I've looked up this question on the web, and I've gotten seeming conflicting answers.(adsbygoogle = window.adsbygoogle || []).push({});

According to Feynman's path integral - to find the probability of a photon being at A at time 1 and B at time 2 can be determined by taking an integral of the photon traveling over all possible paths. I understand that these paths more than anything are mathematical constructs and should not be taken super literally (since classical trajectories don't really make sense for quantum particles)

Regardless, I have seen on the internet that for points outside of the light cone, the integral results in very low probability of photons being detected, but still nonzero. This effect apparently becomes more significant for very small distances, and goes to zero at larger distances. This would mean there is an exponentially decaying probability of the photon having a speed greater than c. However, in other places I've seen people say pretty strictly that no it is not possible for the photon to have even slightly larger values of c. Even still, I've seen people say that while the photon may travel faster than c, information cannot. This I don't understand. If a photon is known to have been emitted at time 1, and absorbed at time 2, and this is faster than the speed of light - how did information not travel at the same speed? Though I know this has some implications on Causality..

So what is the truth?

Thanks.

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# I Can Photons travel faster than c?

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