Calculating the quantum Fisher information via the truncated Wigner method

Quantum Physics [Submitted on 31 Mar 2026] Calculating the quantum Fisher information via the truncated Wigner method Thakur G. M. Hiranandani, Joseph J. Hope, Simon A. Haine In this work, we propose new methods of parameter estimation using stochastic sampling quantum phase-space simulations. We show that it is possible to compute the quantum Fisher information (QFI) from semiclassical stochastic samples using the Truncated Wigner Approximation (TWA). This method extends the class of quantum systems whose fundamental sensitivity limit can be computed efficiently to any system that can be modelled using the TWA, allowing the analysis of more meteorologically useful quantum states. We illustrate this approach with examples, including a system that evolves outside the spin-squeezing regime, where the method of moments fails. Comments: 8 pages, 5 figures Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2603.29196 [quant-ph]   (or arXiv:2603.29196v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2603.29196 Focus to learn more Submission history From: Simon Haine [view email] [v1] Tue, 31 Mar 2026 03:03:28 UTC (595 KB) Access Paper: view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-03 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)