Algorithmic Information Theory for Quantum State Tomography

Jincheng Zhang

Published Sep 5, 2026• 0 citations

Abstract

Quantum state tomography (QST) is a crucial technique for characterizing the state of a quantum system, often employed in quantum metrology, quantum communication, and fundamental quantum information science. However, QST inherently suffers from significant measurement redundancy and uncertainty, demanding a large number of measurements to achieve a desired level of accuracy. This work proposes a novel framework for QST leveraging concepts from algorithmic information theory, specifically Kolmogorov complexity, to rigorously quantify this uncertainty and redundancy. We introduce a tailored complexity measure for quantum states that allows for the design of measurement strategies optimized to minimize the number of required measurements while maintaining a specified accuracy. Our approach shifts the focus from purely statistical estimation to a fundamental information-theoretic analysis, offering a deeper understanding of the reconstruction problem and potentially leading to more efficient and robust QST protocols. The core claim is that applying Kolmogorov complexity provides a quantifiable metric for the inherent uncertainty within a quantum state, directly informing the development of improved estimation techniques. The mechanism involves defining and utilizing this complexity measure to guide the selection of measurement angles, ultimately reducing redundancy and improving the precision of state reconstruction.

DOI: 10.5281/zenodo.22339289

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