User talk:Marc Goossens

On refs and citations
Harvard style in-line citations are much more readable than footnotes, but seem to lack the reverse link (from ref or note to cite in the text). Or is there a way to get the best of both worlds?

As an alternative, can I make the combination of Citing_sources work with the structured citation templates?

Thanks! --Marc Goossens (talk) 13:47, 21 December 2007 (UTC)


 * There should be a little blue, upwards pointing arrow on the left side of each citation --Phoenix-wiki talk · contribs 20:04, 21 December 2007 (UTC)

. To complete the process, your preference will automatically be changed to  in the next few days. This does not require any intervention on your part and you will still be able to manually mark your edits as being 'minor'. The only thing that's changed is that you will no longer have them marked as minor by default.

For established users such as yourself there is a workaround available involving custom JavaScript. If you are familiar with the contents of WP:MINOR, and believe that it is still beneficial to the encyclopedia to have all your edits marked as such by default, then this discussion will give you the details you need to continue with this functionality indefinitely. If you have any problems, feel free to drop me a note.

Thank you for your understanding and happy editing :) Editing on behalf of User:Jarry1250, LivingBot (talk) 19:35, 14 March 2011 (UTC)

Avoiding Cite error in nested reference
See my draft contribution User:Marc Goossens/Schröter-Schelb Spacetime

I want to substantiate the claim made in Note 3 by adding a (nested) reference. The reference is correctly numbered and shown but throws a Cite error. How can this be avoided? I've seen there are bugs related to nested tags. Is there no way around?

TIA for any help and suggestions.

Marc Goossens (talk) 19:02, 1 May 2011 (UTC)
 * Ok, I think I have fixed the page to do what you want it to. I don't fully understand why moving the note, complete with your ref syntax, to be in text, rather then defined in the note section helped, but it appears to have. Some members of the en-help channel on IRC were able to point out a page where it was working, and that's how the page was constructed. Anyway, let me know if that is not what you were going for, and good luck with your editing. Monty  845  22:56, 1 May 2011 (UTC)

Reasoning about Space-Time
Hi Marc, I've just seen you large list of personal articles on Space-Time. I'll need some time though to run through all of it, yet what I've seen was already extremely helpful. It appears as if we have similar interest, though I'm using a BLOG for my stuff (where I try to find answers ...). If you like, just drop by: in BLOG: http://petri-grt.blogspot.com/ in FB: https://www.facebook.com/groups/275557099147507/ Yours Corneli{o}[us] --Corneliusni (talk) 18:49, 15 January 2012 (UTC)

Hilbert's Sixth problem: very focussed view
Hilbert's Sixth problem need not be seen as the search for the theory of everything *if* future developments in Physics do not throw up new axiomatic difficulties. I believe that they will not, and that therefore Hilbert's Sixth problem is solved and opens up new topics of great mathematical interest.

Previous Work
The bulk of the work was done by Darwin and Fowler who were, as Khintchine acknowledges, the first to present a logically clear version of Classical Statistical Mechanics in its relation to Classical Mechanics. They also treated the Quantum Case, and Schroedinger later showed that their Bohr-style treatment in terms of energy levels could be extended without any difficulty to the Heisenberg-Schroedinger style of Quantum Mechanics.

Quantum MEchanics was axiomatised by Weyl (with the help of Schroedinger and Debye) and, independently, Dirac. The main point is the selection of axioms and the formulation of definitions. However, Wigner pointed out, and taught von Neumann to see this, that these axioms were very unsatisfactory because of what Wigner called their «duality», i.e., the interaction of a particle with a measuring apparatus falls under the axioms in two very different ways: as a joint system, there is a joint wavefunction and the result is an entangled system with a deterministic, unitary evolution. But when treated as a Quantum system interacting with a logically ill-defined (because it is a primitive notion in Weyl and Dirac) «measurement apparatus», it is not entangled and it is a stochastic process.

I do not believe that Quantum Field Theory introduces any fundamental difficulties compared to this one, so I believe that fixing the problem Wigner analysed---later perspicuously analysed by John Bell---is the only remaining part of HIlbert's Sixth problem.

Khintchine unfairly ran-down the achievment of Darwin and Fowler by making unjustified, subjective, criticisms of their proofs which, althouth he conceded they were valid, he claimed they lacked perspicuity. I wonder if this was a kind of Stalinism, or a kind of normal competitive urge to puff up one's own contribution: Khintchine showed that the propositions of Darwin and Fowler were naturally probabiistic in nature and could be proved by means of a refinement of the usual limit theorems in probability theory. But from the standpoint of Hilbert, what is hard is not the proofs, it is the selection of the concepts, the selection of the axioms, and the formulation of definitions which is hard. Even physicists know what a proof is, but they rarely know what a definition is (Lucien Hardy, Dirac, Goldstone, Allahverdyan et al. absolutely are clueless in this respect.) John Bell did, as did Wigner.

Khintchine made a very great contribution to the subject by conjecturing that the real content of Statistical Mechanics could be proved in general for any system with sufficiently many degrees n of freedom (and the same, or only a few, «types» of components, weakly coupled): the observables of physical interest would behave as if they were ergodic, even though the system was nowhere near ergodic. Khintchine died in prison before he could make much progress, and I wonder if this is why he could not found a school to follow up his ideas. Ruelle and Lanford III made a little progress, but not much. This visionary conjecture is worth more than all of his theorems, in my opinion, and his theorems are worth a great deal indeed. Even engineers learn his theorems... you know, the one where he unfairly ran down Wiener's previous work on the subject by failing to provide a reference to Wiener at all....

It has not been realised that Khintchine's conjectures are the key to resolving Wigner's difficulty. One reason for this is that it has not been realised that getting a clear-cut definition of «probability» within an axiomatic system of Physics would be key for this problem. That such a definition was lacking was widely realised by mathematicians, such as Littlewood and Kolmogoroff, but that its solution would be relevant to Wigner's analysis was a surprise to me, although in hindsight it should not have been.

Prof. Jan von Plato of Helsinki University was the first to achieve a clearcut definition of «physical probability» but only in the special case of a classical mechanical, i.e., deterministic, ergodic system. Now, very few systems are known to be ergodic, and especially Quantum systems are linear and so are very far from being ergodic. So he could not see how to extend his results to the Quantum case.

The definition of probability
Although I had a quantum example, (published in Quantum Theory and Symmetries III, Cincinnati 2003, Argyres et al. eds., see http://www.worldscientific.com/doi/abs/10.1142/9789812702340_0017?prevSearch=Johnson+Entanglement&searchHistoryKey=, also http://arxiv.org/abs/quant-ph/0507017 , I could not formulate a general definition until recently. After proving Khintchine's conjectures for a new, and very wide, class of systems: all linear systems---I finally saw how to formulate a general definition.

My paper, « Descriptive Statistics as a new foundation for probability theory: part of Hilbert's Sixth Problem » was just accepted for publication in the Revista Investigaciones Operacionales (run by the statistics and OR dept. at Havana Univ.).

Although the paper and title are more modest, in my opinion this is the only part of Hilbert's Sixth problem that remained to be solved, so there it is. It turns out that probability is not a new primitive concept, neither is *measuring apparatus*, both can be defined in terms of other more fundamental concepts of Physics. Wave function, state, system, space, time, energy, are primitive. The measurement axioms are only approximations, and the concept of probability only becomes exactly applicable in the limit of an infinite number of degrees of freedom and Planck's constant's vanishing, but one can say exactly how good the approximation is, in terms of physically measureable quantities, for any finite value of n and h, which answers Littlewood's complaints about the usual frequency theory. Defining a new kind of thermodynamic limit answers Littlewood's challenge «... either you mean the ordinary limit, or you else you have the problem of explaining how ″limit″ behaves... You do not make an illegitimate conception legitimate by putting it into inverted commas.»