Cold Universe Explanations.

1) The energy is REDSHIFTED out of existence.

By the time radiation from the edge of the universe reaches us, it's redshift is so huge that it contains hardly any energy.

This effectively halves the energy of the universe, U, to 5.2 x 10-13 Joules / m3 which drops the predicted temperature to:

T = (U / a) 1/4 = 5.13° K

A degree colder, but not enough.

2) The energy is absorbed by innumerable BLACK HOLES which are scattered uniformly throughout space.

NOTE: This explanation is still under construction.

 How many black holes would it take?
First, we'll determine the energy density that gives us the proper temperature:
U = a T4 n 3, T = 2.735° K, so U = 4.23 x 10-14 J / m.
That's 25 times smaller than the predicted energy density on the previous page.

Next, I'll determine what the absorption cross section of a black hole is by running a numerical simulation. The mass for a black hole I'll use is that of one found in the center of and average galaxy, about 10 8 solar masses or about 1038kg. Now this is a pretty arbitrary choice, and an important one. The size of a black hole increases linearly with it's mass. If I make it big enough, it won't take too many, with their correspondingly larger cross sections to suck up enough energy to make this explanation almost plausible. 108 solar masses is as large a black hole that seems to be common enough that the numbers required might just be plausible. Now for that cross section.

The Schwartzchild radius of a 108 solar mass black hole is the size of the earth's orbit, and astronomical unit, or about 1.5 x 1011 meters.