Thanks for this explanation!
Physics is amazing stuff.
The concept that photons experience no time at all is mind boggling.
That implies that to a photon traveling from Deneb (a star 2600 light years away) to Earth, it would appear it arrived on Earth instantly after being emitted by Deneb!?
Yes thats the most common theory of light, however it is possible it travels slightly under the the universal speed limit, which if that was the case all hell would break loose and all our theories would go tits up. but it is extremely hard to measure the universal speed limit if you dont consider light.