In summary, according to Hawking [1], light photons at the event horizon of a black hole will cease to move and remain motionless for the entire lifetime of the black hole. Additionally, observations and calculations have shown that the path of light can be bent by a sufficiently massive object due to the curvature of spacetime. It is possible for a photon to orbit an object due to their gravitational attraction, as there is a circular light-like orbit at 3/2 times the Schwarzschild radius, known as the photon sphere. This phenomenon has been observed and has implications for our understanding of gravity as a long-range force.
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H Smith 94
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According to Hawking [1] it is posited that light photons at the event horizon of a black hole must cease to move, and remain motionless for the entire lifetime of the black hole.

It is also observed [http://dls.physics.ucdavis.edu/~scranton/LensedCMB/a2218.gif] (and calculated) that the path of light will be bent by a sufficiently massive object, due to the curvature of spacetime around that object.

Now, since gravity is a long-range force, I was wondering if it is possible for conditions to exists under which a photon could orbit an object due their gravitational attraction? If so: what would these conditions be; how can we observe it; and what implications, if any, does this have?
 
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H Smith 94 said:
According to Hawking [1] it is posited that light photons at the event horizon of a black hole must cease to move, and remain motionless for the entire lifetime of the black hole.
Note that this is only true for light that would be moving radially outwards. All other light will inevitably enter the black hole and eventually reach the singularity.

H Smith 94 said:
I was wondering if it is possible for conditions to exists under which a photon could orbit an object due their gravitational attraction?

There is a circular light-like orbit at 3/2 times the Schwarzschild radius.
 
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H Smith 94 said:
I was wondering if it is possible for conditions to exists under which a photon could orbit an object due their gravitational attraction?
https://en.wikipedia.org/wiki/Photon_sphere
 
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Related to Can Light Orbit a Massive Object?

1. Can light be affected by gravity?

Yes, light can be affected by gravity. In fact, according to Einstein's theory of general relativity, gravity is the curvature of space-time caused by massive objects. This means that light, which travels in a straight line through space-time, will also follow this curvature and be affected by gravity.

2. How does the curvature of space-time affect light?

The curvature of space-time caused by a massive object, such as a planet or star, can bend the path of light. This is known as gravitational lensing and it can be observed when light from distant objects is bent around a massive object, creating distorted or multiple images.

3. Can light orbit a massive object?

No, light cannot orbit a massive object in the same way that planets orbit a star. This is because light has no mass and therefore cannot be affected by the gravitational force needed to maintain an orbit. However, light can follow a curved path around a massive object due to the curvature of space-time.

4. Is it possible for light to escape a black hole's gravitational pull?

Yes, it is possible for light to escape a black hole's gravitational pull, but only if it is outside the event horizon, which is the point of no return. Inside the event horizon, the gravitational pull is so strong that not even light can escape, which is why black holes are invisible.

5. Can light be trapped in the gravitational pull of a massive object?

Yes, light can be trapped in the gravitational pull of a massive object if it is within the event horizon of a black hole. This is known as a photon sphere and it is a region where light orbits the black hole in a circular path. However, outside of the event horizon, light can escape the gravitational pull of a massive object.

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