Just note that however you try to define "the photon's frame of reference" you end up with a division by zero, so the definition becomes meaningless. Eg distan

Just note that however you try to define "the photon's frame of reference" you end up with a division by zero, so the definition becomes meaningless. Eg distance traveled is 0 due to length contraction. Time taken is 0 due to time dilation. So what's its velocity? 0/0 = undefined, the question is meaningless. But the velocity is arguably more fundamendal than the distance travelled or time taken, so those aren't truly 0. They're also undefined quantities.