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Buzz Bloom
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I would like to ask what I hope are two simple questions about what I recognize to be a complicated subject. I did make an effort to search the Internet for the answers, but the two most promising looking sources I found did not help.
Q1: I understand that a mass-less particle moving at velocity c can exist in a circular orbit around a black hole (BH) at radius
What would the shape of its trajectory be if it passed by the BH with its closest position to the BH being
Q2. Is a parabolic trajectory possible? If so, would its closest distance to the BH be
https://www.physicsforums.com/threads/null-geodesics-in-schwarzschild-spacetime.895174/
https://preposterousuniverse.com/wp-content/uploads/grnotes-seven.pdf
The math in these sources is way over my head. There are also issues with not being able to find (by searching the material) definitions of the symbols for some variables. Examples are: italicized λ and L.https://preposterousuniverse.com/wp-content/uploads/grnotes-seven.pdf
Q1: I understand that a mass-less particle moving at velocity c can exist in a circular orbit around a black hole (BH) at radius
R = 2 RS,
where RS is the Schwartzchild radius.What would the shape of its trajectory be if it passed by the BH with its closest position to the BH being
R = RS + ε,
where ε is a very small distance? My guess is that it would be a hyperbola, and I would appreciate knowing if this is correct or not.Q2. Is a parabolic trajectory possible? If so, would its closest distance to the BH be
R < 2 RS?
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