Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Peskin equation (6.46)

  1. Dec 21, 2011 #1
    I don't quite get the argument peskin used to obtain equation(6.46), page 191:
    He said"The integral vanishes by symmetry unless [itex]\mu=\nu[/itex]. Lorentz invariance therefore requires that we get something proportional to [itex]g^{\mu\nu}[/itex]......".
    I don't understand the "Lorentz invariance therefore....." part. How can one deduce from Lorentz invariance that LHS is an invariant tensor?
    I can convince myself the result by arguing spherical symmetry of the integrand, but I just want to understand Peskin's reasoning.
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted