Litigious wrote:
Space has a boundary. Why shouldn't time have? And if time has a boundary, things don't come out of "nothing", they just have a boundary in time, like they have in space and like they have a finite mass.
I'm not sure space itself has a boundary, except when you take into account time, which it does in at least one direction (the Big Bang).
I personally have a concept of time called "metatime", which encompasses all relative time (including time before the Big Bang). I think of it in appearance as a rather badly and irregularly-woven blanket. You may not get the analogy,
Consider an event like World War 2, and let us assume that most known spacetimes (ie parallel universes) has had World War 2 take place. This would appear to be a big woven "knot" in this blanket, with individual threads coming off it at irregular intervals (say if Mosley got his act together and used the Blackshirts to cause a facist coup in England, or perhaps the Japanese did not bomb Pearl Harbour, but somewhere else, or if the Nazis built the atomic bomb first, and so on).
Each universe's relative spacetime is one of those threads on the blanket.
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(No longer a mod)
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