Quantum mechanical derivation of ohm's law?

johnathon
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I'm watching MIT 8.02 electricity and magnetism () and the lecturer says that there is a derivation of ohm's law but it uses quantum mechanics which is outside the scope of the course. Does anybody know of this derivation and can point me to it? I searched around but can't find anything
 
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The linear relationship I~V (respectively j~E) can be derived from the classical Drude theory. This is what's usually called Ohm's Law.

What is not predicted correctly is the proportionality factor R (respectively ρ). See maybe http://en.wikipedia.org/wiki/Classical_and_quantum_conductivity.
 
johnathon said:
I'm watching MIT 8.02 electricity and magnetism () and the lecturer says that there is a derivation of ohm's law but it uses quantum mechanics which is outside the scope of the course. Does anybody know of this derivation and can point me to it? I searched around but can't find anything


the basic model for conduction is the drude model. this assumes that electrons behave like billiard balls. this is enough to prove ohms law. the quantum model is the drude-sommerfield model. here electrons behave like waves and scatter off impurity atoms. then there is a more advanced model call nearly free electron model. anyways the quantum theory successfully explains the temperature dependence of resistivity which the classical drude model is not able to . i would say not to bother with derivations, the important thing is to understand how conduction happens from the quantum mechanical perspective.
 
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physwizard said:
the basic model for conduction is the drude model. this assumes that electrons behave like billiard balls. this is enough to prove ohms law. the quantum model is the drude-sommerfield model. here electrons behave like waves and scatter off impurity atoms. then there is a more advanced model call nearly free electron model. anyways the quantum theory successfully explains the temperature dependence of resistivity which the classical drude model is not able to . i would say not to bother with derivations, the important thing is to understand how conduction happens from the quantum mechanical perspective.

So can ohm's law be derived from the nearly free electron model?
 
Interesting article on Ohm's law in the quantum scale - http://physicsworld.com/cws/article/news/48242
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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