Not signed in (Sign In)

Not signed in

Want to take part in these discussions? Sign in if you have an account, or apply for one below

  • Sign in using OpenID

Site Tag Cloud

2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry book bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics comma complex complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration finite foundation foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory stack string string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to nForum
If you want to take part in these discussions either sign in now (if you have an account), apply for one now (if you don't).
    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJul 29th 2011

    at effective quantum field theory I have started writing an Idea-section and added more reference

    • CommentRowNumber2.
    • CommentAuthorzskoda
    • CommentTimeJul 29th 2011

    In my memory, there were at least two distinct notions of effective field theory, as my colleagues in Wisconsin, like Ted Allen, used to say, “ordinary” and “Wilsonian”.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJul 29th 2011
    • (edited Jul 29th 2011)

    Hm, okay. I am not sure. I should try to educate myself better about some details.

    It is somewhat remarkable how many things about effective QFT are not in the folk lore. For instance the standard statement that computing perturbative quantum gravity effects is impossible due to non-renormalizability is simply wrong. As an effective QFT gravity is as good as any other. In fact even better, as that introduction by Donoghue nicely emphases. He explicitly computes a quantum gravity effect there.

    • CommentRowNumber4.
    • CommentAuthorzskoda
    • CommentTimeJul 29th 2011

    For these questions on what is and what is not possible about quantum gravity, I heard very interesting ideas form Jarah Evslin including that the finite age of universe may be relevant!He was thinking about that a lot and has many alterantive proposals.

    • CommentRowNumber5.
    • CommentAuthorzskoda
    • CommentTimeJul 29th 2011

    Wilsonian vs 1Pi effective actions in particle physics (I am not sure if this is the disctinction we were talking at the time ago):

    http://particlephd.wordpress.com/2009/08/17/wilsonian-vs-1pi-actions

    hep-th/0701053

    I remember at the time when Seiberg-Witten (at the time in N=2 incarnation) stuff appeared we had some series of journal club seminars, and one of the references was emphasising that it was not an ordinary but Wilsonian action. I had to prepare a talk for the latter for the next week, but I was too busy and did not. Then the seminar broke for few weeks and eventually I never gave that seminar.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeJan 31st 2018
    • (edited Jan 31st 2018)

    I have now filled in content spelling out the rigorous formulation of effective quantum field theory in terms of causal perturbation theory, following Fredenhagen-Dütsch et. al.: here.

    Incidentally, regarding #2 above (from many years ago): This rigorous formulation allows a simple proof that the standard effective action S effS_{eff} (in the sense of Feynman perturbation series over connected diagrams) does equal the Wilsonian effective action S eff,ΛS_{eff,\Lambda} for Λ0\Lambda \to 0 (this prop.). This is generally a point of confusion in the traditional non-rigorous formulation (e.g. Physics.SE discussion here).

    I should eventually split off some little entries from the new material at effective QFT that deserve being stand-alone, such as UV cutoff, counterterms, Polchinski’s flow equation and maybe Wilsonian RG. Right now all these terms redirect to effective QFT.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeJan 31st 2018
    • (edited Jan 31st 2018)

    I wrote:

    I should eventually split off some little entries from the new material at effective QFT that deserve being stand-alone, such as UV cutoff, counterterms, Polchinski’s flow equation and maybe Wilsonian RG. Right now all these terms redirect to effective QFT.

    I see now that a stub entry counterterms already existed. So I have now expanded there a little, for the moment with pointer to the material at effective QFT. For completeness I have then also split-off interaction vertex redefinition as a separate entry (which used to redirect to Stückelberg-Petermann renormalization group).

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeFeb 1st 2018
    • (edited Feb 1st 2018)

    I have spelled out the proof of “Polchinki’s flow equation”: here.

    (For entertainment you should compare to the original account in Polchinski 84, (27).)

    [edit: so I have split this off as a stand-alone entry: Polchinski’s flow equation]

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeMar 19th 2019

    added pointer to today’s

    • Eran Palti, The Swampland: Introduction and Review, lecture notes (arXiv:1903.06239)

    diff, v53, current

    • CommentRowNumber10.
    • CommentAuthorUrs
    • CommentTimeMar 19th 2019

    added pointer to today’s

    • Eran Palti, The Swampland: Introduction and Review, lecture notes (arXiv:1903.06239)

    diff, v53, current

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeMay 28th 2019

    added pointer to this relatively new textbook:

    diff, v54, current

    • CommentRowNumber12.
    • CommentAuthorUrs
    • CommentTimeJan 3rd 2020
    • (edited Jan 3rd 2020)

    added pointer to today’s

    diff, v57, current

    • CommentRowNumber13.
    • CommentAuthorUrs
    • CommentTimeJul 1st 2020

    added pointer to today’s

    • Riccardo Penco, An Introduction to Effective Field Theories (arXiv:2006.16285)

    diff, v62, current

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeSep 27th 2020

    added pointer to

    • C. P. Burgess, Introduction to effective field theory, Cambridge University Press 2020 (ISBN:9781139048040)

    diff, v63, current

    • CommentRowNumber15.
    • CommentAuthorNikolajK
    • CommentTimeSep 28th 2020
    • (edited Sep 28th 2020)

    Is it known whether this book differs a lot from the rather short 2007 text of the same title on the authors arxiv?

    https://arxiv.org/abs/hep-th/0701053

    • CommentRowNumber16.
    • CommentAuthorUrs
    • CommentTimeSep 29th 2020

    I don’t know, but I have added the arXiv pointer to the entry, thanks.

    diff, v64, current

    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeJan 13th 2021

    added pointer to today’s

    diff, v65, current