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Neutrino flavor oscillations with tensor network methods

Pooja Siwach

In close collaboration with

Michael Cervia

Amol Patwardhan

Baha Balantekin

Sue Coppersmith

Calvin Johnson

Sept. 3, 2022

PRD 105, 123025 (2022)

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Neutrinos in supernova (+ other denser media)

  • 99% of energy is carried away by neutrinos within 10s of seconds

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  • Dense interior provides the collective flavor oscillations due to neutrino-neutrino interaction

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Collective neutrino oscillations

Patwardhan et al, PRD (2019)

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Entanglement measure

Schmidt decomposition

RDM

Entanglement entropy

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Mean-field vs many-body

Cervia et al, PRD (2019)

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Tensor networks

“Let your boat of life be light, packed with only what you need…” – Jerome K. Jerome

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MPS & MPO

Schollwock, Ann. Phys. (2011)

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TDVP (time dependent variational principle)

  • Suitable for long-range interaction
  • Two-site TDVP is important for entanglement generation

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Global Subspace Expansion

Paeckel et al., Ann. Phys. (2019)

Yang and White, PRB (2020)

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Results

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Spectral splits

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Scaling of different methods

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What next?

Employing advanced processing units like GPUs, TPUs…

Improving the algorithms and devising new problem-oriented algorithms

New computational paradigms like quantum computing

Thanks