Talk:Instanton

From Wikipedia, the free encyclopedia

WikiProject Physics This article is within the scope of WikiProject Physics, which collaborates on articles related to physics.
B This article has been rated as B-Class on the assessment scale.
Mid This article is on a subject of mid importance within physics.

Help with this template This article has been rated but has no comments. If appropriate, please review the article and leave comments here to identify the strengths and weaknesses of the article and what work it will need.
This article may be too technical for a general audience.
Please help improve this article by providing more context and better explanations of technical details to make it more accessible, without removing technical details.

Very nice, but the article doesn't actually say what an instanton is. Anyone with enough knowledge of theoretical physics want to take a crack at putting some text in this article? Erik Carson

Followup: Ask and ye shall receive. Erik Carson 19:57, 2004 Mar 30 (UTC)

I am a mathematician trying to understand what this article means mathematically, but am limited by the deluge of physics jargon starting from the very beginning of this article. Could at least the introduction be rewritten to be understandable to someone without graduate-level physics knowledge? - Gauge 04:40, 21 August 2005 (UTC)
I've just rewritten the article so that it explains the more general meaning of the term "instanton". The relation to Yang-Mills gauge theory in Minkowski space should be clarified in a subsection. I apologize for leaving the edit in an incomplete state; it will take some time to get everything right.

U(1) doesn't have instantons. π3(U(1)) = 0. No Abelian gauge theory has instantons. Phys 20:17, 20 October 2005 (UTC)

U(1) gauge theories in two dimensions do have instantons. Spatial infinity here is a circle, and π1(U(1)) = Z. This is the case the author was discussing.</math>

Contents

[edit] Put some "m"

Just put the "m" relating to the mass of the particle where needed in the part about Instanton in Quantum Mechanics

[edit] Typo

The WKB expression for the probability for the particle to tunnel should be real. The i should be replaced with a 2.

http://upload.wikimedia.org/math/5/c/7/5c719dcaa6e7112fb76f501b5f57a598.png —The preceding unsigned comment was added by 71.136.90.228 (talk) 13:03, 7 December 2006 (UTC).

[edit] Noncommutative and SUSY instantons?

Maybe someone could also add at least a note that instantons also exist on noncommutative spacetimes, as well as for supersymmetric gauge theories. And mentioning the ADHM construction would also be good. In particular, its interesting that in the noncommutative case there CAN exist U(1) instantons.

[edit] Factor of two mistake corrected

I deleted the factor of two in front of the cosine in the proof of the BPS-bound.

Matrix1329 11:42, 19 April 2007 (UTC)