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DOE OSTI Β· 2938037

Quantum magic and computational complexity in the neutrino sector

Chernyshev, Ivan [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000182891991)Β·Robin, Caroline E. P. [University of Bielefeld (Germany); GSI-Helmholtzzentrum fur Schwerionenforschung, Darmstadt (Germany)] (ORCID:000000015487270X)Β·Savage, Martin J. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000165027106)
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Abstract

We consider the quantum magic in systems of dense neutrinos undergoing coherent flavor transformations, relevant for supernova and neutron-star binary mergers. Mapping the three-flavor-neutrino system to qutrits, the evolution of quantum magic is explored in the single scattering angle limit for a selection of initial tensor-product pure states for 𝑁 𝜈 ≀ 8 neutrinos. For |πœˆπ‘’βŸ© βŠ—π‘πœˆ initial states, the magic, as measured by the 𝛼 = 2 stabilizer Renyi entropy β„³ 2 , is found to decrease with radial distance from the neutrino sphere, reaching a value that lies below the maximum for tensor-product qutrit states. Further, the asymptotic magic per neutrino, β„³ 2 /𝑁 𝜈 , decreases with increasing 𝑁 𝜈 . In contrast, the magic evolving from states containing all three flavors reaches values only possible with entanglement, with the asymptotic β„³ 2 /𝑁 𝜈 increasing with 𝑁 𝜈 . These results highlight the connection between the complexity in simulating quantum physical systems and the parameters of the Standard Model.

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computational complexityneutrino oscillationsneutrinosnuclear astrophysicsnuclear matter in neutron starsquantum simulationqudits

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Chernyshev, Ivan [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000182891991), Robin, Caroline E. P. [University of Bielefeld (Germany); GSI-Helmholtzzentrum fur Schwerionenforschung, Darmstadt (Germany)] (ORCID:000000015487270X), Savage, Martin J. [Univ. of Washington, Seattle, WA (United States)] (ORCID:0000000165027106). 2025-06-04. Quantum magic and computational complexity in the neutrino sector. https://doi.org/10.1103/physrevresearch.7.023228

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