Entropy of Quantum States
| Autor: | Giovanni Gramegna, Arturo Konderak, Paolo Facchi |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Density matrix
Pure mathematics operator algebra Science QC1-999 General Physics and Astronomy FOS: Physical sciences Von Neumann entropy Astrophysics 01 natural sciences Article Entropy (classical thermodynamics) symbols.namesake Quantum state 0103 physical sciences 010306 general physics Quantum statistical mechanics Mathematical Physics Mathematics Quantum Physics 010308 nuclear & particles physics Physics Observable Mathematical Physics (math-ph) QB460-466 quantum statistical mechanics n/a Operator algebra symbols Quantum Physics (quant-ph) quantum entropy Von Neumann architecture |
| Zdroj: | Entropy, Vol 23, Iss 645, p 645 (2021) Entropy Volume 23 Issue 6 |
| ISSN: | 1099-4300 |
| Popis: | Given the algebra of observables of a quantum system subject to selection rules, a state can be represented by different density matrices. As a result, different von Neumann entropies can be associated with the same state. Motivated by a minimality property of the von Neumann entropy of a density matrix with respect to its possible decompositions into pure states, we give a purely algebraic definition of entropy for states of an algebra of observables, thus solving the above ambiguity. The entropy so defined satisfies all the desirable thermodynamic properties, and reduces to the von Neumann entropy in the quantum mechanical case. Moreover, it can be shown to be equal to the von Neumann entropy of the unique representative density matrix belonging to the operator algebra of a multiplicity-free Hilbert-space representation. 20 pages, 2 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|