A brief introduction to observational entropy

Abstract

In the past several years, observational entropy has been developed as both a (time-dependent) quantum generalization of Boltzmann entropy, and as a rather general framework to encompass classical and quantum equilibrium and non-equilibrium coarse-grained entropy. In this paper we review the construction, interpretation, most important properties, and some applications of this framework. The treatment is self-contained and relatively pedagogical, aimed at a broad class of researchers.

arXiv commentReview of recent developments in observational entropy in isolated systems. 8+4 pages, 3 figures, 1 table

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Cited by in corpus (26)

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• Classicality, Markovianity and local detailed balance from pure state dynamics
• Observational entropy, coarse quantum states, and Petz recovery: information-theoretic properties and bounds
• Boltzmann entropy of a freely expanding quantum ideal gas
• Observational entropic study of Anderson localization
• Continuity bounds on observational entropy and measured relative entropies
• Emergence of a second law of thermodynamics in isolated quantum systems
• On the generic increase of observational entropy in isolated systems
• Measuring energy by measuring any other observable
• Comparative Microscopic Study of Entropies and their Production
• Quantifying Information Extraction using Generalized Quantum Measurements
• Observational entropy with general quantum priors
• Microscopic contributions to the entropy production at all times: From nonequilibrium steady states to global thermalization
• Emergent Time and Time Travel in Quantum Physics
• Kolmogorov complexity as intrinsic entropy of a pure state: Perspective from entanglement in free fermion systems
• Sample Complexity of Black Box Work Extraction
• Modeling the Past Hypothesis: A Mechanical Cosmology
• A New Census of the Universe's Entropy
• Evidence for simple "arrow of time functions" in closed chaotic quantum systems
• Target Space Entanglement in Quantum Mechanics of Fermions and Matrices
• Entropic partial orderings of quantum measurements
• Testing the Quantum of Entropy
• Typical Positivity of Nonequilibrium Entropy Production for Pure States
• Tight conic approximation of testing regions for quantum statistical models and measurements
• Macroscopicity and observational deficit in states, operations, and correlations
• Entropy of Quantum Measurements