Talk:Preon

Explanation of (partial) cleanup
1) Yershov's research removed: The large amount of text dedicated to Yershov's work was inappropriate.  The works mentioned appear to have only been cited once (not including his citations of himself).  His work is highly speculative (to put it nicely) and should not appear in an encyclopedic setting.

2) Bilson-Thompson models removed: I removed all references to these models for the same reasons as Yershov's models. The Bilson-Thompson models are on a better standing than Yershov's models, but are also very recent and speculative.  The term preon is also used in a very broad sense in their discussion.

3) References to string theory removed: The discussions of string theory as a preon model were bizarre and ill-informed with many strange references to Lubos Motl.  String theory as a fundamental theory of nature is concerned with the UV completion of low energy effective field theories and does not relate directly any specific model of leptons, quarks etc. as composits.  Criticisms of string theory have their place, but not in a discussion of preons.  It is also false to claim that the waxing and waning of string theory's popularity in the physics community has had any effect on the popularity of preon models.  There has been an enormous increase in the interest in model building with the coming turn-on of LHC, but no corresponding increase in the popularity of preons.  Finally, the comparison between the number of articles on spires about preons and the number of articles about strings was childish and has been deleted.

Comments: This article is in serious need of expert attention.  The discussions of the relevant physics are very rough. Composite/preon theories have a sizable literature. They may not be as studied as other approaches, such as grand unification, however, there have been serious papers on the subject and a physicist who has worked in the field is required.

--Iellwood (talk) 18:26, 2 June 2008 (UTC)


 * For reference, this refers to the edit on 29 May 2008. Jimw338 (talk) 18:19, 27 December 2017 (UTC)

Simplify
I think this article has too much stuff about the Standard Model in it. The other article can be consulted for the details. The Background section can/should probably be cut down to a third of its present size, or less. - dcljr (talk) 04:07, 20 July 2005 (UTC)

Higgs
Also the standard model section may need to be updated soon to take account of the Higgs discovery. — Preceding unsigned comment added by 130.246.132.178 (talk) 14:46, 29 April 2013 (UTC)

Ohwilleke 00:39, 30 July 2005 (UTC) I didn't cut that much, but I did do a significant edit to trim it down. Yershov's Preon Theory & Bilson-Thompson & LQG & mass prediction

"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"

Ohwilleke would you mind donating your summary of yershov's model on your blog to wiki?

Cleanup and improve grammar
This page has been edited a lot recently. Overall the changes are an improvement, but whoever's doing it can you please try to make the changes cleaner and better-written? There are a lot of instances where the same thing is said repeatedly when once would do. I'm happy to do some cleaning-up, but it'd be good to have some help, and it'd be even better if the need for cleaning up was kept to a minimum in the first place. As a starting point the page can be shortened by combining some of the points on the list of motivations for studying preon models (e.g. 'Some supposedly fundamental particles are unstable' and '2nd and 3rd generation fermions decay' should be one bullet-point in a list, not two. Kickaha 21:24, 7 November 2006 (UTC)


 * Another thing-to-do. Shorten the last paragraph of section 2, below the list of considerations. It should be in an article about problems with string theory. We don't need most of that stuff in this article. Kickaha 23:31, 9 November 2006 (UTC)


 * Fix ambiguity. "The 2003 papers by Yershov [5] [6] are notable for being some of the only papers in the field" - which is it? Are they the only two papers, or are they some of few? "Some of the only" does not express something sensible.

Organization Issues
This article is pretty long, and a large part of it is devoted to explaining the Yershov and Bilson-Thompson models. If we are going to have long descriptions of specific preon models, rishons and some others deserve at least as much space as Yershov's version (which I've never heard of) and Bilson-Thompson's model (which isn't even really a preon theory).

But I don't think we want such long descriptions here. It would be much better to have short (one-paragraph) summaries of each important model (including the rishon and Fredrickson models, which currently don't even get a one-sentence description).

Significant models should be split off into their own articles (as with rishon). An article on Bilson-Thompson theory could discuss its connection to LQG, string net condensation, and M-theory in as much depth as its connection to prion theory. But these sections could be improved even without more information, just by organizing them into sectioned articles rather than trying to explain the whole theory in one long section.

Much of the information in the Bilson-Thompson section does actually belong in this article, but in separate sections. The spin foam, Wilson loop, and string net condensation theories are related to prion models in general, not specifically to Bilson-Thompson's model. (Of course because his is the only model that seems to be getting much theoretical attention, the distinction isn't always obvious from a casual glance.)

Also, it's a bit odd to refer to the same model as "Bilson-Thompson" in some sections and "Sundance" in others. I think I may have seen Lee Smolin referring to "sundance prions," but without any citation for that, given that Bilson-Thompson hasn't given his model a unique name, the normal procedure would be to refer to it by his last name, not his first.

Finally, the article is a bit repetitive in its slamming of string theory (which is pretty funny, considering that it ultimately seems to be very pro Bilson-Thompson, and last I heard he was looking at how to derive his prions from M-theory braneworld topology). It's worth explaining why the failure of string theory has led to interest in alternative foundation approaches, but it's not worth explaining more than once. --76.200.100.179 02:08, 3 June 2007 (UTC)

1948-1930 ≠ 30
In the "Preons in popular culture" section, it is apparently said that there has been thirty years of development between 1930 and 1948. Does anyone know which of the numbers are in error? Drhex 12:25, 31 July 2007 (UTC)

I've corrected "thirty" -> "eighteen" as most references seem to corroborate 1930 and 1948 as correct editions: 1930 by Amazing Stories: http://en.wikipedia.org/wiki/E._E._Smith 1948 by Fantasy Press: http://en.wikipedia.org/wiki/Fantasy_Press Alefu 22:07, 15 January 2008 (UTC)

Mass paradox
I feel there is a problem in the desciption of the mass paradox : the uncertainty principle, put in that way, tells us about the uncertainty in momentum, but it does not tell about the mass-energy. Momentum and energy are not the same thing, even if the units to describe them both are written "GeV". Usually this issue is described in terms of "compositeness scale" (Lambda), which has energy units. The compositeness scale is the scale of preon binding. There are experiments that indicate that the compositeness scale is larger than 1 TeV (for this number, one may refer to the PDG tables). To my understanding, there is a mass paradox only if we suppose that the second and third generations are excited states of the first one, since the differences in binding energies should be of the same order of magnitude as the compositeness scale, which is not the case for many of the observed masses. Philipum (talk) 08:41, 23 December 2008 (UTC)

OK I think I see : E² = p² + m², thus the energy is always greater than the momentum, and this is implicit in the reasoning. Perhaps it should be written in a more precise manner, though. Philipum (talk) 08:47, 23 December 2008 (UTC)


 * Couldn't the mass paradox be explained away by saying that preons experience a different (lower) value of h (Planck's constant), in much the same way that superbradyons have been proposed as experiencing a different (higher) value for c? If h was much smaller for preons than it is for particles composed of them, than they would have less momentum uncertainty and it would be possible for preons to have much smaller masses than the TeV scale, and therefore the binding interaction wouldn't have to be so high. Just a thought. Stonemason89 (talk) 21:54, 27 September 2009 (UTC)

I'm not going to put this in the main article because it's original thought and personally sourced, but the "mass paradox" assumes that preons are quantum-mechanical, which is to say that quantum mechanics is fundamental at the lowest possible conceptual level, which is a priori buying into a non-realist conception. There's no problem at all if quantum mechanics emerges as a result of interactions among preons (much as it emerges from interactions among particles and their pilot waves in de Broglie / Bohm theory). Heisenberg himself believed in a form of preon theory (source: Q & A after a talk at M.I.T. in 1972).Emvan (talk) 11:00, 31 March 2011 (UTC)

Modern state of the problem is missing
After the section "History" describing the historical backround of about 20-30 years ago it would be logical to describe to modern state of the problem rather than passing directly to the concluding sections.128.40.71.180 (talk) 18:48, 3 April 2009 (UTC)


 * And since the Higgs boson had been discovered, most of these preon theories became falsified. 84.25.143.80 (talk) 19:37, 13 July 2012 (UTC)

The Causal Link of Causal Set Theory as a Preon
Causal Set Theory has only two primitives at the basis of its constructions, "elements" and "causal links." The elements serve as bare individual locations, and the causal links connect these locations together to form causal sets. The primitives of the theory are used to construct space-time. When basic particles of the Standard Model are also constructed from causal links, the causal link is serving as a preon. Complexes built from causal links have inherent relative frequencies, suggesting that such frequency ratios are in fact energy ratios, in accord with Planck's E=hf. This would identify the causal link as the quantum of action. Thus, the preon construction of a particle from causal links yields an arrangement of quanta that can explain the relative mass-energy of that particle. Motivated by Russell and Whitehead's views on space-time as causal/temporal structure, I've carried out the construction of electrons and electron-neutrinos, protons and neutrons, together with a 4-D time lattice to serve as a discrete space-time manifold. Of the eight bullet-points in the Wiki article that list the challenges for a preon theory to meet, five are covered explicitly. These include the reduction of numerous particles to causal links, the definitions of mass, charge and color-charge, the mass values and oscillations of neutrino formations, and the candidate for dark matter. Gravity is also derived. The constructions are posted here:

"Causal Set Theory and the Origin of Mass-ratio" Quantum theory is reconstructed using standalone causal sets. The frequency ratios inherent in causal sets are used to define energy-ratios, implicating the causal link as the quantum of action. Space-time and its particle-like sequences are then constructed from causal links. A 4-D time-lattice pattern is defined and used to model neutrinos and electron clouds, which together constitute our 4-D manifold. A 6-D time-lattice is used to model the nucleons. The integration of the nucleus with its electron cloud allows calculation of the mass-ratio of the proton (or the neutron) with respect to the electron. Arrow diagrams, along with several ball-and-stick models, are used to streamline the presentation. http://vixra.org/pdf/1006.0070v1.pdf

-- Carey R. Carlson 71.210.179.215 (talk) 19:55, 27 October 2010 (UTC)

What do particle physicists actually observe?
The article says, " physicists observed hundreds of different kinds of particles in particle accelerators. " Do they really observe particles? Or do they infer particles as explanations of instrument readings? Should that sentence be corrected?(EnochBethany (talk) 18:03, 25 December 2014 (UTC))

How Can You Prove a Negative?
The article says, "no direct experimental evidence for lepton and quark compositeness has been found." How does the article writer know that passive statement is true? At the very moment of writing someone in Outer Mongolia may have just found direct experimental evidence. How do you know he has not? Why not revise the statement to, "The author of my hopefully reliable secondary source is ignorant of direct evidence, though it cannot be ruled out without being omnipresent in the world and being omniscient as to all experiments ever conducted." (EnochBethany (talk) 18:08, 25 December 2014 (UTC))


 * It would be sensational news. Would travel rapidly round the world, if the experiment was good enough to be plausible.  This happened with the (mistaken) claim that neutrinos were travelling faster than light.--GwydionM (talk) 17:53, 26 December 2014 (UTC)

What preons are particles made of?
I think it doesn't tell us what the types of preons actually do and what preons are in fermions and bosons. NegativelyChargedPositron (talk) 17:31, 13 December 2023 (UTC)

Finite size
Don't we already know the size of leptons and quarks isn't infinite? It's definitely finite, then. 174.103.211.189 (talk) 21:50, 12 January 2024 (UTC)