how to calculate the temperature of cmb over time ?

[stephaneww]

all is in tthe title

 

thank you very much for your answers

[swansont]

The temperature drops because the wavelength increases, in proportion to the expansion of the universe. Wien's law connects the wavelength with a temperature.

http://www.phy.duke.edu/~kolena/cmb.htm

http://www.cv.nrao.edu/course/astr534/CMB.html

[stephaneww]

Oh it is good !!!

 

thank you