Seeing Across the Universe ```Name: Gyb Status: N/A Age: N/A Location: N/A Country: N/A Date: 1993 - 1999 ``` Question: I read in the Paper today that scientists in Hawaii have discovered something 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 w hich 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 t he 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 su rface 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 mod el puts any observer at the edge of the universe looking back toward the center which which is consistent with our observations. So... Replies: 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". J Lu In an expanding universe with a finite age, we can only see a small part of the universe. ( Hopefully there's more ! ). The statement in the report referred to 3/4 of the size of the visible universe. Jasjeet. Click here to return to the Astronomy Archives

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