According to special relativity, a photon traveling at the speed of light, does not “experience” time. It is traveling into the future at an infinite rate, right?
That would mean that everything that could ever happen (my death, Trump winning the election, death of sun, end of the universe), has already happened (from the frame of a photon). We're just too "slow" to experience this.
Is this correct? Because that would bring some weird implications about free will, and the very nature of our existence. If everything has already happened, then we're just following a predetermined path.
Edit 1: I'm genuinely fascinated by this topic, however, I am also an idiot with very superficial knowledge, gained mostly from youtube videos and Wikipedia. Bear that in mind :)
Edit 2: The nature of my question seems to leave the realm of physics and cross into a philosophical issue. I was seeking physical explanation, to help answer something of philosophical nature, as both these realms seem to coincide for this particular topic.
Some have pointed out that thinking about the frame of a photon doesn't make sense. Instead, one could assume a spaceship traveling at $0.9999c$.
Answer
This is an idea known as the block universe. The example of a photon is a bit extreme, since photons have no rest frames, but the idea is the same: to a fast-moving observer, our future might lie in their past, suggesting that our future already exists.
However, these are purely philosophical notions. In order to see what physics has to say about it, we need to translate "the future already exists", which is a bunch of words, into an experiment that can actually be performed.
One such experiment would be to attempt to receive signals from the future, such as the result of a coin flip. However, relativistic causality forbids this from happening, and also rules out any and all similar experiments. Physics really has nothing to say about this question.
You might complain, why would we have to experimentally test this? Isn't the future already existing directly baked into the math of special relativity, which we know is true?
It is, but you have to be careful not to mix up features of the mathematics of a theory with the theory's predictions. Showing that the predictions are correct does not show that the mathematical structures used to make the predictions are ontologically real. For example, quantum mechanics has a huge variety of flavors, all of which have different ontologies (wavefunction collapse, many worlds, pilot waves) but identical predictions.
Physics can't distinguish between them. Deciding which interpretation of quantum mechanics is right, or whether Lorentz invariance says anything about free will, is a job for the philosophers.
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