[allmost]

time is not a constant.

[Kevmo]

It never was.

But C, the speed of light, was postulated to be a constant by Einstein. Now it’s looking more like a decaying function.

[Lokibob]

Nothing in the theory of relativity is a constant, it is all relative to the observer. Not time, speed, distance, energy, mass, or speed of light. Speed is a measure of time vs. distance, and if time is relative or distance is relative, than the speed of light has got to be relative.

.....Bob