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

I Help to understand the Retarded Function

  1. Nov 26, 2016 #1
    Hi people, help here please
    When the Einstein equation are linearized the results are the weak field Einstein equations

    $$
    \left ( -\frac{\partial^{2}}{\partial t^{2}} + \nabla^{2} \right ) \bar h^{\mu\nu}=-16\pi T^{\mu\nu}
    $$
    a solution for this equations considering the source are the Retarded function
    $$
    \bar h^{\mu\nu} (t,\vec x)=4 \int d^{3}x' \frac{[T^{\mu\nu}(t',\vec x')]_{[ret]}}{|\vec x - \vec x'|}
    $$
    with

    $$t' = t_{ret} = t-|\vec x - \vec x'|$$

    until i know "t" and "x" in spacetime are the same but what physical situation describes
    $$
    |\vec x - \vec x'|
    $$
    Is similar to electromagnestism, when $$\vec x$$ represent the place where you want calculate the potencial and $$\vec x'$$ represent the place where the charge is located?

    Thanks in advance
     
    Last edited by a moderator: Nov 26, 2016
  2. jcsd
  3. Nov 26, 2016 #2

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Your weak field equation is just a separate wave equation for every individual component. The solution is just applying the retarded Green's function of the wave equation.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Help to understand the Retarded Function
Loading...