1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Momentum conservation under a Gauge Parametrization in string theory

  1. May 8, 2010 #1
    Second attempt here to get an answer, im really lost on this.
    Im reading "A first course in String Theory" by Zwiebach and it says that when applying a general [tex] \tau [/tex] gauge parametrization in the form of [tex] n_\mu X^\mu = \lambda \tau [/tex] we can take the vector [tex] n_\mu [/tex] so that for open strings connected to branes (fixed end points) [tex] n^\mu \mathcal{P}^\tau _\mu [/tex], is conserved.

    But in general momentum is not conserved over the string for dirchlet boundary conditions, without taking into consideration the dynamics of the D-brane, as I understand, so how does applying the general \tau gauge make it so that it is essentially conserved? How can we choose a gauge that will conserve momentum on the string. The string is still going to be connected to a brane after all. Im trying to understand the physical interpretation of this statement.


    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  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