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As far as I know for a photon that's moving at the speed of light (obviously) time comes to a halt and space contracts to a point, making all travels instant from its perspective. Now this is the part I might have understood wrong, so please correct me if what I've said isn't true.

Yet supposing it's true, then how can a photon differentiate between travelling say one meter and being absorbed by some electron and going through space unobstructed for 10 billion light years? To me it seems like both of these travels are instant from its perspective, yet we know that one is shorter and the other is longer from the perspective of an observer who is slower than light.

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    $\begingroup$ "As far as I know for a photon that's moving at the speed of light (obviously) time comes to a halt and space contracts to a point, making all travels instant from its perspective. "...No. There is no "perspective of a photon", see e.g. Ben Crowell's answer to another variant of this question. $\endgroup$ – ACuriousMind Mar 29 '15 at 14:56
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As far as I know for a photon that's moving at the speed of light (obviously) time comes to a halt and space contracts to a point, making all travels instant from its perspective. Now this is the part I might have understood wrong, so please correct me if what I've said isn't true.

It isn't true I'm afraid. Imagine you were travelling though this universe at a speed that was so close to the speed of light that we couldn't tell the difference. What perspective do you have? None! You are subject to a virtually-infinite time dilation, such that you are effectively a frozen popsicle. For example if I knew your course in advance, I could laboriously tug an asteroid and place it in your path. You wouldn't see it. Then BLAM, that's the end of you and your so-called perspective.

How can a photon differentiate between travelling say one meter and being absorbed by some electron and going through space unobstructed for 10 billion light years?

It can't. Both of these journeys might seem to be instant from its perspective, but it doesn't have any perspective.

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