Ask A Scientist© Astronomy Archive

Author:      gyb
I read in the Paper today that scientists in Hawaii have discovered some-
thing interesting THREE FOURTHS the way across the universe.  How can
scientists see 3/4 the way across the universe?  Since we look back in time
as we look out into space, and since we would eventually see back to the Big
Bang in which all of the matter was in a singularity in the 'center' of the
universe, and since we would see this in all directions, does it not follow
that the center of the universe is everywhere in a previous space/time. 
Conversely, does it not then follow that by going out in all directions from
the center you would eventually come to the edge of the universe which would
be EVERYWHERE in the present space/time?  What I am getting to is that the
statement in the paper leads one to believe that we can see back past the
center and toward the opposite 'edge'.  I am surprised that astronomers
would use such a Euclidian statement.  The geometry of the universe that we
observe is inconsistent with a Euclidian model with the center in the middle
of a sphere and the edge at the surface of the sphere.  A more proper model
would be a space/time 'sphere' with the center representing the surface of
the sphere in a previous time and the center of the sphere representing the
edge of the universe in the present space time.  This model puts any
observer at the edge of the universe looking back toward the center which 
which is consistent with our observations.

Response #:  1 of 2
Author:      jlu
You seem to be generally correct, except that what you read in the paper is
not what astronomers say, but what semi-literate reporters report.  The
"horizon" approaches the "beginning of time".  Everything may become clearer
if you read Steve Weinberg's delightful little book, "The First Three
Minutes". 

Response #:  2 of 2
Author:      jasjeet s bagla
In an expanding universe with a finite age, we can only see a small part of
the universe.  (Hopefully there is more!).  The statement in the report
referred to 3/4 of the size of the visible universe.