Ioannis wrote:
Sorry, I fail to understand any such difference. FOR ME, the universe
IS my observable universe. The same applies to any other observer. As
such, any other universe (different from one's /observable/ universe)
looks more like of a mental construct than reality, at least to me.

Again, let us drop down one dimension, and suppose that the universe is
a simple sphere. Suppose this universe has age T, and radius R cT;
that is, its diameter is increasing at much faster than the speed of
light. (This is not a violation of the principles of relativity.)

In that case, any individual within the universe cannot see the entire
universe; all he can see is a disc centered on him with radius cT. The
edge of this disc is a logical (i.e., non-physical boundary) edge, and
this is the one you're talking about.

The "edge" that Chris (and earlier Davoud) were talking about is a
different one. I don't think "edge" is the right term, for one should
not think of the *interior* of this spherical universe as being part of
it. The universe proper contains only the surface of the sphere. But
inasmuch as you think of the universe as a kind of inflating balloon,
this edge is the surface of the balloon, not a boundary drawn logically
on the surface.

I suspect that by what you call "the Universe", you may mean that vast
(r~=13 billion ly) mental construct which sits there independent of
human perception. I do not recognise the existence of any such
construct separated from human perception/consciousness.

If I understand you correctly, that is an odd perspective. You mean
that you do not recognize the existence of that which you cannot detect?
I doubt that you mean that--could you clarify?

--
Brian Tung
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