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arXiv · 2606.02421

Dynamics of the Density Cube

Nabin Bhatta·Djordje Minic·Tatsu Takeuchi
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Abstract

Density cube theory extends the canonical quantum density matrix $\rho_{ij}$ with the addition of an extra index to $\rho_{ijk}$. The elements of the density cube with two different indices, $\rho_{iij}$ and $\rho_{ijj}$, correspond to the real and imaginary parts of the off-diagonal element $\rho_{ij}$ of the density matrix and describe double-path interference, while those with three different indices describe non-canonical 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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Nabin Bhatta, Djordje Minic, Tatsu Takeuchi. 2026-06-01. Dynamics of the Density Cube. https://arxiv.org/abs/2606.02421

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