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arXiv · 1709.07613

SYK Model, Chaos and Conserved Charge

Ritabrata Bhattacharya·Subhroneel Chakrabarti·Dileep P. Jatkar·Arnab Kundu
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Abstract

We study the SYK model with complex fermions, in the presence of an all-to-all $q$-body interaction, with a non-vanishing chemical potential. We find that, in the large $q$ limit, this model can be solved exactly and the corresponding Lyapunov exponent can be obtained semi-analytically. The resulting Lyapunov exponent is a sensitive function of the chemical potential $μ$. Even when the coupling $J$, which corresponds to the disorder averaged values of the all to all fermion interaction, is large, values of $μ$ which are exponentially small compared to $J$ lead to suppression of the Lyapunov exponent.

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Ritabrata Bhattacharya, Subhroneel Chakrabarti, Dileep P. Jatkar, Arnab Kundu. 2017-10-09. SYK Model, Chaos and Conserved Charge. https://doi.org/10.1007/jhep11(2017)180

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