dorsal/arxiv
View SchemaMicrocanonical distributions for quantum systems
| Authors | Dorje C Brody, Daniel W Hook, Lane P Hughston |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0506163 |
| URL | https://arxiv.org/abs/quant-ph/0506163 |
Abstract
The standard assumption for the equilibrium microcanonical state in quantum mechanics, that the system must be in one of the energy eigenstates, is weakened so as to allow superpositions of states. The weakened form of the microcanonical postulate thus asserts that all quantum states giving rise to the same energy expectation value must be realised with equal probability. The consequences that follow from this assertion are investigated. In particular, a closed-form expression for the density of states associated with any system having a nondegenerate energy spectrum is obtained. The result is applied to a variety of examples, for which the behaviour of the state density, as well as the relation between energy and temperature, are determined. Numerical studies indicate that the density of states converges to a distribution when the number of energy levels approaches infinity.
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"abstract": "The standard assumption for the equilibrium microcanonical state in quantum\nmechanics, that the system must be in one of the energy eigenstates, is\nweakened so as to allow superpositions of states. The weakened form of the\nmicrocanonical postulate thus asserts that all quantum states giving rise to\nthe same energy expectation value must be realised with equal probability. The\nconsequences that follow from this assertion are investigated. In particular, a\nclosed-form expression for the density of states associated with any system\nhaving a nondegenerate energy spectrum is obtained. The result is applied to a\nvariety of examples, for which the behaviour of the state density, as well as\nthe relation between energy and temperature, are determined. Numerical studies\nindicate that the density of states converges to a distribution when the number\nof energy levels approaches infinity.",
"arxiv_id": "quant-ph/0506163",
"authors": [
"Dorje C Brody",
"Daniel W Hook",
"Lane P Hughston"
],
"categories": [
"quant-ph"
],
"title": "Microcanonical distributions for quantum systems",
"url": "https://arxiv.org/abs/quant-ph/0506163"
},
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