How is light affected by the gravity of a black hole?

AI Thread Summary
Light, despite having no mass, is affected by the gravity of a black hole due to the principles of general relativity, which state that gravity results from the curvature of spacetime caused by energy, momentum, and pressure. Photons, while massless, possess energy and momentum, allowing them to be influenced by gravitational fields. This interaction means that light can be bent or pulled by the gravity of massive objects like black holes. The discussion highlights a common question in physics regarding the relationship between massless particles and gravity. Understanding this concept is essential for grasping the effects of gravity on light in the context of general relativity.
Oliver3.141
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Hello! I am new to this forum, but I'll give it a shot.
It is my understanding that photons have no mass- but that light is still pulled by the gravity of a black hole. How can something without a mass, and therefore, gravity, be pulled by the gravity of another object? Any insight would be appreciated. I am still just beginning in my physics education, so please correct any errors I have made.
 
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Hi Oliver3.141 welcome to PF,

In general relativity (the theory that describes this) gravity comes from the fact that energy and momentum and pressure all curve spacetime. Light travels through spacetime, so its path can be influenced by gravity. Also, light has energy and momentum and pressure, so it can produce gravity too.
 
Thank you for your input! :)
 
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