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I was reading about black body radiation on Wikipedia. In the explanation section, it says:

"All normal (baryonic) matter emits electromagnetic radiation when it has a temperature above absolute zero. The radiation represents a conversion of a body's thermal energy into electromagnetic energy, and is therefore called thermal radiation. It is a spontaneous process of radiative distribution of entropy."

Can somebody explain the last lines?

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Entropy in its statistical mechanics form can be defined

For a classical system (i.e., a collection of classical particles) with a discrete set of microstates, if E_i is the energy of microstate i, and p_i is the probability that it occurs during the system's fluctuations, then the entropy of the system is:

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The macroscopic state of a system is defined by a distribution on the microstates

At the quantum mechanical level, which is the regime of black body radiation, the number of microstates are the different probabilistic arrangements of all the elements in the closed system, "body + radiation"

Thus the sentence "radiative distribution of entropy" I believe refers to the continuous increase in entropy since each radiated photon adds microstates in the sum and increases the entropy.

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