious counterpart for inflaton scalar field would be magnetic field intensity having same dimension but one should avoid too concrete correspondences.

The key question is whether the critical period generates the rapid expansion smoothing out inhomogenities or whether it generates them. The original guess that it smooths them out turns out be wrong in closer examination.

  1. The basic equation in inflationary model is given by

    (da/dt)2= V/mp2

    If V is small this has as solution a(t)= a(0)exp(Ht) if H= V1/2/mp is constant. De Sitter cosmology allows partial imbedding in TGD but the imbedding is naturally static and has interpretation as black-hole interior with constant mass density. One can find coordinates in which the solution looks like expanding cosmology without Big Bang but these coordinates are not natural from the view of imbedding space.

  2. In TGD the expression for da/dt for critical cosmology is

    da/dt= [a02-a2]1/2/[a02-R2-a2]1/2 .

    a0 is roughly the duration of cosmology and R is CP2 radius of order 103.5 Planck lengths. The almost uniqueness follows from the condition that the imbedding is such that the induced metric at the 3-surfaces defined by intersections with hyperboloids of M4+ is flat rather than hyperbolic. This cosmology differs from de-Sitter cosmology.

  3. For a→ 0 one has

    da/dt ≈ a02/[a02-R2]≈ 1 .

    so that one has da/dt ≈ 1 and a≈ t for small values of a in accordance with the replacement of Big Bang with a "silent whisper amplified to a Big Bang" (density of matter goes as 1/a2) Hubble constant goes like H∝ 1/a so that Hubble radius divergence. This does not guarantee that horizon radius becomes infinite. Rather, the horizon is finite and given in good accuracy by the duration a1=[a02 R2]1/2 of the period. One can however explain the isotropy and homogenity of the string gas in light-cone M4+ carrying flux tubes carrying dark matter and energy in terms of the infinite horizon of M4.

    There is no exponential time evolution at this period since one has a≈ t in good approximation for a/a0<<1. The TGD counterpart of V would behave like 1/a2, which conforms with the idea that V corresponds to energy density.

  4. As the limit a→ a1=[ta02-R2]1/2 is approached, the expansion rate approaches infinite and for a>a1 at the latest one expects radiation dominated cosmology: otherwise a region of Euclidian signature of the induced metric results. The expectation is that a transition to radiation dominated cosmology takes place before a=a1 at which also energy density would diverge. The question is whether this period means smoothing out of inhomogenities or generation of them or both.
Consider now what could happen near the end of the Minkowskian period of critical cosmology.
  1. Although it is not clear whether rapidly accelerating expansion is needed to to smooth out homogenities, one can just find what conditions this would give on the parameters. For ai= kR at which phase transition began the condition that a was increased at least by factor e50∼ 5× 1021 (50 e-folds) this would give a1≈ a0>e50kR. For k∼ 1 this gives something like 10-18 seconds, which happens to correspond atomic length scale. Below it will be found that this period more naturally corresponds to the period during which large fluctuations in density distribution and metric are generated.

  2. The earlier estimate for the emergence of radiation dominated cosmology assumed that the transition to radiation dominated cosmology takes place at CP2 temperature defining Hagedorn temperature at which temperature of the string gas cannot be raised anymore since all the energy goes to the generation of string excitations rather than to kinetic energy, gives aF∼ 10-10 seconds, which is by factor 108 larger. If this were true, the fast expansion period aF would increase the scale factor to about 68 e-folds equivalent to 98 2-folds. p-Adic prime p≈ 2196 would correspond to p-adic length scale about L(196) ∼ .1 meters. The crucial assumption would be that the the time aF at which the expansion ends is same everywhere. There is no reason to assume this and this would mean that the period in question generates inhomogenities and isotropies of mass distribution and temperature distribution.

    Note that if the distribution of the time aF<a1 at which the critical period ends is responsible for the CMB fluctuations then the number of foldings characterizes the smoothness of given local radiation dominated cosmology and could be rather large.

  3. The rapid accelerating expansion occurs as gaa approaches zero. Indeed, for

    a→ a1= [a02-R2]1/2

    a very rapid expansion occurs and da/dt approaches infinite value. Near to a1 one can write a/a1=1-δ and solve δ approximately as function of t as

    δ =[3R2/4a12]2/3 [t-t1/a1]2/3 ,
    t1= ∫0a1 [1-a2/a121/2/[1-a2/a12]1/2 .

    Hubble constant behaves as

    H= (da/dt)/a = (R2/2a13-1/2 .

  4. What is interesting is that applying the naive dimensional estimate for the amplitude of gravitational fluctuations to be δ hT2∼ H2/mP4. This would mean that at the limit a→ aF< a1 gravitational fluctuations become very strong and generate the strong graviton background. Same applies to fluctuations in mass density.


The possibility of very rapid expansion near a=aF<a1 leading to radiation dominated cosmology should have some deep meaning. The following tries to catch this meaning.

  1. The explosive period could lead to a radiation dominated cosmologies from string dominated cosmology with Hagedorn temperature. It could involve heff increasing phase transitions for string gas during the initial period and liberation of magnetic energy during the end period as massless particles: this would explain why the mass density of the space-time sheet increases dramatically. The critical cosmology could correspond to a phase transition from a phase with Hagedorn temperature identified as TH∝ hbar/RH to radiation dominated cosmology.

  2. The cooling of string gas would lead to the generation of hierarchy of Planck constants and liberation of the magnetic energy of strings as massless particles during the end of critical period topologically condensing to space-time sheets such as massless extremals. This process could correspond to the rapid increase of energy density towards the end of the critical period.

  3. Isotropy and homogenity appear both at the level of imbedding space and space-time sheets. The infinite horizon of M4+ would explain the isotropy and homogenity of string gas in H both before and after the emergence of space-time sheets at Hagedorn temperature around a∼ R(CP2). In particular, the smoothness of the cosmology of dark matter and dark energy would find explanation. The rapid expansion would in turn smooth out inhomogenities of individual space-time sheets.

  4. The Hubble scale 1/H approaches to zero as a=aF<a1 is approached. The rapid expansion destroys anisotropies and inhomogenities of radiation dominated space-time sheet corresponding to particular value of aF. The distribution for values of aF in turn explains CMB scalar fluctuations since the energy density in final state is highly sensitive to the precise value of aF. This distribution would be Gaussian in the first approximation. One can say that the fluctuation spectrum for inflaton field is replaced with that for aF.

  5. Also the generation of gravitational radiation and its decoupling from matter could take place during the same end period. After this gravitational fields would be essentially classical and assignable to space-time sheets. Essentially formation of gravitationally bound states would be in question analogous to what happens photons decouple from matter much later. The reduction of the temperature of string gas below Hagedorn temperature could generate also the massless graviton phase decoupling from matter and inducing the temperature fluctuations and polarization during decoupling.

    Gravitons and also other particles would topological condense at "massless extremals" (MEs,topological light rays) and particles - in particular photons - would interact with gravitons by generating wormhole contacts to gravitonic MEs. The interaction between MEs assignable to gravitational radiation and photons would have caused the fluctuations of CMB temperature.

To sum up, if the TGD inspired picture is correct then Penrose would have been correct in the identification of string theory as fashion and inflationary cosmology as fantasy ( Lubos has reacted strongly to this). Also the fact that inflationary cosmology is at the verge of internal contradiction due the fact that the assumption of field theoretic description is in conflict with the large graviton background suggests that inflationary cosmology is not for long with us anymore.

For details see the chapter TGD and Cosmology or the article BICEP2 might have detected gravitational waves.

Wednesday, April 02, 2014

Do we live in hologram?

Sabine Hossenfelder wrote and excellent posting about holographic principle was motivated by a Youtube hype stating that "Many physicists now believe that reality is not in fact, 3-dimensional". This type of "many/leading physicists believe now" hook has become familiar from science lobbying. Sabine makes it clear that the holography principle is strongly theory dependent proposal.

Lubos reacted strongly to Sabine's comments and wrote a response full of negative emotions. It is a pity, since this posting was preceded by several excellent guest posts about Bicep2 discovery of evidence for gravitational radiation in microwave background: also Lubos wrote a nice post about the topic. I am just wondering why Lubos cannot get his emotional brain in control to avoid this kind of flops.

Lubos did the usual mud slinging with a lof of "silly":s and other similar attributes. Lubos even accused Sabine for being creationist. Towards the end Lubos's emotional brain took the lead totally and he closed the posting with a series of personal insults. Lubos writes otherwise excellently and could become a good science journalist if he only could get his aggressions in control and widen his rather narrow intellectual horizon limited by blind beliefs in string theory, supersymmetry in standard sense, in Boltzmann's thermodynamics as a final truth, recent mainstream interpretation of quantum mechanics, etc...

Is holography principle true?

A fictitious character Q starts a discussion with Sabine by posing the following question.

Q: Do we really live in hologram?

Sabine reacts to "really" and quite correctly states that its content is far from clear. "Reality" indeed leads to long philosophical discussions. Sadly, most colleagues see these discussions as esoterism. It is a pity since this attitude has halted the development of theoretical physics for almost a century. This kind of discussions were possible during the first year of quantum theory but should have been continued.

To specify what "we" means requires a quantum theory of consciousness and of life and I can only refer to the 9 books concerning the TGD view about "really" and "view" (see this)!

A more technical formulation avoiding "we"s and "realities" would be following.

Q: Is holography principle true?

And to avoid the misleading impression that there exists some universally accepted form of this principle as science lobbyist would want us to believe Q should ask:

Q: Could some form form of holography principle be true?

  1. Sabine quite correctly states that gravitational holography principle is a specific conjecture stimulated by AdS/CFT correspondence introduced by Maldacena and being inspired by string model. It relates conformal quantum field theory ( N=4 SUSY) at the 4-D boundary of AdS5, which is 4-D conformally compactified Minkowski space to string model in 10-D AdS5× S5. These assumptions are very strong and not generally true in quantum field theories - say standard model. Lubos claims that a fundamental physical principle is in question. One must of course notice that now hologram is 4-D Minkowski space and something totally different from 2-D hologram provided by say black-hole horizon. A lot of conceptual sloppiness is involved with holography hyping.

  2. Space-time according to standard cosmology is not conformally compactified M4 and standard model is not conformally invariant theory so that holography in the sense AdS/CFT correspondence is a rather specific conjecture! Certainly not a fundamental principle.

    Lubos however states without any justification that this conjecture can be applied also to AdS4 that we habit. This statement of Lubos contains several bad inaccuracies since AdS4 represents inflationary cosmology in the first approximation, and inflationary cosmology is only one of the many proposals, and inflationary cosmology does not apply during say radiation dominated period. In Lubos's own blog a string gas cosmology was discussed as a guest post and this cosmology is certainly not inflationary cosmology! By the way, in TGD framework string gas is replaced with cosmic strings and there are many common elements between these views about cosmology.

  3. Both Sabine and Lubos talk about holography in quantum gravity sense: 2-D or 3-D holograms in 4-D space-time defined by black hole horizons. This holography is rather speculative notion and in principle something very different from AdS/CFT correspondence since in this case one would reduce 4-D physics to 3-D or even 2-D and in the case of Maldacena n-D physics would represented as part of n+1-D physics (Sn excitations are trivial).

It should be also made clear that the AdSn/CFT correspondence is application of the mathematics of string theory and not a part of string theory. In string theory S10-n replaced with Calabi-Yau space so that the relationship is far from obvious.

Various forms of holography principle

There are very many forms of holography principle with varying degree of mathematical and physical feasibility.

  1. t'Hooft proposed a holography principle relating gauge theory description to string model type description: for gauge theory in M4 the strings would live in M4 and intuitively correspond to planar Feynman diagrams forming net like structures.

  2. In general relativity it is natural to make the conjecture that 2-D black-hole horizon is hologram. It is often assumed - an ad hoc assumption is in question - that single bit corresponds to an area of Planck length squared so that horizon area would could carry only finite number of bits. Sabine talks about this form of holography. Also Lubos speaks about this holography instead of better established AdS5/CFT holography as he starts to put down Sabine.

  3. Maldacena introduced super-string inspired holographies using 10-D target space with decomposition AdSn× S10-n. I guess that in M-theory speculations this decomposition would be replaced with AdSm× S11-n. AdSm has m-1-D conformally compactified Minkowski space as boundary. For AdS5/CFT hologram the boundary would be 4-dimensional and correspond to conformal compactification of M4 appearing also in twistorial approach and being motivated by 4-D conformal symmetry. QFT in M4 would have higher-D stringy/gravitational description.

    Maldecena holography must be distinguished from the gravitational holography in which one conjectures that 4-D gravitation allows 3-D or even 2-D QFT type description in terms of black hole horizons. These are quite different holographies but for some reason neither Sabine nor Lubos do not emphasize this distinction.

I do not know how feasible all these conjectured AdSn/CFT correspondences really are.
  1. It is argued that one can think that S10-n excitations do not contribute to the physics in the scales much longer than S10-n size so that higher-D space effectively reduces to AdSn. Hence one would have hologram as n-1-dimensional representation for physics in n-dimensions rather than for 9-D physics in 10 dimensions.

  2. This is not not enough: if one wants gravitational holography in the sense suggested by blackhole physics and t'Hooft's original argument one should be able to replace AdSn× S10-n with 4-dimensional space-time of general relativity and in quantum gravity one should speak about quantum superpositions of space-time surfaces. One would have "quantum holography". Whether holography extends in this manner is far from obvious. AdS3 with 2-D with conformally compactified M2 as boundary would be analogous with this holography.

What about experimental side? AdS5× S5 holography have been applied in attempts to explain RHIC and later LHC results but with a rather modest success: even qualitative predictions are wrong as reported by Sabine in her earlier posting.

What looks strange to me that one is ready to introduce strings in 10-dimensional space to explain these findings in conflict with perturbative QCD but refuses to consider the possibility that a fractal copy of hadronic physics modellable using hadronic string like objects in 4-D space-time could explain the findings much more elegantly (see this)! But this is sociology of science which rational mind is not able to understand.

AdS/CFT holography has been applied also to nuclear physics and condensed matter without any breakthroughs. The description of atomic nuclei or condensed matter as blackholes in 10 dimensions has not led to any breakthroughs. Amusingly, in TGD framework atomic nuclei can be described as wounded string like objects in the familiar 4-D space-time but this is of course too science-fictive and speculative as compared to blackholes in 10 dimensions;-). Wikipedia article contains comments about these applications (see this).

Holography in TGD framework reduces to General Coordinate Invariance

In TGD framework holograms are effectively 2-D as they should be if quantum gravitational intuition is correct. The pair formed by AdS5 and its boundary which is 4-D Minkowski space M4 is replaced with 4-D space-time surface in M4× CP2 and its space-like boundaries or light-like "boundaries". The holography holds trued for single space-time surface in quantum superposition of them.

  1. Holography in TGD sense follows from General Coordinate Invariance (GCI) in TGD framework in which gravity becomes sub-manifold gravity. Single big principle instead of two means quite a dramatic increase in conceptual economy and was in ancient times seen as a signal that theory has been able to catch something very profound about reality.

  2. Also a stronger form of holography is possible. Suppose one requires that light-like "boundaries" identified as regions at which induced metric changes its signature from Minkowskian to Euclidian inside lines of generalized Feynman diagrams and space-like 3-surfaces at the ends of causal diamonds provide dual descriptions of quantum physics. If this is the case, one obtains strong form of GCI and consequently strong form of holography. The universe is effectively 2-dimensional: partonic 2-surfaces defined by intersections of these two kinds of 3-surfaces and tangent 4-D space - data at them would code for physics.

    It is amusing that strong form of holography is very nearly the same as the holography as we encounter it in everyday world and in sensory perception we see things as 2-dimensional! Note however that the representability of space-time as a 4-surface of M4× CP2 is essential.

"Effectively" is an important limitation.
  1. Quantum states contain information about actual 3-dimensionality. For instance, the integers characterizing the modes of induced spinor fields restricted at string world sheets code for this kind of information. These string world sheets accompanying magnetic flux tubes carrying monopole fluxes and connecting various partonic 2-surfaces are the counterparts of strings connecting points at the boundary of AdS5× S5 so that these two holographies have a lot of common. In TGD one might perhaps speak about dual descriptions provided by partonic 2-surfaces and string world sheets. The situation is not however completely clear.

  2. Zero energy ontology originally motivated by the failure of the strict determinism of Kähler action implies a hierarchy of causal diamonds (CDs) so that one obtains holography only in given UV and IR resolutions (considering single CD). Also Sabine emphasizes the importance of measurement resolution but formulates this in terms of finite area per bit condition. Discretization at space-time level is the number theoretic manner to express finite measurement resolution. Inclusions of hyper-finite factors of type II1 provide the mathematical language to express the notion of finite measurement resolution and leads to the emergence of quantum groups and quantum spinors.

  3. An additional complication is due to the fact that one does not have single space-time surface but quantum superposition of them. If quantum classical correspondence is taken really seriously, one is led to the conjecture that all space-time surface in allowed superpositions have the same classical n-point functions for coordinate invariant field like quantities as functions of M4 coordinates and that these n-point functions are identical with their quantal counterparts. This is very powerful constraint on quantum states and without further specifications could be too strong. "Modulo finite measurement resolution" is one such additional specification.

  4. The hierarchy of CDs implies that we are 3- (or 4-) dimensional in the same as a 3-D lattice consisting of 2-D (3-D) objects is 3-D (4-D). Although quantum states are coded by data assignable to partonic 2-surfaces at boundaries of CDs, the understanding of what happens in quantum measurements requires both quantum states and and their space-time correlates since every measurement outcome is formulated in terms of classical space-time physics. Quantum numbers such as momenta, spin, charge, etc.. label quantum states whereas in space-time description one has frequencies, field intensities, etc... Both are needed.

For these reasons and as a habitant of TGD Universe I cannot agree when someone says that we live in (2-D or 3-D) hologram/are hologram. Nature just represents same information in many manners just as computers provide a large number of different representations of the same data. This does not diminish the mathematical power of strong form of GCI/holography.