Quantcast
  • 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.

News

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

Attributions

(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 ...

  Computation of String Tension in Lattice QCD

+ 0 like - 0 dislike
487 views

There is a quantity called String Tension in lattice QCD calculation.

How is this quantity (String Tension) defined and computed in Lattice QCD? Are there some useful formulas to define it both in the continuum as well as on the lattice?

The attached figure shows an example about the result of computations in gauge theories :

enter image description here

Thanks for the answer, if you can help please!

This post imported from StackExchange Physics at 2020-11-06 18:49 (UTC), posted by SE-user annie marie heart
asked May 29, 2018 in Theoretical Physics by annie marie heart (1,205 points) [ no revision ]

1 Answer

+ 4 like - 0 dislike

Quick answer: The string tension $\sigma$ as shown in that plot (which looks like an older version of Fig. 11 in arXiv:1004.3206) is the dimension-2 coefficient of the linear term in the static potential $V(r)$ (the energy of two infinitely heavy probes separated by spatial distance $r$). So one computes $V(r)$, typically from the exponential decay of rectangular $r\times T$ Wilson loops oriented along the temporal direction, $W(r,T) \propto e^{-V(r)\cdot T}$, and then fits $V(r) = -\frac{C}{r} + A + \sigma r$ to determine $\sigma$.

The stuff above is in continuum language, implicitly working in "lattice units" where the dimensionful lattice spacing is set to $a=1$. Non-zero lattice spacing leads to discretization artifacts in the predictions for the dimensionless combination $a^2 \sigma$, which are removed by extrapolating $a \to 0$. One can play games with lattice perturbation theory to reduce these artifacts.

This is one of the simplest non-trivial calculations one can do in lattice gauge theory, so it should be covered comprehensively in the standard textbooks/lecture notes. Silvia Necco's PhD thesis, hep-lat/0306005, might be a good starting point.

This post imported from StackExchange Physics at 2020-11-06 18:49 (UTC), posted by SE-user David Schaich
answered Jun 20, 2018 by David Schaich (110 points) [ no revision ]

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:
p$\hbar$ysics$\varnothing$verflow
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
...