The cosmic microwave background (CMB, CMBR), in Big Bang cosmology, is electromagnetic radiation which is a remnant from an early stage of the universe, also known as "relic radiation". The CMB is ...

As the universe expanded, the material cooled, condensing after ~400,000 years into neutral atoms, freeing the cosmic microwave background (CMB). Fifty million years or so later, gravity drove the ...

This Cosmic Microwave Background Radiation (CMBR) is the conclusive evidence for the Big Bang theory. The 'temperature' of deep space has been measured as around 3K, not absolute zero, due to the ...