Ioannis wrote:
That's right. Your "detect", above, is my "seeing with my own eyes".
Information from an object outside my observable universe (r=c*t) hasn't
reached me yet, therefore it's as good as non-existent (for me).

By that reasoning, parts of the universe flicker into existence at the
precise moment that you detect them. How is it that the objects there
emitted the photons that allowed you to detect them? How did the
photons traverse space that did not exist at the time?

I'm not trying to put you on the spot; I'm just having trouble seeing
the benefit of equating "detected" (*not* "detectable") with "existent."
It's something you're apparently aware of, so I assume you are OK with
this schema. Suppose you have a brick in front of you, which you cannot
actually touch. Does the interior of the brick not exist for you? For
that matter, does the brick exist, or just the photons that reach your
eye, reflected from the (putative) brick?

You understood correctly. I don't know what "universe" means to you and
Chris, but to me it is THAT, parts of which I can see NOW. Never mind
the fact that what I see may be light from the construct's past.

That seems like a heck of a thing to "never mind." At the least, it
would have prevented the current level of understanding of the Big Bang.

--
Brian Tung
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