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A universal bound on Quantum Chaos from Random Matrix Theory

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 نشر من قبل Sayantan Choudhury
 تاريخ النشر 2018
  مجال البحث فيزياء
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In this article, using the principles of Random Matrix Theory (RMT), we give a measure of quantum chaos by quantifying Spectral From Factor (SFF) appearing from the computation of two-point Out of Time Order Correlation function (OTOC) expressed in terms of square of the commutator bracket of quantum operators which are separated in time. We also provide a strict model independent bound on the measure of quantum chaos, $-1/N(1-1/pi)leq {bf SFF}leq 0$ and $0leq {bf SFF}leq 1/pi N$, valid for thermal systems with a large and small number of degrees of freedom respectively. Based on the appropriate physical arguments we give a precise mathematical derivation to establish this alternative strict bound of quantum chaos.



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