I think I'm correct in saying that the light isn't attracted to the mass, but the mass bends spacetime around it, so the path of everything traveling through that medium is bent, including the paths of photons.
Hmm, thanks. I did a little more searching and reading about this with my new vocabulary (bending spacetime). It seems like photons also bend spacetime.
So I'm still wondering if it is proper to think of a star's gravitational field being caused not just by its matter, but also by all the photons it has pumped out over its lifetime.
It doesn't make any sense to define a gravity field by photons. They're massless, so they don't attract anything, and most of the photons a star has produced over its lifetime are speeding away across the universe billions of light years away from it.
Only things with mass can attract other objects with the gravitational force. Photons aren't in that category.
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I think I'm correct in saying that the light isn't attracted to the mass, but the mass bends spacetime around it, so the path of everything traveling through that medium is bent, including the paths of photons.
This effect causis gravitational lensing: http://en.wikipedia.org/wiki/Gravitational_lens
Hmm, thanks. I did a little more searching and reading about this with my new vocabulary (bending spacetime). It seems like photons also bend spacetime.
More info here. All of it contradictory :) http://www.physicsforums.com/showthread.php?t=287888
So I'm still wondering if it is proper to think of a star's gravitational field being caused not just by its matter, but also by all the photons it has pumped out over its lifetime.
It doesn't make any sense to define a gravity field by photons. They're massless, so they don't attract anything, and most of the photons a star has produced over its lifetime are speeding away across the universe billions of light years away from it.
Only things with mass can attract other objects with the gravitational force. Photons aren't in that category.