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

Coupled nonlinear partial differential equations or simple matrices?

  1. May 19, 2009 #1
    Why is it impossible to find ALL of einstein's equations in one place? well I suppose its irrelevant, I'd just like to know what math I have to do to define the energy-momentum tensor for a partical if I know say... its energy and momentum, or is that illegal? I'm struggling to grasp general relativity, from a mathematical standpoint; I get it philosophically, help please :(
     
  2. jcsd
  3. May 19, 2009 #2

    atyy

    User Avatar
    Science Advisor

    In general relativity matter is modelled as different sorts of fields, not particles. It is these fields that have energy momentum tensors.

    However, one can talk about a particle moving in curved spacetime as an approximation. In this approximation, spacetime curvature is produced by the energy-momentum tensors of all matter except for a particular particle. The particle then moves on the "background" curved spacetime created by all other matter.

    http://relativity.livingreviews.org/Articles/lrr-2004-6/ [Broken]
     
    Last edited by a moderator: May 4, 2017
  4. May 19, 2009 #3
    I may possibly be even more confused. the question I meant to ask was not how a partical moves but how do I take scalar values like energy and momentum and construct the matrix that defines the energy-momentum tensor, or is that something that only supercomputers, Einstein and Swartzchilde can do?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Coupled nonlinear partial differential equations or simple matrices?
Loading...