• Register
PhysicsOverflow is a next-generation academic platform for physicists and astronomers, including a community peer review system and a postgraduate-level discussion forum analogous to MathOverflow.

Welcome to PhysicsOverflow! PhysicsOverflow is an open platform for community peer review and graduate-level Physics discussion.

Please help promote PhysicsOverflow ads elsewhere if you like it.


PO is now at the Physics Department of Bielefeld University!

New printer friendly PO pages!

Migration to Bielefeld University was successful!

Please vote for this year's PhysicsOverflow ads!

Please do help out in categorising submissions. Submit a paper to PhysicsOverflow!

... see more

Tools for paper authors

Submit paper
Claim Paper Authorship

Tools for SE users

Search User
Reclaim SE Account
Request Account Merger
Nativise imported posts
Claim post (deleted users)
Import SE post

Users whose questions have been imported from Physics Stack Exchange, Theoretical Physics Stack Exchange, or any other Stack Exchange site are kindly requested to reclaim their account and not to register as a new user.

Public \(\beta\) tools

Report a bug with a feature
Request a new functionality
404 page design
Send feedback


(propose a free ad)

Site Statistics

205 submissions , 163 unreviewed
5,047 questions , 2,200 unanswered
5,345 answers , 22,709 comments
1,470 users with positive rep
816 active unimported users
More ...

  Lee-Yang circle theorem

+ 0 like - 0 dislike

what is Lee-Yang circle theorem and what is it used for ?? , i mean given a measure how can you know that is Ferromagnetic and hence all its zeros lie on a Circle ??

the Lee-Yang circle theorem proof is it only valid for the measure $ \delta (x-1) + \delta (x+1) $

how can you proof the Circle theorem for any measure ?? if any measure is positive and EVEN does Lee-Yang circle theorem hold ??

This post imported from StackExchange Physics at 2014-07-18 05:00 (UCT), posted by SE-user Jose Javier Garcia
asked Aug 20, 2011 in Theoretical Physics by Jose Javier Garcia (70 points) [ no revision ]

1 Answer

+ 2 like - 0 dislike

You can start here to get an overview.

From a high level the L-Y Circle theorem is a statement about the location of the zeros of the partition function used in statistical field theory for ferromagnetic systems. It applies when using a mean-field approximation and the zeros of the partition function end up constrained to the unit circle. I can't remember the details of how the proof goes but Itzykson and Drouffe has a very detailed section on the Lee-Yang zeros. Section 3.2 (if I remember correctly) will answer most of your detailed questions as it has a full on proof of the theorem.

This post imported from StackExchange Physics at 2014-07-18 05:00 (UCT), posted by SE-user unclejamil
answered Aug 20, 2011 by unclejamil (140 points) [ no revision ]
L-Y theorems applies much more generally than for mean-fields. As an observation, it is obviously useful for basically any problem but even rigorously it has been extended to much much more (e.g. finite-size corrections have also been computed).

This post imported from StackExchange Physics at 2014-07-18 05:00 (UCT), posted by SE-user Marek

Your answer

Please use answers only to (at least partly) answer questions. To comment, discuss, or ask for clarification, leave a comment instead.
To mask links under text, please type your text, highlight it, and click the "link" button. You can then enter your link URL.
Please consult the FAQ for as to how to format your post.
This is the answer box; if you want to write a comment instead, please use the 'add comment' button.
Live preview (may slow down editor)   Preview
Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
If you are a human please identify the position of the character covered by the symbol $\varnothing$ in the following word:
Then drag the red bullet below over the corresponding character of our banner. When you drop it there, the bullet changes to green (on slow internet connections after a few seconds).
Please complete the anti-spam verification

user contributions licensed under cc by-sa 3.0 with attribution required

Your rights