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DiracPool

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http://en.wikipedia.org/wiki/Chronology_of_the_universe

http://en.wikipedia.org/wiki/Graphical_timeline_of_the_Big_Bang

...and wasn't able to find an answer to a question I have.

That question is, is there any evidence that the spatial and time dimensions unfolded in any certain order, or, as the saying goes, "did all 4 dimensions just spring forth simultaneously and fully formed from the head of Zeus?"

For example, I typically think of "time" as the 4th dimension, which implies a sense of seriation. I think of it as coming last. I think of the first dimension as coming first, the second second, the third third, and the fourth time. I think of these dimensions as "evolving" out of one another. Maybe I think that way because that is really how we learn these things. We typically model systems when we learn them in one dimension, using ODE's, and then only invoke the Laplacian, reluctantly, when we need to or want to step up our game, so to speak.

But the origin of the universe? I was looking into the Hartle-Hawking state: http://en.wikipedia.org/wiki/Hartle–Hawking_state

The Hartle–Hawking state is the wave function of the Universe–a notion meant to figure out how the Universe started–that is calculated from Feynman's path integral.

More precisely, it is a hypothetical vector in the Hilbert space of a theory of quantum gravity that describes this wave function.

It is a functional of the metric tensor defined at a (D − 1)-dimensional compact surface, the Universe, where D is the spacetime dimension. The precise form of the Hartle–Hawking state is the path integral over all D-dimensional geometries that have the required induced metric on their boundary. According to the theory time diverged from three state dimension – as we know the time now – after the universe was at the age of the Planck time.

What does that mean? "Time diverged from the three state dimension?" From what I understand, all we know is that the whole thing got kicked at 10^-43 seconds, the so-called, "Planck time." So it seems to me that the "Time" dimension had to have come first, OR, all 4 dimensions must have come into existence simultaneously. Does anyone have some insight on this?