Metric for an observer in free fall two schwarzchild radii from black hole.

AI Thread Summary
To find the metric for an observer in free fall two Schwarzschild radii from a black hole, the correct approach involves substituting r=2rs and dt=d(tau) into the standard Schwarzschild metric. This scenario can be treated as a radial trajectory, allowing for the simplification of d(theta) and d(phi) to zero. The user seeks clarification on these steps as they prepare for an upcoming general relativity exam. The discussion highlights common challenges faced by students in understanding complex concepts in gravitational physics. Overall, the inquiry emphasizes the need for clear guidance in applying general relativity principles.
Sae_Phys
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Hi all,

I have a GR exam on tuesday and getting a bit confused as to how to find the metric for an observer in free fall a distance two schwarzchild radii from a black hole.

I know this is a bit of a basic question but I am just wondering if I am correct to substitute r=2rs and dt=d(tau) into the usual metric and simplify. Also does this class as a radial trajectory so can you set d(theta) and d(phi) =0 ... HELP!

Thanks :)
 
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