Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: EvaH on 15/04/2020 16:56:45

Title: Is an electron's motion affected by entropy?
Post by: EvaH on 15/04/2020 16:56:45

Bruce wants to know:

Why isn't the electron's motion affected by entropy? Will atoms eventually wear out?

Can you help?

Title: Re: Is an electron's motion affected by entropy?
Post by: chiralSPO on 15/04/2020 17:18:37

Yes, electrons obey rules of entropy just like everything else does.

BUT!!!

The "motion" of an electron in atomic (and molecular) orbitals is not true motion, and cannot lose energy through friction or cyclotron radiation or any other means that would apply to macroscopic models of these tiny systems.

Some things to look at:
https://en.wikipedia.org/wiki/Entropy
https://en.wikipedia.org/wiki/Zero-point_energy
https://en.wikipedia.org/wiki/Atomic_orbital
https://en.wikipedia.org/wiki/Quantum_indeterminacy

Title: Re: Is an electron's motion affected by entropy?
Post by: evan_au on 15/04/2020 21:49:28

Quote from: OP

Why isn't the electron's motion affected by entropy?

The band structure of electron energy follows the principles of entropy, as well as quantum principles such as the Pauli Exclusion Principle.

This band structure is important in electrical (and thermal) conduction in metals and semiconductors.
- The Pauli Exclusion Principle says that no two electrons can be in the same quantum state
- So the specific electron energy levels that you see in isolated atoms gets "smeared out" into a wide band in the solid state
- But even then, the electrons tend to fall into the lowest energy that is available to them.
- The few electrons that are at higher energy levels are kicked there by thermal or radiation effects, but they tend to fall back to the lowest available energy fairly quickly

See: https://en.wikipedia.org/wiki/Valence_and_conduction_bands