Three-Dimensional Low-Density Fermions in Planckian Limit: Entropy and Dynamics

Shao-Jian Jiang; Fei Zhou

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arXiv · 2301.12657

Three-Dimensional Low-Density Fermions in Planckian Limit: Entropy and Dynamics

Shao-Jian Jiang·Fei Zhou

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Abstract

In this Letter, we explore dynamics in a three-dimensional strongly interacting liquid. In quantum liquids discussed below, thermodynamic properties such as pressure and thermal energies are fully characterized by $s(T)$, the entropy density of the liquid (that is also directly proportional to the hydrodynamic viscosity). We obtain a universal fermion spectral function $A(\omega, {\bf k})$ that is distinctly specified by $\hbar / T$, a Planckian time scale. These phenomena can emerge in strongly interacting many-body states with a finite fermion density $\rho$ at temperatures $T^*$ where the chemical potential of fermions $\mu(\rho, T=T^*)$ approaches zero and can be thought as many-body simulations of certain aspects of Planckian dynamics.

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Shao-Jian Jiang, Fei Zhou. 2023-01-30. Three-Dimensional Low-Density Fermions in Planckian Limit: Entropy and Dynamics. https://arxiv.org/abs/2301.12657

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