What does the 2.7 Kelvin microwave background tell us about some of the currently fashionable cosmological...?

Question

What does the 2.7 Kelvin microwave background tell us about some of the currently fashionable cosmological theories?

Answer 1

Check the WMAP entry in wikipedia and check the WMAP website itself (although some of it is quite technical).

The one thing that got my attention is that the universe is not small. Had the universe been small (e.g., a "mere" 100 billion light-years) there would have been tell-tale signs in the background. They are not there.

It is now more fashionable to consider the universe to have infinite extent in 3-D (although space-time still appears to have a border in 4-D: located nearly 14 billion years in the past).

WMAP data also seems to confirm that the amount of matter (baryonic + dark) is still insufficient to cause the universe to stop expanding (Omega is still less than 1 when considering matter only). It also appears that the expansion is really accelerating (bringing in the need to imagine a "dark energy")

Answer 2

That there are absolutely wrong. That currently fashionable cosmological theory is creationism of course.

The microwave background radiation is very strong evidence for the Big Bang theory which has been around a while and has yet to be disproven. Thus it cannot be called "a fad".