Geometry of Quantum Statistical Inference
Abstract
An efficient geometric formulation of the problem of parameter estimation is developed, based on Hilbert space geometry. This theory, which allows for a transparent transition between classical and quantum statistical inference, is then applied to the analysis of exponential families of distributions (of relevance to statistical mechanics) and quantum mechanical evolutions. The extension to quantum theory is achieved by the introduction of a complex structure on the given real Hilbert space. We find a set of higher order corrections to the parameter estimation variance lower bound, which are potentially important in quantum mechanics, where these corrections appear as modifications to Heisenberg uncertainty relations for the determination of the parameter.
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The analytical formulas of the fidelity F(ρ0,ρτ) and the affinity A(ρ0,ρτ) for any pair of one-qubit states are given by Eqs. (A12) and (A13).
“where the analytical formulas of the fidelity Fðρ 0 ; ρ τ Þ and the affinity Aðρ 0 ; ρ τ Þ for any pair of one-qubit states ρ 0 and ρ τ are the following [29,73,74]:”
From Generalized Geometric Quantum Speed Limits (2016) · cites this paper as [73]
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- Authors
- Brody, D. C., & Hughston, L. P.
- Affiliations
- Imperial College London (GB)
- Venue
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Published
- 1996-09-30
- Volume
- 77
- Issue
- 14
- Pages
- 2851-2854
- ISSN
- 0031-9007 (ISSN-L)
- 1079-7114
- OpenAlex
- W1977587840
- Cited by
- 70
- References
- 9
- Citations by year
- 2026: 1 · 2025: 5 · 2024: 3 · 2022: 4 · 2021: 3 · 2020: 4 · 2019: 3 · 2018: 4 · 2017: 2 · 2016: 1 · 2013: 4 · 2012: 5
- FWCI
- 2.64
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Physical Review Letters (publishedVersion)
- PubMed (publishedVersion)
- Goldsmiths (University of London) (acceptedVersion)
- UCL Discovery (University College London) (submittedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Information and Cryptography
- Physical Sciences › Computer Science › Artificial Intelligence › Quantum Computing Algorithms and Architecture
- Keywords
- quantum statistical inference, parameter estimation, Hilbert space geometry, exponential family, complex structure, Cramer-Rao lower bound, higher-order corrections, uncertainty principle, quantum-to-classical transition
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