In a TV ducumentary, I heard that time started with Big Bang, and it is meaningless to talk of "before". This was given without any further explanation, in the peculiar, irritating style of documentaries.
Now I wonder if this fact may be motivated by the means of motion. Time, afaik, is necessarily measured (or even defined) by motion. "Prior" to Big Bang, no motion, no time.
Is that correct?
NOTE: I have a degree in mathematics (BSc), but almost no knowledge of modern physics, so treat me as a layman when talking about it.