Expert: Ed - 4/22/2006

Question
How could the cosmological constant affect the
shape of the universe ?
we know that one important factor in determining the geometry of the universe is
its density in matter compared to the critical density, but what would be the effect of dark energy(or
cosmological constant),if any, on this ?

thank you very much


Answer
Reza,
I recommend that you try to read up on NASA's WMAP mission.  There has been a lot of cutting-edge science done there, on questions of this nature.  Here are some very useful links from the WMAP website:

http://map.gsfc.nasa.gov/m_uni/uni_101shape.html
http://map.gsfc.nasa.gov/m_uni/uni_101accel.html

To answer your question -- the value of the concept of dark energy, (or the cosmological constant), to cosmology, is that it would help support the theory that the universe has a flat shape, which has been powerfully supported by WMAP.

This is a website created by the astronomy dept at the University of Colorado.  Maybe it will help you more:
http://super.colorado.edu/~michaele/Lambda/why.html

I think this is basically what you are asking me.  Please e-mail me here again, if you need more input.  Also, it would help me if you told me if you are a high school student, college, or just an interested adult.  Or, if this answers your question sufficiently, that's fine too.

Keep Looking Up!
--Ed