Is the Universe Curved?

Most recent answer: 11/04/2011

is universe curved?are stars and galaxies adhearing to the universe like a dot on a ballon or are they inside it?hottest temperature must be somewhere in the universe?
- suryanarayana (age 62)
chikmagalur,karnataka,south india
As far as we can tell the universe, observable universe that is, is flat and not curved.  The evidence comes from the uniformity of the CMB, cosmic microwave background.  This information comes for orbiting satellites such as WMAP and PLANCK that measure the microwave radiation at a point and its correlations with radiation at neighboring points.  This distribution is consistent with a "flat" geometry.  
There is no particular "hot spot" in the universe.  It's supposed to be isotropic on large scales. The "dot on a balloon" analogy is not quite right.  It's more like a bunch of dots within a volume element but to an observer on one of these dots, our earth,  all the other dots seem to be getting farther apart. 
There is another web site similar to ours that has a nice response to your question. 


(published on 11/04/2011)