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If gravity bends light, how do we know we're not looking at the same old light going round and round in circles?

I've been musing over this for years but never thought of putting it on here. Happily, I came across Jah Kable's post suggesting the same thing. His conversation was closed though, but I don't think the question was answered. The question is; if light can be refracted by a strong gravitational field, black hole, sun, etc. then given enough objects in its path, could it not be slingshot all over the universe? If this is true, all the stars we can see at night might be (have once been) in a radically different position to where we see them now. We might even be seeing light from the same star in two places, or more. Imagine light is a ribbon strewn around the universe, twisted round gravitational objects. If that ribbon happened to pass by Earth more than once, we'd count it more than once in our sky, and each time it would look a different age and as if it were coming from a completely different direction.
There must be someone who can calculate whether this is possible or not! Trouble is, how would we know which objects are (were) real and therefore capable of bending the light and which are the resultant image of light that's already done umpteen laps of the cosmos?! It's bending my head, I know that much!

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    Jul 7 2013: It would not matter either way anyways. When we look at the sky we look millions of years into the past. The nearest black hole to us isn't exactly close enough to bend our light. It's like a telescope, we are looking out from the inside of our galaxy, so things are clear. If we were looking inside from elsewhere, things may look distorted. I wouldn't be too concerned about this.

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