Work

Noncontextual Pauli Hamiltonians

Year: 2025

Type: article

Abstract: Contextuality is a key feature of quantum mechanics, and identification of noncontextual subtheories of quantum mechanics is of both fundamental and practical importance. Recently, noncontextual Pauli Hamiltonians have been defined in the setting of variational quantum algorithms. In this work we rigorously establish a number of properties of noncontextual Pauli Hamiltonians. We prove that these Hamiltonians can be composed of more Pauli operators than diagonal Hamiltonians. This establishes that noncontextual Hamiltonians are able to describe a greater number of physical interactions. We then show that the eigenspaces admit an efficient classical description. We analyze the eigenspace of these Hamiltonians and prove that for every eigenvalue there exists an associated eigenvector whose stabilizer rank scales linearly with the number of qubits. We prove that further structure in these Hamiltonians allow us to derive where degeneracies in the eigenspectrum can arise. We thus open the field to a new class of efficiently simulatable states.

Source: Journal of Physics A Mathematical and Theoretical

DOI: 10.1088/1751-8121/adf677

Authors: Alexis Ralli, Tim Weaving, Peter J Love

Institutions: Tufts University, University College London, Brookhaven National Laboratory

Language: English

Topic: Quantum Computing Algorithms and Architecture

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

Funder: Engineering and Physical Sciences Research Council

OpenAlex ID: W4413197165

FWCI:

Cites: 60

Cited by:

Related to: 10