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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!

**Topics:**Astrophysics gravity light

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## Tify Ndanoboi 50+

## A wal

## Tify Ndanoboi 50+

## A wal

No it doesn’t. You were saying you were having trouble visualising it. String theory isn’t needed for the universe to be spherical. That’s the only way it can make sense imo. I don’t believe in infinity in any real sense and I don’t see the universe having edges somehow, so that’s the only way I think it can work. Relativity doesn’t prove it but it definitely suggests it.

## Tify Ndanoboi 50+

I don’t believe in infinity in any real sense ... that may well be a problem specifically regarding the mathematics of all the disciplines involved. Specifically if one requires to have any kind of proof, rather than a supposition.

## A wal

Are you talking about the mathematics of a hypersphere? That's already known. If you're talking about the difference between the mathematics of describing the universe in this way vs the maths of describing it beginning from a gravitational singularity then there's no difference because from our perspective the universe does shrink into a singularity as we look back into the past, because it's a sphere. It's not just what it looks like from our perspective, it's what actually happened from our perspective, but that's not what it would look like if we were there. It would look just like this.

It makes so much more sense than thinking the universe is actually smaller in the past. As we look across the curved surface objects get more red-shifted as we're looking across more of a curved surface. If we look far enough in any dimension then everything funnels into a singularity. Look up dark flow.

## Tify Ndanoboi 50+

## A wal

You have some very deep misconceptions about mathematics if you think it can be used as evidence of anything. It's a description of a model, nothing more. It can be used to make predictions, but even that's not real proof. It's impossible to prove a theory right. It can only be proved wrong. All you can do is say that the data matches the model. To do that the model needs to be unambiguous. That's what mathematics is for.

You need to forget schooling because it obviously didn't work properly and learn to think for yourself. Good luck.