The Strand Model of fundamental interactions

  1. The "Strand Model" of fundamental interactions

    [Mentor's note: This thread is a consolidation of three different threads which were started in our Beyond the Standard Model forum. They were moved to our former Independent Research forum, because in our view this represents a "new" or "personal" theory that has not yet reached mainstream physics discussion. At that time (2009) we allowed discussion of such theories only in the Independent Research forum. Since then we have closed the Independent Research forum and all discussions in it, as per this thread:

    https://www.physicsforums.com/showthread.php?t=506643

    and moved all posts from that forum into the General Physics forum. Note also our current rules, which can be found by clicking the Site Info --> Rules & Guidelines link at the top of any page here, in particular the section Discussion Guidelines. Please do not re-open discussion of this theory on Physics Forums until it has been published in a peer-reviewed journal.]

    [Original post by heinz:]

    The preprint http://arxiv.org/abs/0905.3905 by Schiller intrigues me. He proposes to deduce the electromagnetic, weak, and strong force from Planck units directly. So far, all microscopic models of nature I have ever read have a problem: there is no explanation of what interactions are. This case is different: interactions are defined as transfers of string crossings. From this idea, Schiller deduces an argument for why there are only three forces, and for why they have the usual gauge groups. It is the first time I ever read such an argument. That is why it intrigues me. On the other hand, the whole thing is really speculative. "There is no doubt your theory is crazy - the issue is: is it crazy enough?"
     
    Last edited by a moderator: May 17, 2013
  2. jcsd
  3. Re: Proposal for the origin of forces - is it crazy enough?

    *Maybe a premature comment but* I just skimmed the intro and the first paragraphs.

    I like the ambition to reconstruct the interactions somehow - this is something I expect as well!

    ...but since these strands seems to be just about as ad hoc as strings and branes in string theory and a little bit too realist inclined, and if I understand it right he assumes a background space, I think we need something even more crazy. I think it can be BOTH more crazy AND less speculative at the same time.

    I expect something long the line of interactions beeing defined and classified as various forms of interactions between information system, where the system complexity is an overall constraint limiting what interactions types that are distinguishable. Unification could be achievce the zero complexity limit. As complexity increases, forces distinguish themselves from each other, and the scaling process is an evolution, rather than some universal predictable mathematical transformation.

    ??

    /Fredrik
     
  4. Re: Proposal for the origin of forces - is it crazy enough?

    The model is based on a background because I do not think that a background-free theory is possible. It seems impossible to think or talk without using a background. So the model assumes a background to allow talking and thinking - even though the background is not observable. The background is a crutch for the formulation of the model.

    To put it in other terms: any observer introduces a background. This cannot be avoided.

    Christoph
     
  5. Re: Proposal for the origin of forces - is it crazy enough?

    Hello Christoph, thanks for your motivation!

    I have to say I fully agree with your argument here. This is subtle, and often causes confusion, but with my critic on background, I do not mean that there is never a background.

    I fully agree that the observers defines the background! but the observer is not static, the obsevers is evolving, and thus the background.

    So I don't object to the concept of background, I object to the introduction of observer independent and universal background.

    Now maybe I misunderstood you (like I noted I didn't get around to read all your paper yet!), if so I apologize.

    But IMO, the physical makeup of the observer might in general, put constraints on what background that is distinguishable, and in particular do I not see what the 3D or 4D space is distinguishable to an arbitrary observer.

    So I fully agree with that general notion that "the observer defines the background" but I insist that the observer is sujbect to evolution, and that difference observers might in general see different backgrounds.

    In particular does this contain also the model. In my view "the model" are constrained to physical observers. And thus it's not allowed (from my admittedly personal view) to anchor the model in an external fixed background. IE. the model is something that is alive and changing, not universal static truth.

    I got the impression that your background implicitly assumes some kind of "master observer" or birds view. If so, then the entire construction is in violation to the idea of an evolving observer, and thus evolving background.

    It's still possible I got you wrong. I'll try to skim the rest of hte paper later.

    /Fredrik
     
  6. Re: Proposal for the origin of forces - is it crazy enough?

    I agree completely. The observer introduces the background, and thus the background depends on the observer. Now, in flat space-time, the various backgrounds that are introduced by various (inertial) observers differ (only) by Lorentz boosts. Indeed, the model assumes that every observer has his own background. The observer-dependence of the background is in fact essential in the strand model: there is no "master observer".

    Christoph
     
  7. Re: Proposal for the origin of forces - is it crazy enough?

    Notat that what I meant to say here is for example in contrast to for example Rovellis view.

    Often background refers to spacetime metric etc. But I mean background as in ANY background information. Even in the narrow sense of GR, GR is also background dependent given the topology etc.

    The difference is taht some people form "background independent" models in a way that still relies on a more fundamental background structure. Alot of people think of this as mathematical structures that doesn't need physical basis. I don't like such views.

    Even physical law, is a kind of background. Because those who think that physical law are godlike hard constraints on the world, miss the point that we are talking about inside observers (humans) that have a view of this law, but there is no way to with certainty establish it 100% certain.

    That's my motivation for the evolutionary program, where physical law are not universal, it just happens to be the most invariant (although not PERFECTLY invariant) form of fundamental information about reality we have ; analogous to the DNA as the almost universal coding block for life (on earth at least).

    The variance in this DNA, or "physical law" is on such a long time scale due to inertia that it's variation is indistinguishable to a transient observer. And due to the inertia and interaction between systems, all similarly transient systems in the universe would effectively see the same law.

    But I stilll think there is a point when trying to reconstruct and unify physics, to acknowledge that (lke I think) the nature of law, is not universally static, but rather itself evolving.

    /Fredirk
     
  8. Re: Proposal for the origin of forces - is it crazy enough?

    I'll try to read a little longer in your paper later! maybe my comments was premature.

    /FRedrik
     
  9. MTd2

    MTd2 1,992
    Gold Member

    Re: Proposal for the origin of forces - is it crazy enough?

    I had a quick read on this paper when it was first uploaded, I would quote it on this thread about defining QFT on LQG,
    https://www.physicsforums.com/showthread.php?t=316697
    , that is, that strands working as topological obstructions between nodes of a spin network and generating. But Marcus convinced me that it was not necessary... but who knows? What do you think Schiler?

    BTW, what caused your paper to be sent to general physics and not to hep-th? Did you submit directly to there? I don't think it was bad at all.
     
  10. Re: Proposal for the origin of forces - is it crazy enough?

    To quote Lubos Motl, who was discussing that surfer dude nonsense from last year, we have:

    It is so sad that people buy into papers like this, if you are going to trade your life for a fantasy then why not play videogames, watch movies, or read literature?
     
  11. MTd2

    MTd2 1,992
    Gold Member

    Re: Proposal for the origin of forces - is it crazy enough?

    Garrett paper is on hep-th and it is not unusual for papers to be upgrade from gen-ph to hep-th.
     
  12. Re: Proposal for the origin of forces - is it crazy enough?

    In the proposed strand model, there are no nodes at all, since all strands are simple curves that go to spatial infinity at both ends. (Strands have no branches.) Particles are tangles of strands, and these tangles are found to follow the Dirac equation.The same deduction of the Dirac equation could maybe also be used for a web with nodes, but I am not sure. The lack of nodes simplifies the model, and allows a simple relation with hbar and c; I do not know whether this is possible also with webs that have nodes.

    Christoph Schiller
     
    Last edited: Jun 5, 2009
  13. MTd2

    MTd2 1,992
    Gold Member

    Re: Proposal for the origin of forces - is it crazy enough?

    So, how are the coordinates defined?
     
  14. Re: Proposal for the origin of forces - is it crazy enough?

    The strand model defines all observables in terms of Planck units. Coordinates are lengths; they are multiples of Planck lengths. The Planck length is defined through a crossing change. In short, the distance between two simultaneous events is the maximum number of crossing changes that fits in the space between the two simultaneous events.

    Christoph Schiller
     
  15. Re: Proposal for the origin of forces - is it crazy enough?

    Christoph, how can this be realized for electric fields? For gluon fields?
     
  16. Re: Proposal for the origin of forces - is it crazy enough?

    Christoph, am I right in thinking that you see these declared unobservable strands, as an underlying unobservable reality, that exists in a realist sense? A kind of hidden microstructure of reality, who explains observations?

    Is that correct?

    /Fredrik
     
  17. Re: Proposal for the origin of forces - is it crazy enough?

    The nature of a field is defined by the tangles that make it up. Electric fields are flows of photons, i.e. of specific tangles, and gluon fields are flows of gluons, i.e. of different tangles. Field intensity is then the number of these tangles.

    And above all remains the idea that strands are not observable, but only their crossing switches. This reproduces the quantum Lagrangians of each field.

    The appeal of the strand model is that these simple ideas allow to deduce the gauge groups of the electromagnetic, weak and strong nuclear forces - and no other.

    Christoph Schiller
     
    Last edited: Jun 7, 2009
  18. Re: Proposal for the origin of forces - is it crazy enough?

    Yes, strands are the common constituents of particles and vacuum and thus form their microstructure. Strands are featureless, fluctuating, impenetrable. Yes, strands are unobservable; only their crossing switches are observable, and all masurements, of any observable, are specific ways to count crossing switches. Crossing switches define all Planck units.

    Christoph Schiller
     
  19. Re: Proposal for the origin of forces - is it crazy enough?

    Before progressing into what this idea may predict, I think the justification of the starting point is essential. I don't find that confidence.

    It seems you compare to other microstructures, such as strings branes, and since your strands have less physical features, you rate it as less speculative, and can motivate it by occams razor.

    Beyond that, what are the other physical motivation do you have for your abstractions?
    It seems to me your motivation comes from analogies from knot theory and current physics.

    Do you have another more first principle reason that would make you have preference for this strand model?

    Also I'm not sure how you can call it featureless, it lacks the ordinary physical stuff like mass tension, but the whole abstraction of knots and strands in an embedded space still contains information right? To me featureless would mean "informationless", and the context of the strands may contain information.

    Even if I don't personally understand your strategy, I'm still curious to see if you can come up with unique predictions of the standard model parameters!

    /Fredrik
     
  20. Re: Proposal for the origin of forces - is it crazy enough?

    Yes, because the number of assumptions is quite small.

    The fundamental constituents must be able to describe both vacuum and particles. The fundamental constituents must be extended, to reproduce the entropy of black holes and the belt trick, i.e. spin 1/2. And they must be fluctuating, to reproduce homogeneity and isotropy. Given these conditions, featureless strands are simply the simplest option.


    The strands are featureless in the sense that they have no attached fields, quantum numbers, etc.

    The observable information contained in strands is the same as that contained in a wave function. So one can call strands a simple visualization of wave functions.


    The strategy is straightforward: deduce the three gauge groups, then the coupling constants, the masses, and the mixing angles.

    Christoph Schiller
     
    Last edited: Jun 7, 2009
  21. Re: Proposal for the origin of forces - is it crazy enough?

    Christoph, how definitive is your deduction of the three interactions? Do you see it as really settling the issue of the origin of the forces?
     
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