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  • Letter
  • Open Access

Dynamics of the density cube

Nabin Bhatta*, Djordje Minic†, and Tatsu Takeuchi‡

  • Center for Neutrino Physics, Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA

  • *Contact author: nabinb@vt.edu
  • †Contact author: dminic@vt.edu
  • ‡Contact author: takeuchi@vt.edu
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APS Open Sci. 1, L000165 – Published 8 October, 2026

DOI: https://doi.org/10.1103/bn2b-jgll

Abstract

Density cube theory extends the canonical quantum density matrix ρij with the addition of an extra index to ρijk. The elements of the density cube with two different indices, ρiij and ρijj, correspond to the real and imaginary parts of the off-diagonal element ρij of the density matrix and describe double-path interference, while those with three different indices describe noncanonical triple-path interference. In this Letter, we propose an equation of motion for the density cube, obtained from the quantization of ternary Nambu dynamics, and find that pairs of triple-path interferences oscillate into each other.

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References (42)

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APS Open Sci. 1, L000165– Published 8 October, 2026
Vol. 1
  • Received 6 June 2026
  • Accepted 17 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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