Template talk:Quantum field theory
|WikiProject Physics||(Rated Template-class)|
Merge with Quantum mechanics template
- I disagree, this will mess up the QM template with topics too advanced for an undergraduate student.(Sheliak (talk) 06:40, 3 March 2008 (UTC))
- Is wikipedia's audience just undergraduates, or everybody? --188.8.131.52 (talk) 06:15, 18 March 2008 (UTC)
- Everybody, but Sheliak's point still stands. --Michael C. Price talk 09:56, 18 March 2008 (UTC)
- I agree, though I'm a little uneasy about the content and organization of this template. Quantum field theories are used ubiquitously in solid state physics and in high energy physics, so I feel it would be proper to include models such as the Hubbard model and Ginzburg-Landau theory, etc. into the template. As far as the organization is concerned, it looks like the Standard model gets its own category when in fact, it is merely an elaborate example of quantum field theory. Perhaps the organization should be along the lines of (1) Theories in Solid State Physics (2) Theories in High energy Physics. I even recall seeing quantum field theories used in polymer physics, and in economics to model the stock market. So before I go ahead and perform a cosmetic surgery to this template, are there any comments? TriTertButoxy (talk) 22:16, 27 March 2008 (UTC)
Thanks for your contributions Truthnlove, for consistency I'll change the spelling of the Topics&Items to first capitalize letter and also remove the forenames of the scientists.
QFT Has Many Periods
- The founding period, where the theory was constructed by: Bohr-Rosenfeld/Born/Heisenberg/Dirac/Jordan/Klein. They recognized the need for field quantization. Heisenberg and others quantize scalar fields.
- The early field era: Klein, notes the paradoxes in the single-particle Dirac equation, Dirac-- who correctly quantizes the EM field and Fermi, Pauli, Stuckelberg. then there is the canonical anticommutator surprise by Fermi and Jordan. Fermis four-fermion interaction.
- The confusion era, when Heisenberg and others try to do perturbation theory and fail because of divergences. In this period, Majorana discovers a new fermion type and constructs an infinite component field for the first time, Wigner classifies all field equations, and interprets particles as irreps of the Poincare group. Pauli and Fierz find all wave equations and do spin-statistics theorem. Wigner recognizes the superselection sectors. Bethe does the Bethe ansatz.
- The renormalization era, the modern formulation, by Stuckelberg, Feynman, Schwinger, Tomonaga, Dyson etc. Bethe calculates lamb-shift. Dyson finds heuristics for renormalization.
- The 1950s. Lee model. Yang calculates the correlation functions of the Ising model. Lee Yang zeros. Renormalization is shown to hold to all orders following Ward, Bogoliubov, and others. Zimmermann formulates the forest formula at some point. There's a bunch of dispersion relations which probably warrant their own box.
- The 1960s. The connection to statistical models is becoming clearer, but not yet completely clear. Extended structures are analyzed by Skyrme then others for the first time-- fermions from bosonic theories. Schwinger shows that 2d electrodynamics is confining. There is rigorous stuff by Glimm Jaffe Frohlich, which probably merits its own box. There's current algebra and Sugawara construction which comes to its own two decades later, a whole new type of field theoretic construction. There's the anomaly, which started a whole field of inquiry. There's the operator product expansion by Wilson and Zimmermann. There's the S-matrix theorems that are more general than field theory, by Froissart, Coleman/mandula, etc.
- THe 1970s: ignoring supersymmetry--- the field theoretic developments are the renormalization of yang mills, asymptotic freedom, nonperturbative renormalization, ghosts and BRST quantization, vacuum condensate analysis of bound states by SVZ sum rules, and new fermi theories in 2d. There's also the instantons and solitons, the monopoles.
- The 1980s: Renormalization everywhere, and real-space and computational methods. Lattice Gauge theory. Conformal field theory, which probably warrants its own box and page.
- The 1990-now : I think it is fair to say that field theoretic progress is either in applications to high energy physics, or to condensed matter physics or in rigorous type work mathematics/mathematical physics, aside from supersymmetry, where the theories are still being formulated. Even still, there is some new kinds of field theory being formulated, like the "unparticle" theories.
This is the problem with discussion a subject this big and this alive. This was the focus of physics for 80 years. Even if only the really radically new contributions are mentioned, the number of contributers over the decades is enormous. The question is, which period does this box cover? I tried to find some representatives from all eras, excluding rigorous stuff, excluding SUSY, and excluding conformal field theory, maybe that is satisfactory. But the number of even the most obvious contributors is very very large. I don't know how to restrict things in this case.Likebox (talk) 07:36, 13 May 2008 (UTC)
Statistical Field Theory
The condensed matter people probably need their own thing--- how about "Statistical field theory"? This can include Parisi/Zinn-Justin/Kadanoff people who were interested in classical statistics more than quantum fluctuations.Likebox (talk) 18:24, 13 May 2008 (UTC)
- The problem is that "statistical field theory" isn't really a phrase most condensed matter physicists use all that often. Perhaps this template should be renamed to "Quantum field theory in HEP", or "Relativistic quantum field theory", and theirs should be called "Quantum field theory in condensed matter physics," or "non-relativistic quantum field theory." Actually, I feel that this template is too broad to be useful anyway; it needs to be split up. --TriTertButoxy (talk) 15:36, 22 June 2008 (UTC)
- I was getting at more the distinction between the "i" action, quantum fields, and the "-" action, statistical fields. Because they really are two different domains, with some overlap. If you are only interested in the "-" action you get a bunch of interesting nonunitary models, while if you are only interested in the "i" action, you can get models which have imaginary terms in the action, even in imaginary time.
- If you use this dividing line, many-body field theory, the nonrelativistic condensed matter field theory, is included in quantum field theory (because its a quantum system), but the theory of the statistics of fluctuations of self-avoiding random walks or of the Lifshitz point are statistical field theory. I agree that the term is not widely used, but it is used--- Parisi has a book with that title.Likebox (talk) 10:34, 23 June 2008 (UTC)
There was a link to the Rock and Roll drummer Stephen Adler, which isn't the right Adler. There is a physicist with the same name (I think its stephen) who did pioneering work on the anomaly and also the Adler-Weissberger sum rule which is important in deriving physical consequences of current algebra.Likebox (talk) 19:15, 10 July 2008 (UTC)
Foundations vs. Applications
The people listed here are those that have had a big hand in the formulation of quantum field theory, but there are of course hundreds of people who applied the theory to describe the world, and discover the standard model. Sudarshan is one of them, as are Pati, Salam and Georgi. Salam, however, also was the first to give a complete proof that QED was renormalizable, and gave infinite component field theories and superpropagators, and other foundational innovations. But why play "my contribution is more fundamental than yours"? I think there should be different boxes for different things, like the weak interactions, the strong interactions, QED, statistical fields etc.Likebox (talk) 19:34, 30 August 2008 (UTC)
I removed the following people: Michael Werner ( I think he contributed recently to algebraic quantum field theory--- but this is too recent), Pati (whose seminal contributions were to make models of the world, not to the formal development of quantum field theory proper), Sudarshan (ditto--- great scientist--- just doesn't fit here in my opinion), Bose (this was the hardest).
What's the issue with Bose, esp. that Fermi is here? Bose developed the Boson statistics, and his contribution is comparable to that of Candlin, who developed Fermi path integration. Perhaps Bose and Candlin should be included both, but their contribution to the development of the field is in a single paper, and they did not devote an entire career to the subject. Fermi's four-point contact interaction was the first of its kind, and raised issues of unitarity and renormalizability already in the thirties. This is what I thought his contribution to the development of QFT proper was. Same with Bethe--- the Bethe Ansatz showed that S-matrix factorizes in 2D so 2D is magical. But this whole game is a ridiculous exercise and I feel ashamed to cast aspersions on the careers of scientists so great. But there is limited space, and this box needs focus.Likebox (talk) 23:52, 13 September 2008 (UTC)
Standard Model development
A lot of people, including Nicola Cabibbo (and Kobayashi and Maskawa) contributed in very fundamental ways to the standard model. But this box is about the development of the general formalism and physical principles of quantum field theory, not about applications. I am not sure that the same people made as central a contribution to Quantum field theory proper. It is probably good to make a standard model box to acknowledge their contributions.Likebox (talk) 02:01, 9 October 2008 (UTC)
Some of the scientists included in the list of scientist in this template are note notable enough. I invite other editors to state their opinions here and I will edit the template accordingly within a few days. Dauto (talk) 18:50, 24 October 2011 (UTC)