English

Quantum tomography from the evolution of a single expectation

Mathematical Physics 2025-02-19 v2 math.MP Quantum Physics

Abstract

We investigate the possibility of performing full quantum tomography based on the homogeneous time evolution of a single expectation value. Remarkably, every non-trivial binary measurement evolved by any quantum channel, except for a null set, in principle enables full quantum state tomography. We show that this remains true when restricted to Lindblad semigroups, although unitary evolution -- even with added simply depolarizing noise -- is insufficient beyond the qubit case, highlighting the necessity of non-trivial noise. We establish an analog of Takens' embedding theorem for quantum channels, which incorporates prior information into the framework. We also provide estimation bounds for finite statistics and analyze the feasibility of recovering an infinite time series of expectation values from a finite one using only spectral properties of the evolution.

Keywords

Cite

@article{arxiv.2501.10118,
  title  = {Quantum tomography from the evolution of a single expectation},
  author = {Hjalmar Rall and Michael M. Wolf},
  journal= {arXiv preprint arXiv:2501.10118},
  year   = {2025}
}

Comments

23 pages, 3 figures, references updated

R2 v1 2026-06-28T21:09:12.903Z