All Questions
4
questions
2
votes
0
answers
72
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Would the nightsky be bright (filled with starlight) without accelerating space expansion?
As I currently understand, if a photon was emitted from a far away point in the Universe, beyond the event/particle horizon, so that the space inbetween the emitter and us is expanding faster then ...
- 29k
1
vote
3
answers
394
views
Is the highest photon energy currently possible a Planck photon or based on space-time quantinization?
It makes sense that there could be an upper limit to the frequency/energy for individual photons if the universe as we know it is quantized.
But, the highest energy photons I've heard about have a ...
1
vote
1
answer
239
views
How is it possible to infer the time it takes for photons to reach the earth?
The photons emitted from a long, long time ago in a galaxy far, far away arrive at our planet several million or even billion years after the light was first created. So, how do we know, when we ...
- 285
1
vote
4
answers
2k
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Can a photon have little to no energy and/or speed?
Can a photon move more slowly than the speed of light and behave 'non-relativistically,' so to speak. Perhaps another way to express my thought is: could we stop a photon from moving?
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