On Thu, 18 Feb 2010 22:49:11 -0800 (PST), YKhan
wrote:

On Feb 18, 8:53*am, Antares 531 wrote:
On Thu, 18 Feb 2010 08:44:09 -0500, Yousuf Khan

wrote:
Antares 531 wrote:
What's the most widely accepted position on this. Was the Big Bang a
humongous explosion, or was it a matter of three spatial dimensions
uncurling? If this was an explosion, what did things expand into? Were
the three spatial dimensions we now perceive always there, but
completely devoid of any matter other than the point at which the Big
Bang occurred?

Even if it were dimensional uncurling, you'd still need the energy of an
explosion to uncurl them.

* *Yousuf Khan

This seems right, unless there is some other means, yet unknown,
hiding in the background. * *Gordon

One way to look at it is that the Universe is infinite now, but in the
past when the BB happened, was the Universe finite? The answer is that
the Universe was probably already infinite, even at zero time. The
point from which our section of the Universe grew out of is just the
visible part of a Big Bang that happened in infinite places.

In fact, the only dimension that we have any sort of absolute endpoint
for is the Time dimension. And that endpoint is the Big Bang. Time may
go on forever after this, so there will be no finishing endpoint, but
there is a starting endpoint. So that indicates to me that Time is the
only dimension that got uncurled.

Yousuf Khan

This is a interesting perspective, but I wonder if maybe the universe
may eventually collapse back to the point of origin. If this could
happen, we might still see it expanding within our visible horizon but
it may be already collapsing out beyond our visible horizon. This
would be something like a geyser erupting. The water near the source
would be moving upward while the water on up near the top would be
slowing and eventually reversing, without any discernable effects on
the velocity near the source.

Gordon