Can Photons Actually Orbit Massive Objects?

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    Orbit Photons Theory
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SUMMARY

Photons can theoretically orbit massive objects, specifically black holes, according to Einstein's theory of general relativity. The critical radius for a circular photon orbit is defined as r = 3GM/c², where G is the gravitational constant, M is the mass of the black hole, and c is the speed of light. However, this orbit is unstable; photons do not accumulate in this orbit and will either fall into the black hole or escape to infinity.

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  • Understanding of Einstein's theory of general relativity
  • Familiarity with the concepts of black holes and their properties
  • Knowledge of gravitational physics and the Schwarzschild radius
  • Basic comprehension of the behavior of light in gravitational fields
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  • Research the implications of unstable photon orbits in astrophysics
  • Explore the mathematical derivation of the Schwarzschild radius
  • Learn about gravitational lensing and its connection to light bending
  • Investigate the properties of black holes and their event horizons
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Astronomers, physicists, and students of astrophysics interested in the behavior of light in strong gravitational fields and the properties of black holes.

sheriefer
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According to Einstein's theory of general relativity, light bends--or rather space bends--around mass. So, in theory, is it possible for a photon to orbit around a body of sufficiently large mass?
 
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Well, I think that this is possible - black holes are such objects.
 
Yes, a circular photon orbit is possible at r = 3GM/c2. (The Schwarzschild radius, which defines the 'surface' of the black hole is 2GM/c2) However the orbit is unstable, meaning that photons won't accumulate there, and any photon that is placed there will eventually fall into the hole or run off to infinity.
 

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