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Yershov's Preon Theory & Bilson-Thompson & LQG & mass prediction

  1. Sep 10, 2006 #1
    it's my understanding that Yershov's Preon Theory can predict particle masses a priori and his paper also describes second and third generation particles, whereas Bilson-Thompson only the first generation.
    http://arxiv.org/abs/physics/0301034
    http://arxiv.org/abs/hep-ph/0207132

    Is it compatible or derivable from Bilson-Thompson's theory, http://arxiv.org/abs/hep-ph/0503213 which apparently can be derived from LQG spin networks.

    Yershov paper here http://arxiv.org/abs/physics/0207120 seems to make points of contact with Bilson-Thompson. Could Bilson-Thompson ribbon model make use of Yershov's Preon model to predict particle masses?

    Incidentally, John Baez or Lee Smolin will Bilson-Thompsonplan to publish papers mapping out the remainder of the SM? His paper were only for first generation.

    Has there been any there been any indications Bilson-Thompson might publish an article along with Yershov?

    What would be cool would be starting with spin networks, which give rise both to general relavitivity and the standard model, you can map out the entire standard model using preons and predict particle masses.

    "Yershov Properties of space can be used for explanation of some patterns of nature. For example, topology of space might be responsible for the enigmatic spectrum of masses of quarks and leptons, which so far has not been explained. Here we consider a topological structure discovered in 1882 by F.C.Klein and show that properties of this structure necessarily lead to formation of a set of secondary topological structures, number of which matches the number of known fundamental particles. Some features of these structures can be related to quantum numbers and masses of the particles"
     
  2. jcsd
  3. Sep 10, 2006 #2

    CarlB

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    I like the idea behind the paper. The neutrino masses he gives are incompatible with current measurements of the neutrino oscillations. But in 2002, they might have been reasonable.

    Converting his neutrino mass numbers into eV by multiplying by the weight of a proton = 938272310 eV, his numbers are:

    [tex]\begin{array}{rcl}
    \nu_e &=& 0.00447 eV\\
    \nu_\mu &=& 0.00798 eV\\
    \nu_\tau &=& 0.00903 eV
    \end{array}[/tex]

    The differences between these numbers squared (which is what is measured in neutrino oscillations) are:

    [tex]\begin{array}{rcl}
    \nu_\mu^2 - \nu_e^2 &=& 2.0 \times 10^{-5} eV^2\\
    \nu_\tau^2-\nu_\mu^2 &=& 1.8 \times 10^{-5} eV^2\\
    \nu_\tau^2-\nu_e^2 &=& 6.2 \times 10^{-5} eV^2
    \end{array}[/tex]

    Measured values for the differences are [tex]2.5\times 10^{-3} eV^2[/tex] and [tex]8.0\times 10^{-5} eV^2[/tex].

    Now this is subject to the assumption that his neutrinos, [tex]\nu_e, \nu_\mu, \nu_\tau[/tex] are the same as what people SHOULD call [tex]\nu_1, \nu_2, \nu_3[/tex]. By "should" I mean that the flavor neutrinos are not mass eigentates and so talking about their masses should be avoided. I think the whole subject would be better understood if people never talked about flavor neutrinos at all, but instead referred to those things as mixed states of the numbered neutrinos. This thing eventually made it onto the wikipedia for neutrino oscillations after I complained. See the discussion here:
    http://en.wikipedia.org/wiki/Talk:Neutrino_oscillation

    On the other hand, if what the author is talking about really are the flavor neutrinos (which are not mass eigenstates), then the experimental numbers may not exclude his figures. I'd have to go look up the latest mixing data to do the computation. Uh, that doesn't look really trivial as the experimental data restricts only two degrees of freedom.

    Also, here is a related, later article, by the same author:

    http://arxiv.org/abs/physics/0301034

    Carl
     
    Last edited: Sep 10, 2006
  4. Sep 10, 2006 #3
    well you'd think that since string theory has been worked on for over 30 years, by the best minds, string theory could give us predictions?

     
  5. Sep 14, 2006 #4
    From Vladimir Yershov

    Unfortunately Bilson-Tompson's and my models are not compatible.
    The reason is that they are based on incompatible first-principles.
    Bilson-Tompson's twisted ribbons are abstract entities, the origin
    of which is not explained. In contrast, the preons in my model are
    postulated to be the simplest possible objects with no properties,
    except those arising from the symmetries of the 3D space. These
    symmetries force preons to cohere in structures of different
    complexity.

    There is no need in inventing anything: the structures emerge
    automatically. They grow as strings of preons, eventually some of
    them closing in loops, which precludes their further growth.
    So these loops are more or less stable (in comparison with strings).
    Their behaviour is complicated: they oscillate, spin and interact
    with each other. Surprisingly, the variety of these stable species
    can straightforwardly be mapped to the variety of known
    elementary particles, which indicates that this model is on the
    right track.

    The only thing these two models have in common is that both of
    them consider matter particles as organised patterns of empty space.
    But this idea is not new: perhaps the first who proposed it was
    J.A.Wheeler in 1962.

    The incompatibility of these two models can be seen from yet
    another point of view: Bilson-Tompsons' model is based on quantum
    mechanical approach, whereas mine uses the principles of general
    relativity. Maybe you know that QM and GR are not compatible
    in principle. That is why loop quantum gravity does not help either:
    it is a QM-based theory and therefore it is in a blind alley, whereas
    the general-relativistic approach is already much more promising.
    Still there is a very long way before an acceptable relativistic
    description of the preon structures could be achieved. But there
    are some indications that GR is a primary theory, whereas QM
    is secondary. You can find some more information as to how quantum
    properties could emerge from the GR-based preon-loops in the paper:

    http://uk.arxiv.org/abs/physics/0603054

    Regards,

    Vladimir

    I want to thank bananan for his generous donation without which this post would not be possible.
     
  6. Sep 14, 2006 #5
    Dear Marcus, John Baez, Lee Smolin, & LQG community, would you like to help out Vladimir Yershov out? If you can embed his preon theory with Sundance-Thompson, his Preon theory gives rise to the entire standard model, gives an account of why there is only 3 generations, and predicts masses in agreement with observation. It may also predict particle half-times, and **if** you can embed his theory with Sundance-Bilson, all these achievements starting with spin foam models, which also give rise to gravity (i.e Rovelli)


    Vladimir Yershov expressed to me via email a desire and willingness to work with the respective LQG community.

    Of course, you can post my e-mail to the physics
    forums. I agree that the preon-models is a valid
    alternative to the string theory and they have to be
    discussed and taken seriously.

    >
    > Is your particle also able to predict half-lifes for
    > particles? I've studied string theory at some level,
    > but my textbook/instructor never mentioned string
    > "instability".

    I believe that by proper simulations it would be possible
    to compute the half-lives of different particles. The strings
    arising from an ensemble of preons must be extremely
    short-living species (much shorter than any known particle).
    However, when those strings close into loops they must
    become extremely stable. Then, when the simplest
    (shortest) loops combine and form strings of loops,
    these "second-order" strings will be unstable again
    and so forth. Theoretical calculations of their half-lives
    must be very difficult, virtually impossible. So, my plan
    is to use the computer power for calculating the decay times
    for the W-boson and neutron. I know how to do this but
    I'll probably need a few years to get something workable
    (there are a lot technical difficulties and, in addition,
    I am not a great expert in the field).

    >
    > I disagree with your statements about LQG, which is a
    > quantized form of general relativity, resulting in
    > wilson lines labelled by spin networks.
    >
    > " Bilson-Tompson's twisted ribbons are abstract
    > entities, the origin of which is not explained. "
    >
    > His followup article shows that those ribbons arise
    > naturally from spinfoam models of LQG. (see below). Do
    > you think you can embed your preon theory into a
    > spinfoam model? Spinfoams and LQG is supposed to give
    > rise to general relativity with quantum corrections.
    >
    >
    > Please review this http://arxiv.org/abs/hep-th/0603022
    >

    Many thanks for the reference. After having a quick
    look at this paper I can see that actually there are
    more things in common between my model and that
    by Bilson-Tompson/Markopoulou/Smolin.
    In their model the ribbons are embedded into
    a three-manifold, whereas in my model ribbon-like
    structures can only occur in a (3+1)-manifold
    (as a result of preon's dynamics).
    Maybe it would not be difficult to extend their model to
    a four-dimensional case? Perhaps they have already
    done this (I have to read their paper). However, still
    I see the main difference between these two frameworks:
    that is, LQG is trying to find a possibility of GR to emerge
    from QM (e.g., by decoherence), whereas I am trying to
    get exactly the opposite thing: the emergence of QM from
    GR (I do not know if somebody else is going this way).
    How could these two opposites be reconciled?
    - I don't know.


    Regards,

    Vladimir






    I want to thank bananan for his generous donation without which this post would not be possible.
     
  7. Sep 14, 2006 #6

    marcus

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    bananan, thanks for including me in the list of those to whom the forgoing was addressed! My role is purely that of an observer, unlike the others you mentioned. I am glad to know about the research you mentioned and have the pointers, but i cannot suggest any appropriate action. Hopefully others will have some ideas and/or will want to reply to Yershov.
     
  8. Sep 14, 2006 #7
    No problem Marcus. Have you had a chance to review either or both Yershov and Bilson's preon model paper? I'm not entirely clear how either model gets around The mass paradox problem for preons. Is it they are extended objects (much like strings) rather than point particles?

    How would you respond to some of Yershov's questions such as

    1 However, still I see the main difference between these two frameworks:
    that is, LQG is trying to find a possibility of GR to emerge
    from QM (e.g., by decoherence), whereas I am trying to
    get exactly the opposite thing: the emergence of QM from
    GR (I do not know if somebody else is going this way).
    How could these two opposites be reconciled?

    2-Many thanks for the reference. After having a quick
    look at this paper I can see that actually there are
    more things in common between my model and that
    by Bilson-Tompson/Markopoulou/Smolin.
    In their model the ribbons are embedded into
    a three-manifold, whereas in my model ribbon-like
    structures can only occur in a (3+1)-manifold
    (as a result of preon's dynamics).
    Maybe it would not be difficult to extend their model to
    a four-dimensional case?

    3-Unfortunately Bilson-Tompson's and my models are not compatible.
    The reason is that they are based on incompatible first-principles.
    Bilson-Tompson's twisted ribbons are abstract entities, the origin
    of which is not explained. In contrast, the preons in my model are
    postulated to be the simplest possible objects with no properties,
    except those arising from the symmetries of the 3D space. These
    symmetries force preons to cohere in structures of different
    complexity.

    I know you're an enthusiastic support of LQG, and LQG & preons could together become a TOE.
    thanks
     
    Last edited: Sep 14, 2006
  9. Sep 18, 2006 #8
    Hi,

    that is only a short message to tell you that you are not alone. We also try to extract QM from GR. For that purpose we use a structure on the 4-manifold which is always choosen trivially, the differential (or smooth) structure. But on 4-manifolds there is an infinite number of possibilities (in all other dimensions there is only a finite number).
    We had the first success with that approach: We are able to derive the operator algebra of the fermions. See our paper gr-qc/0511089.

    Now we using the same approach to derive the cosmological constant (gr-qc/0609004).

    Torsten
     
  10. Sep 18, 2006 #9
    Dear Dan,

    Thanks for the message!

    Yershov on his own model v.s Bilson

    Unfortunately something has happen
    to the indicated web-page (it does not work).
    Instead I had a closer look at
    Bilson-Thompson/Markopoulou/Smolin's paper
    Now I can see that I was wrong and you are
    right about LQG, which, indeed, is trying to get
    QM emerging from GR (sincerely, I was thinking
    the opposite). Of course, when you embed 2-surfaces
    (ribbon graphs) into a 3-space and map their
    states to a Hilbert space, it is a kind of transition
    from GR to QM.


    Of course I am still far from the understanding
    of this model. I can see the kinematics of preons
    but not dynamics. It is said in the paper that the
    dynamics is generated by the ribbon transformation moves.
    But it is not clear what might cause those moves?
    The whole idea looks pretty nice. If we assume that
    space is formed of ribbons on the sub-Planck scale then
    it is logical to think that these ribbons must be twisted
    and interwined, which could give rise to topological
    invariants. These can be identified with some quantum
    numbers like charge, handedness etc. But where the magnetic
    properties of particles come from?

    When invariant states are identified with elementary
    particles, this is regarded as the answer to the question
    as to the physical meaning of the braids and twists.

    But if you look at the cited Bilson-Thompson's paper,
    his question about the physical meaning of twisting and
    braiding is different. He asks: What physical process these
    twisting and braiding represent?

    My answer to this question would be: They are twisted
    and braided paths of the truly primitive particles from my model.
    Even some pictures from my paper look like 180-degree twisted
    ribbons, although in my model they are closed in loops - not the
    open ribbons like in Bilson-Thompson's graphs. Could this be
    a kind of link between Bilson-Thompson and my models?
    Difficult to say...

    Regards,

    Vladimir
     
    Last edited: Sep 18, 2006
  11. Sep 19, 2006 #10
    I must confess, I don't understand this preon model of Yershov. It seems that the force is just coming out of thin air. Equation 2.3 of hep-ph/0207132 looks very odd to me - what is the mechanism of transfering momentum between the preons to give this force? Is this supposed to be action at a distance?

    It is interesting because he seems to get almost the right masses. The neutrinos are wrong, and the top mass is a bit off, but the others are pretty good. Unfortunately I am not following how he derives the number of preons in a particle.

    Also, I don't understand what happened to the energy associated with the force. The mass of a bound state is really just the energy contained in it as seen in its rest frame - so what happened to the energy associated the force between the preons which supposedly hold them together. (Compare for example, the proton mass, which is not simply the sum of the constituant quark masses.)
     
  12. Sep 19, 2006 #11
    I agree, it's not clear to me how he decides how many preon units a particle has and how he assigns those masses.
     
  13. Sep 19, 2006 #12
    Hi,
    > Here's a paper by John Baez on LQG-Spin Foam models
    > which is a link and attached as PDF.
    >
    > http://math.ucr.edu/home/baez/spin_foam_models/spin_foam_models.pdf
    >
    > BT & the LQG community is attempting to embed preon
    > ribbon theory into spin foam models, so you get both
    > gravity and the standard model, without the extra
    > structures (i.e 11D, SUSY) of string theory.
    >
    >
    >
    > Enjoy

    Hi Dan,

    Thanks for the reference to J.Baez's paper,
    which is quite interesting but gives me some
    strange impression that LQG is not very
    consistent in its intention to derive QM from GR.
    In this paper space is represented as
    a superposition of quantum states of a network of
    discrete graphs. This is clearly not the GR->QM
    but rather a reverse approach. Perhaps my
    impression is wrong, but this is what one can
    get from this paper. Quantum triangulation seems
    to be postulated here as a primary entity,
    whereas space - as secondary. On the other hand,
    some other LQG-papers declare taking first,
    say, a Riemannian manifold and then quantise
    it.

    Regards,

    Vladimir

    --
     
  14. Sep 22, 2006 #13
    Vladimir & myself -- any volunteers in helping him with spin foam/LQG models? He prefers GR based approaches.

    Finally, I have found that the link to Soudance's
    talk was not working because the UK-based computers are
    somehow blocked from accessing this page. However,
    by using a proxy I have managed to get through
    and to watch the programme. Indeed, it is a good
    addendum to his paper. Thank you very much for the
    link.


    >
    > LQG is usually thought of as a quantization of GR's
    > field equations, which gives you spin networks, which
    > can be modified to give spin foam models. It is
    > claimed that certain coherent spin foam models can
    > 1- give classical spacetime and
    > 2- give coherent states that would form the basis of
    > BT's preon model.
    >
    > I've enclosed some technical articles. Do you think
    > you can embed your preon theory into the framework of
    > spinfoam/LQG? If so I'd like to see such an article :)
    > (Or perhaps build on Sundance/Smolin/Mark..)
    >

    From your today's comments I see that my wrong impression
    about the origin of LQG could come from some papers, which
    discuss only the transition from a quantum spin network
    to a classical spacetime (not the first step of quantisation
    of GR). The articles that you have sent me give much more
    clear picture. As for the possibility of embedding the preon
    theory into the LQG framework, I am thinking ...
    But I need time for reading the papers and getting use to it.
    So far, I am very far from understanding where could I find
    a merging point. But there is a good example
    of Bilson-Thompson, Smolin and Markopoulou.
    So, let's see...

    > Some of the other physicists who have looked at your
    > paper have questions on the order of
    > 1- how did you decide how many preon units a particle
    > has

    Going to your questions:

    1)
    Actually there is no need to decide the number of preon
    units in the structure of a particle: minimising
    the effective potential gives you the answer.
    Here one can draw a parallel with the crystal structure.
    Very popular and good examples exist in carbon
    nano-technology. Two simplest low energy forms of carbon
    are graphite (6 units closed in a 2D loop) and diamond
    (5 units closed in a 3D structure). Then you have spherically
    closed structures of fullerens with 60, 70 and 540 units,
    as well as carbon nanotubes, nanotoroids ets. In this
    way you get a discrete spectrum of species with
    a well-defined number of constituents.

    If you take colour-charged particles (preons in my model)
    and assume them to be attracted/repulsed from each other in
    accordance with the known pattern of attraction/repulsion
    for colour charges from QCD, then you will end up
    with a discrete spectrum of species with a well-defined number
    of constituents (preons). For like-charged preons you will
    get dipoles (2 units), tripoles (3 units) and triplets of
    tripoles (9 units). The colour-field of the latter is ring-closed,
    which makes this structure stable. Unlike carbon structures, the
    elements of the preon structures can spin around each other and
    move along their ring-closed trajectories, which complicates
    the situation because you have to take into account
    magnetic fields due to the motion of preons.

    If you want, you can get some more details
    from a description, which is now available on-line:

    http://uk.arxiv.org/abs/physics/0609185


    > 2- how did you decide how to put how much mass to each
    > unit of preon

    2)
    For simplicity I assigned unit mass to each preon.
    Then, for the simplest structures, to get their massed
    you can just sum up the number of preons in the
    structure if it is formed of like-charged preons.
    Of course, this is a first approximation, as for the
    accurate calculation of masses one has to take into
    account the preon motions, the residuals from their
    binding energies etc. When two unlike-charged preons
    combine, their fields would cancel each other, nullifying
    the mass of the system. There should remain a small
    residual field (mass), but on this stage it can be
    neglected. By noticing that charge and mass must
    be intimately related, I have suggested that when a neutral
    (almost massless) looped structure enclose a smaller
    charged structure/particle or if it is enclosed by a larger
    charged loop (that is, when the source of the field is
    inside of the neutral loop) all of its preon constituents
    would contribute to the mass of the combined structure.
    There are further complications when the structures
    oscillate with respect to each other. If the frequency
    (energy) of these oscillations is large, the mass of the
    combined structure would also be large (even if the
    oscillating components are almost massless).

    > 3- what you think preons are built on
    >

    3)
    I think of the preons as of topological features of space.
    For example, they can be viewed as microscopic black
    holes or something similar. LQG also regards particles
    as made of space features. This gives a possible link
    between these two models. The only problem with LQG
    is that it lacks dynamics.

    Regards,

    Vladimir
     
  15. Sep 23, 2006 #14
    Hi Dan,

    On Saturday 23 Sep 2006 02:51, you wrote:
    > Hello,
    > Do you think Bilson's idea of using ribbons with
    > twists be extended in your model? Akin to string
    > theory?

    Not only I think that Bilson's idea could be
    extended to my model, but that it is already there:
    inadvertently he has unravelled a structure, which
    corresponds to the dynamics of sub-quark entities
    from my model. At the beginning I saw the
    twisted current loops that were emerging in my
    model as a mere curiosity (but they were unavoidable).
    Later I found that these twists were extremely
    important for the way different composite particles
    interact with each other. Bilson's lucky guess
    was brilliant.

    > I am curious as to what you thought of the
    > merits of Sundance's talk as you and he are both
    > working on preon theory. Do you think you can extend
    > Bilson's theory to include spin and mass, and explain
    > 3 generations? Do you accept the higgs field/higgs
    > boson explanation of mass? There was a paper which
    > suggests preons could explain mass without the higgs
    > field/higgs boson. arxiv.org/abs/hep-ph/9709227
    >

    I like also his presentation, but when watching it
    I had some obtrusive feeling that something important
    was missing. Then I realised that particle magnetic
    properties were completely ignored. Is it possible
    building a theory of something and ignoring an
    important property of this something?
    That is why to my gusto Bilson's model (not his talk)
    was too much abstract. For instance, how could the
    electric field (particle charge) be explained by a
    twist or node of something? Maybe this is possible -
    I don't know - but this should somehow be explained
    in the first place, or at least a hint should be
    given.

    The extract from "New Scientist" you have cited
    shows that Sundance was indeed considering the possibility
    of preons being microscopic black- or wormholes.
    It looks like he took no notice of the branch I was
    exploring and arrived to a static model.
    But he was very close to my starting point.
    From this perspective, even closer to mine is
    string theory because strings are dynamic entities
    (they move and vibrate like the preon strings
    in my model).

    How to explain three particle generations? I think that,
    for the time being, in order to sweep a larger area and
    to have a wider diversity of possible models we better to
    explore both frameworks. I have already my framework
    extended towards some heavy nuclei (let alone the three
    generations).

    A few years ago I saw already the paper you are mentioning.
    I agree with the authors of this paper. Indeed, why should
    a preon model be concerned with the Higgs particle? The masses
    of composite entities could easily be explained without Higgs.
    Does anybody invoke Higgs to explain the proton's mass,
    which is now accepted to be a composite particle?
    Of course, not. The bulk of this mass is known to arise
    from the motions of its constituents - almost massless quarks
    and gluons. Similarly, once assuming the compositeness
    of elementary particles, the Higgs particle automatically
    becomes unnecessary.

    > Does your theory, or Bilsons for that matter, have a
    > problem with the mass paradox, that in such a small
    > region, the momentum of uncertainty would be large?
    >

    I don't know whether there is a problem with the mass
    paradox in Bilson's theory (perhaps he has not arrived
    to that point yet), but I feel comfortable not having
    this problem in my model. The momentum uncertainty is
    suppressed by preons' huge binding energies. I have
    mentioned this in the discussion section of the my paper
    http://uk.arxiv.org/abs/physics/0609185


    Regards,

    Vladimir
     
  16. Sep 26, 2006 #15
    Since a moderator asked,

    "From: "Vladimir Yershov" < k>
    To: "dan
    Subject: Re: Bilson-Thompson preon theory
    Date: Thu, 14 Sep 2006 14:58:18 +0100

    Dear Dan,

    Of course, you can post my e-mail to the physics
    forums. I agree that the preon-models is a valid
    alternative to the string theory and they have to be
    discussed and taken seriously.


    *******************************************************

    What followers are some emails. Anyone is invited to participate.
    If this violates forum rules I will promptly stop. Please notify me via PM or simply delete these postings and I will get the point. On another occassion Lubos Motl has given me his permission as well (string related) and this is on his weblog.

    I want to thank bananan for his generous donation.

    From: "Vladimir Yershov"
    Subject: Re: Bilson-Thompson preon theory
    Date: Tue, 26 Sep 2006 16:29:54 +0100


    Hi Dan,

    >
    > I thought BT was funny when he said "Greed is good".
    > Incidentally I see that your article was published
    > just a couple of days ago in arix.
    >

    I have published this paper a few days ago to give you
    some more details, which I couldn't give by e-mail.
    As for "Greed", I think that when you give a talk you are
    slightly acting, like in a movie. So, Sundance used a
    phrase from Oliver Stone's film. I would agree that greed
    for knowledge is certainly a good thing. The other types
    of greed might not be so good.

    >
    > By composite particles do you mean the particles of
    > the standard model? Presumably the whole preon project
    > is to reduce the SM to preons.
    >

    Yes, of course, I mean the standard model
    particles. Reducing the standard model to a fewer number
    of entities still leave you with the questions: Where
    these fewer number of entities come from? Why they are
    different from each other? The only logical solution to this
    problem would be reducing the standard model to a single
    entity ("the preon").

    > Can BT's results be
    > extended by your results, perhaps explaining the
    > second and third generation fermions, and possibly
    > particle mass-energies and even half-lives? (such
    > results would make a good addition to arix).
    >

    For the time being I do not see how to do that
    straightforwardly. When looking at the papers
    you have sent me (thanks for that), I can propose
    that by encoding in terms of graphs the fields
    postulated in my model one could, in principle,
    arrive to connections and constraints similar to those
    appearing in LQG spin network models. For instance,
    initial 3D preon configurations could be denoted by
    1D-graphs. Then when this system evolves in time
    we'll get 2D-graphs in a 4D-pseudospace -
    something similar to a spin network.

    There must be a lot of technical difficulties when
    building such a model. For example, to develop
    a theory of a preon-based electron we should take
    care of at least nine fields. I don't think this is possible
    non-perturbatively. But I don't see any objection
    as to why this programme couldn't be realised
    in principle. The pay-off should be great, e.g.,
    derivation from first principles of some fundamental
    constants of nature, unification of all the forces and,
    of course, reconciliation of GR with QM.
    Helical structures, like Bilson's ribbons, will arise
    and be explained automatically. Of course they
    shouldn't be necessarily the same as described
    in Bilson's paper, but some twisted structures are
    unavoidable because angular momentum has to go
    somewhere.

    By the way, the topological theory presented in
    Khovanov's paper (http://arxiv.org/abs/math.QA/0609335)
    hints where Bilson's inspiration came from: Khovanov's
    graphs are exactly the same as Bilson's, but, of course,
    Khovanov's theory is much more general and broader.

    >
    > If LHC or TEV does find a higgs boson, how would such
    > a result affect your preon model? It doesn't seem BT's
    > model maps out a higgs particle.
    >

    The higgs boson is absolutely necessary to explain the
    masses of the standard model particles, which are
    supposed to be point-like. So the possible discovery
    of higgs by LHC or TEV will be good for the standard
    model. But it will not affect preon models because
    their main goal is to explain why do we observe
    this specific set of particles and not something else.
    Within the framework of standard model there is no
    way of explaining the observed variety of species
    because this model was designed to solve other
    problems, not this one. The spectrum of particle
    species is a very strong observational evidence
    in favour of the compositeness of the standard
    model particles. The decay of heavy fundamental
    particles into lighter ones is yet another indication.
    Moreover, there are proposals that the higgs itself
    (although it has not yet been observed) could be
    a composite particle.


    Regards,

    Vladimir
     
    Last edited: Sep 26, 2006
  17. Sep 26, 2006 #16

    selfAdjoint

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    Dearly Missed

    And I thank you too, bananan, for carrying on and posting this very interesting discussion. The link to Khovanov's topological-categorical results was especially valuable to me, but the whole braid/preon area is looking valuable.

    Is anybody communicating the methods of the LQG researchers to Dr. Yershov? I mean things like getting the Hilbert spaces of volume and such and the algebras on them from the three dimensional networks, which can then be quantized using standard theorems?
     
  18. Sep 26, 2006 #17
    Hi,


    Yershov's background seems to be particle physics, and he does not seem to have much exposure to LQG research (he asked me pretty basic questions). So as far as I know, the answer is no, but he appreciates receiving any relevant papers on the subject. Do you have any I should offer? Which papers would involve "getting the Hilbert spaces of volume and such and the algebras on them from the three dimensional networks, which can then be quantized using standard theorems".

    Yershov, like Bilson initially, does not seem to embrace string theory, and seems to want to ground preons on wormholes or micro-black holes of classical GR (which seems doomed :)
     
    Last edited: Sep 26, 2006
  19. Sep 26, 2006 #18
    Hey bananan and others,

    In that case Yershov might be interested in the work of Mark Hadley, who proposes a general framework for the derivation of QM from GR, and has in particular pursued models of particles based on topological constructs like wormholes. He calls his particles geons, and his main point is that if you try to build a model out of 3 dimensions (like Wheeler did a long time ago), it will fail -- you need to start at the outset working with all 4 spacetime dimensions! To emphasize this point, he calls them 4-geons.

    Some of the concepts he deals with: he argues that there is no such thing as the Higgs; he proposes a classical model for spin; he discusses "charge without charge," ie how topology can give rise to charge; and whether the underlying quantum spacetimes (manifolds for Hadley, spin-foams for LQG) should or should not be time-orientable.

    Could any of his stuff carry over to preons? Dunno, maybe. Hope so!

    For example: maybe we should be thinking about "4-preon" models (might work?) versus "3-preon" models (doomed to failure?). hmmm..

    http://www2.warwick.ac.uk/fac/sci/physics/staff/academic/mhadley/

    David
     
  20. Sep 27, 2006 #19
    Since a moderator asked,

    "From: "Vladimir Yershov" < k>
    To: "dan
    Subject: Re: Bilson-Thompson preon theory
    Date: Thu, 14 Sep 2006 14:58:18 +0100

    Dear Dan,

    Of course, you can post my e-mail to the physics
    forums. I agree that the preon-models is a valid
    alternative to the string theory and they have to be
    discussed and taken seriously.


    ************************************************** *****

    What followers are some of my own personal emails. Anyone is invited to participate. The following is a cut and paste email, with my own permission and Vlad's permission. I do not know how to use PF's quoting but Yahoo mail makes it clear which is mine and which is Vlad's. ************************************************** *****

    Hi Dan,


    On Wednesday 27 Sep 2006 03:57, you wrote:
    > Hi Vlad,
    >
    > I think the way BT gets around the mass paradox is
    > that the mass paradox arises from a model of point
    > particles smaller than the elementary particles of the
    > SM, whereas he is proposing ribbon extended structures
    > that are bound together and not necessarily smaller
    > than the particles they compose. As a bound state they
    > interact as though they were point particles, but as a
    > three-ribbon they are not necessarily smaller than
    > that elementary point particles like quarks. They could be
    > the same size (in length) as a quark, for example.

    Maybe this is the case, but on this scale the momentum
    uncertainty is huge and there is a problem here even for
    extended particles unless you find a mechanism to suppress
    this energy.

    >
    > While grounding your preon model on LQG-spin foam
    > theory might be challenging, what about building on
    > BT's model (including chirality, spin, mass, etc.) in
    > the opposite direction, towards the SM, since you have
    > suggested he is close to your starting point?

    There is some visible analogy between the two models,
    but not everything is so simple. The combinatorial way
    of coupling ribbons in BT model works only for the
    simplest structures (say, first generation
    particles). In my model the first generation particles are
    not the simplest preon-structures but the simplest
    ring-closed structures (loops) formed of the preons.
    These loops can be further combined (using all the time
    the same basic fields) forming strings. When these strings
    (of loops) become long enough to close in "second-order"
    loops, they form a group of structures, which are
    quasi-stable (because they are loops) and which
    could be identified with the second family of the
    fermions, etc. This is quite different from Bilson's
    structure formation scheme, and I don't see yet
    how to reconcile the two schemes.

    By the way, I don't agree that my model starts
    with 3 different kinds of basic particles. Aren't
    different particles in QFT sometimes regarded
    as a single field with different flavours?
    Aren't the electron and positron regarded identical
    except for the electric field direction? Aren't the
    proton and neutron regarded as the same entity
    rotated in a phase space? Aren't quarks regarded
    keeping their identities when exchanging colours?
    Exactly in the same way the preons in my model
    are regarded as a single entity with different
    possible orientations of its field (or, if you like,
    a single entity rotated in a phase space).

    >
    > Your theory seems to have antiparticles that somehow
    > cancel out mass (negative energy?) whereas it does not
    > appear BT' has such antiparticles.
    > It's not clear to me BT can account for chirality.
    >
    > In Bilson's paper he referenced another speculative
    > paper relating charge with inertial mass.
    >

    Sorry, no negative energy is needed. The mass-defect
    (binding energy) is a very well-known and established
    phenomenon. There is nothing new and nothing speculative
    in it. The mass IS energy (Einstein?), the charge
    is energy, hence, the mass and charge are intimately
    related, isn't it?


    > Perhaps the twists in Bilson's ribbon model could
    > correspond to the number of "preons" in your model, so
    > your derived mass formula could somehow be imposed on
    > Bilson's? Personally i wonder if the most natural way
    > to extend Bilson's model to the second and third
    > generation would be bound states of additional preon
    > strands.
    >

    I don't think so. The number of preons in each structure
    of my model is determined by the combination of individual
    SU(3)/U(1)-symmetries of each preon in the structure.
    It is difficult to reduce such a complicated combination
    to a simple twist.

    >
    > So what research direction are you taking your preon
    > models? I forget but I take it your background is in
    > particle physics? It doesn't seem to me preon models
    > command much interest, playing second fiddle to
    > strings.
    >
    > > By the way, the topological theory presented in
    > > Khovanov's paper
    > > (http://arxiv.org/abs/math.QA/0609335)
    > > hints where Bilson's inspiration came from:
    > > Khovanov's
    > > graphs are exactly the same as Bilson's, but, of
    > > course,
    > > Khovanov's theory is much more general and broader.
    >
    > Except when you see the date of BT's paper, 2005, and
    > this paper, sept 2006, BT's paper precedes in time
    > Khovanov's paper. Khovanov might offer some ideas on
    > the dynamics of BT's preons, including particle energy
    > and transformation.
    >

    In this case the date of the publication does not matter.
    From Khovanov's paper it is clear that he was working
    on his theory since time ago. An, indeed, if you look at
    his references, you will see that exactly the same braided
    graphs as in Bilson's paper were already in Khovanov's
    in 2001 and 2002:
    ...
    http://uk.arxiv.org/abs/math.QA/0103190
    Mikhail Khovanov
    A functor-valued invariant of tangles
    ...
    http://uk.arxiv.org/abs/math.QA/0207264
    Mikhail Khovanov
    An invariant of tangle cobordisms
    ...

    Thanks for the link to the physicsforum. I have
    found there some interesting (and useful for me) comments
    about our e-mail exchange. For example, I appreciate
    the comment by "straycat" mentioning Mark Hadley's work.
    Indeed, this work is pretty much in line with mine, and Hadley's
    4-geons are very close to the preons from my model (both are
    topological features of a non-orientable manifold).

    Answering your question about my background, you will
    be disappointed - it is not at all particle physics - it's astronomy.
    I am just curious about particles and pursue them just for fun
    (am I wrong?). It is you who has drawn my attention to LQG.
    So far, I was not concerned with this direction ("nobody will
    embrace the unembraceable"). Now, learning some basics of it,
    I see that LQG has, indeed, relevance to what I am doing.
    Actually, there is a lot of information available for newcomers
    (your links to John Baez are especially good, and I have found
    some other useful links on this physicsforum web-page).
    Of course, I'll need time for finding a working
    relationship between LQG and my model. One of the
    possibilities could be the scheme you have mentioned
    here.

    I have noticed that in this forum you use a nick "bananan".
    I am just curious: does it have something to do with
    Sergey Bugayev's "malchik bananan"?

    Regards,

    Vladimir
    ********************
    I did not know Yeshov is an astronomer/astrophysicist. I assumed he was high-energy. HEP.

    Incidentally when I have the time I plan to put together LQC papers by Bojworld and Singn on loop quantum cosmology models, such as Sing resolution of the naked singularity, and Boworld's big-bounce and provide that to Yershov. If there are others feel free to let me know. It might be a good idea for someone to have basic topics (i.e particle physics, astrophysics, QFT, semiclassical issues) and fundamental papers in those topics (i.e I gave Yershov Baez' paper on spin foam which he greater appreciated).
     
  21. Sep 27, 2006 #20
    Good! I hope you will contact him. You and Mark are certainly welcome to discuss ideas (if you would like to do so publicly) in my yahoo! group, QM_from_GR -- Mark is one of the group members.

    http://groups.yahoo.com/group/QM_from_GR/

    David
     
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