However, the universe also cools down, meaning that the average energy per particle is getting smaller with time.

Temperature is related to the average energy of a group of molecules.

By increasing T we increase the average energy of all the molecules.

It is often described as the average kinetic energy per molecule within a substance.

The perturbation causes the average energy of this state to increase by .

The electrons produced have an average energy of 5.7 keV.

However, the Universe also cools down, meaning that the average energy per particle gets smaller.

The average energy per degree-of-freedom increases, and that is a higher temperature.

We can use the average energy of the signal to find the final expression :

Therefore, the average energy of an electron is given by: