Consider a model in which we let a body fall (radially) into a star, being the simplest example of the schwarzschild solution, in which the angular parts of the solution may be ignored, so that we consider:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

ds^2 = -(1- GM/r) dt^2 + (1- GM/r)^{-1}dr^2.

[/tex]

I have been told that this may be adapted to a Lagrangian of form:

[tex]

L(r, \dot{r}) = -(1- GM/r) (\frac{dt}{d\lambda})^2 + (1- GM/r)^{-1}(\frac{dr}{d\lambda})^2,

[/tex]

and then solved to find a general time for a body to 'fall' from rest, from a general distance R. How, I don't know (...I love supervisors).

I now have 13 books out upon general relativity, and am royally stuck. It is important that a solution avoids tensor calculus- i am aware that this is possible.

Any help with this would be incredibly appreciated.

Regards

Romeo.

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# Urgent Help required- schwarzschild solution

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