If the Big Bang created space time, what did the singularity of the Big Bang "rest" on?
The "singularity" is just the place where out math model breaks down. It is not a physical place/thing. The Big Bang Theory is silent about what happened earlier than one Plank Time after the singularity, it just described what happened SINCE one Plank Time.
I'm sorry I worded that incorrectly.
Well, if I did not answer your question, then re-ask it with different wording.
What did the mass that made the Big Bang rest on if their wasn't the fabric of space time?
I'm sorry I have trouble expressing what's in my mind with words sometimes.
Unknown. We have no reliable/testable theory as to anything prior to one Plank Time. There are theories, including that space-time was created at the singularity, that space-time has always existed, that there are multiple universes, take your pick. Since none of them are supported by any evidence, I personally am just agnostic about the whole thing.
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