Imagine the Universe!
Imagine Home  |   Ask an Astrophysicist  |  
Ask an Astrophysicist

The Question

(Submitted January 14, 1998)

I have seen programs and read books about the Universe. Mainly they speak of it either being constant, never-ending or ever-expanding with the end of the universe happening when it finally collapses upon itself. Could the "Big Bang" be a continuous cycle of collapse and expansion, collapse and expansion....? It goes against everything in me to believe that one day it could end. I don't know how well I have stated my question, but I have always understood that matter is a constant. That paper can be burned and its composition changed, but the atoms are all still present only in a different form. I also understand that change is the only certainty in the universe as we know it, so an end does not seem possible. Has someone who has a respected opinion in this regard discussed it or disregarded this idea?

The Answer

I think this is a question that has occurred to many people contemplating the Big Bang. Historically, cosmologists have fallen into 2 fairly clear categories: those who are very reluctant to contemplate a 'one-shot' universe (we might call them recyclers), and those who are not. Right now there is a preponderance of evidence that the universe will not collapse, based on measurements of the rate of expansion and the mass density. I agree with you that this is somewhat less appealing than recycling. However, I also am interested in how science often challenges my preconceived ideas, and so I am personally interested in keeping my mind open on this subject. Die-hard recyclers will undoubtedly be able to suggest ways of bringing about collapse. You can read more about the Big Bang on our site, for example at:

http://imagine.gsfc.nasa.gov/docs/science/mysteries_l1/age.html

I hope this helps,

Tim Kallman
for the Ask an Astrophysicist Team

Previous question
Prev
Main topic
Main
Next question
Next

If words seem to be missing from the articles, please read this.

Imagine the Universe! is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Project Leader: Dr. Barbara Mattson
Curator: Meredith Gibb
Responsible NASA Official: Phil Newman
All material on this site has been created and updated between 1997-2014.
This page last updated: Thursday, 01-Dec-2005 13:58:39 EST