Chern-Simons and massive A^{\mu}

  • Context: Graduate 
  • Thread starter Thread starter IRobot
  • Start date Start date
  • Tags Tags
    chern-simons
Click For Summary
SUMMARY

The discussion focuses on the Chern-Simons Lagrangian for a massive gauge field A, specifically the equation L = -\frac{1}{4} F^{\mu\nu}F_{\mu\nu}+\frac{m}{4}\epsilon^{\mu\nu \rho}F_{\mu\nu}A_{\rho}. The field equations derived are ∂_{\mu}F^{\mu\lambda}=-\frac{m}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}, leading to the challenge of demonstrating that F satisfies the Klein-Gordon equation: (\Box+m^2)F_{\mu\nu}=0. The introduction of the dual field strength, defined as \tilde{F}^\lambda = \frac{1}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}, is crucial for deriving the Klein-Gordon equation for both the dual and the original field strength.

PREREQUISITES
  • Chern-Simons theory
  • Field strength tensor F_{\mu\nu}
  • Klein-Gordon equation
  • Divergence and Levi-Civita symbols
NEXT STEPS
  • Study the derivation of the Chern-Simons Lagrangian in gauge theories
  • Explore the properties and applications of the dual field strength \tilde{F}^\lambda
  • Investigate the implications of the Klein-Gordon equation in quantum field theory
  • Learn about the role of the Levi-Civita symbol in tensor calculus
USEFUL FOR

The discussion is beneficial for theoretical physicists, particularly those specializing in quantum field theory and gauge theories, as well as graduate students seeking to deepen their understanding of Chern-Simons theory and related equations.

IRobot
Messages
86
Reaction score
0
Hi, I am struggling with a problem in field theory:
We are looking at a Chern-Simons Lagrangian describing a massive A field:
L = -\frac{1}{4} F^{\mu\nu}F_{\mu\nu}+\frac{m}{4}\epsilon^{\mu\nu \rho}F_{\mu\nu}A_{\rho}
I find those field equations:
\partial_{\mu}F^{\mu\lambda}=-\frac{m}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu} and now I need to show that F satisfies the Klein-Gordon equation: (\Box+m^2)F_{\mu\nu}=0 using the EL equations, but after a time playing with both equations, I still can't prove that.
 
Last edited:
Physics news on Phys.org
It's normal here to introduce the dual of the field strength

\tilde{F}^\lambda = \frac{1}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}.

Then taking the divergence of your equation of motion above yields \partial_\lambda \tilde{F}^\lambda = 0, while multiplying by an appropriate epsilon yields the KG equation for \tilde{F}^\lambda.
 
fzero said:
It's normal here to introduce the dual of the field strength

\tilde{F}^\lambda = \frac{1}{2} \epsilon^{\lambda\mu\nu}F_{\mu\nu}.

Then taking the divergence of your equation of motion above yields \partial_\lambda \tilde{F}^\lambda = 0, while multiplying by an appropriate epsilon yields the KG equation for \tilde{F}^\lambda.
Thanks a lot. I did manage to find the Klein Gordon equation for the dual, then it's just a matter of applying another LeviCivita to find it for the "regular" form. ;)
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 24 ·
Replies
24
Views
3K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K