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bizerl - hopefully pete will drop by and post on this question, it is right up his street.
Quote from: imatfaalbizerl - hopefully pete will drop by and post on this question, it is right up his street. Sorry but the way it's described is far too confusing for me to follow.
I'm so disappointed because I know if you understood my word salad, Pete, you'd be able to answer easily. I'm sure I'm just missing something fundamental in the way gravitational lensing works.
When light travels through space, it travels in a "straight line" unless spacetime is warped by mass, in which case a "straight line" becomes curved. I'm wondering whether gravity works the same way?
If we represent gravity as a whole bunch of threads connecting say, the moon and the Earth, can those threads be curved by distortions in spacetime, the same way light is curved?
The gravitational deflection of light based on Newtonian theory and the corpuscular model of light was calculated, but never published, around 1784 by Henry Cavendish, almost 20 years earlier than the first published calculation by Johann Georg von Soldner. The two results are slightly different because, while Cavendish treated a light ray emitted from infinity, von Soldner treated a light ray emitted from the surface of the gravitating body. At the first order of approximation, they agree with each other; both are one‐half the value predicted by general relativity and confirmed by experiment.
Am I over-simplyfying gravity?
Hoping you're still out there Pete...
So. If we see the light from a star during an eclipse that is actually behind the sun, but appears to the side, do we feel the effects of gravity as if it was behind or do we feel the effects of gravity from where it appears.
Quote from: bizerlSo. If we see the light from a star during an eclipse that is actually behind the sun, but appears to the side, do we feel the effects of gravity as if it was behind or do we feel the effects of gravity from where it appears.Okay. Now I see what you're asking.The answer is that we feel the effects of gravity from where it appears, i.e. at the sun itself. That is to say that the source of gravity is the sun and the sun generates a gravitional field and curves spacetime and its that which is bending the light.
Okay, different spin on the question; if the above situation referred to by bizerl exists and a further source of gravity waves is introduced so that those waves encounter the bit of space bent by the existing gravity source, what will those gravity waves do? Are they bent by the gravity source, or do they continue in a straight line?