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Homework Help: Find Null Geodesics with affine parameter

  1. May 29, 2016 #1
    1. The problem statement, all variables and given/known data
    The metric is given by
    https://dl.dropboxusercontent.com/u/86990331/metric12334.jpg [Broken]
    H is constant; s is an affine parameter, and so r(0)=t(0)=0.

    Apologise in advance because I'm not very good with LaTex. So I used Word for equations, and upload handwritten attempt at solution :smile:

    2. Relevant equations
    Need to show that the null geodesics from r=0, t=0 are given by
    https://dl.dropboxusercontent.com/u/86990331/metricquestion.jpg [Broken]

    3. The attempt at a solution
    I get the required t but the sign is different.
    https://dl.dropboxusercontent.com/u/86990331/metricattemptatsolution.jpg [Broken]
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Jun 3, 2016 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Jun 4, 2016 #3
    Hello, please attempt to re-upload the images, currently the links appear to be broken and may very well be the reason no one can help.
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