Similar comments can be made about the cosmic microwave background.

We check that against the cosmic microwave background, and it seems to hold.

A related problem is the evenness of the microwave background.

This is far less than the 2.7 K produced by the cosmic microwave background.

Another reference frame is provided by the Cosmic microwave background.

That means they would already be exerting their influence by the time the microwave background was born.

It was even more difficult than detecting the microwave background.

The light which constitutes the cosmic microwave background comes from the surface of last scattering.

In 2003, observations of the cosmic microwave background confirmed this discovery.

The cosmic microwave background was initially thought to be isotropic-it's the same where ever you look.