Why is the 4-dimensional entity of the universe not argued to be the beginning of the universe but instead t=0?

Arguably, the 4-dimensional entity is our best understanding of what the universe is, if but our beginning understanding of it.

 

Otherwise, I suggest that is has been argued that the universe is a three-dimensional object that exists along time.

Edited September 28, 20169 yr by Genecks

Because 'beginning' is a measure of time.

( not length, width or height )

By beginning we need some notion of 'after' and so time is explicitly involved. Classically we can 'rewind' our models to 't=0', but at this point the physics breaks down. It is quite possible that, because of quantum effects, that 'before' and 'after' are not really workable concepts when we get close to the 'beginning' of the Universe.