Maybe it is just me, but I don't find entropy to be particularly useful in explaining why things happen.frankchen said:any isolated macroscopic system, like a large group of atoms, always tends to reach a state that has the maxium entropy. if the electrons in this group of atoms are excited, they will give out their energy so that more degrees of freedom are activated, hence the entropy of the whole system increase. that's why spontaneous emission happens, is that right?
The thermodynamic approach to spontaneous emission is a theoretical framework used to understand the spontaneous emission of photons from an excited atom or molecule. It is based on principles of thermodynamics and statistical mechanics.
According to the thermodynamic approach, spontaneous emission occurs when an excited atom or molecule releases excess energy in the form of photons to reach a lower energy state. This process is governed by thermodynamic principles such as the increase of entropy and the decrease of free energy.
The key assumptions of the thermodynamic approach include the existence of a thermal equilibrium between the atom or molecule and its surroundings, and the validity of the Boltzmann distribution for the population of energy levels. It also assumes that the emission process is a random and irreversible one.
The thermodynamic approach differs from other models, such as the quantum mechanical approach, in that it takes into account the effects of the surroundings on the emission process. It also provides a macroscopic description of the emission process, whereas other models focus on the microscopic behavior of individual particles.
The thermodynamic approach has practical applications in fields such as laser technology, where it is used to optimize the efficiency of spontaneous emission processes. It also has applications in astrophysics, where it is used to understand the emission of radiation from stars and other celestial objects.