Consider a gas of atoms that might serve as a laser medium but that is inequilibrium, With no population inversions. A photon gas coexists with the atoms. Woulda photon whose energy is precisely the differencebetween two atomic energy states be more likely to be absorbed or to induce a stimulated emission or neither? We expect that inequilibrium the number. of atomsat different levels and the number of photons of a given energy should be stable. Is your answer compactible?

A photon whose energy is exactly equal to the difference between two atomic energy levels is more likely to be absorbed in a scenario where an atom gas coexists with a photon gas in equilibrium with no population inversions.The number of atoms in certain energy states and the number of photons with certain energies that are in equilibrium are both stable. In equilibrium where the number of atoms and photons are stable, the total absorption rate$R_{abs}$is equal to the total emission rate$R_{emission.}$since there are two types of possible emissions namely, spontaneous emission with rate$R_{spon,}$, and stimulated emission with rate$R_{stim,}$and the total emission rate must be:

$R_{emission}=R_{stim}+R_{spon.}$

Then the absorption rate$R_{abs}$is greater than the separate emission rates:

$R_{abs}>R_{stim},R_{spon}$

Causing the photon to be more likely absorbed. Thus, our answer is compatible.