Chaos and complexity by design
Oct 16, 2016
77 pages
Published in:
- JHEP 04 (2017) 121
- Published: Apr 20, 2017
e-Print:
- 1610.04903 [quant-ph]
View in:
Citations per year
Abstract: (Springer)
We study the relationship between quantum chaos and pseudorandomness by developing probes of unitary design. A natural probe of randomness is the “frame poten-tial,” which is minimized by unitary k-designs and measures the 2-norm distance between the Haar random unitary ensemble and another ensemble. A natural probe of quantum chaos is out-of-time-order (OTO) four-point correlation functions. We show that the norm squared of a generalization of out-of-time-order 2k-point correlators is proportional to the kth frame potential, providing a quantitative connection between chaos and pseudorandomness. Additionally, we prove that these 2k-point correlators for Pauli operators completely determine the k-fold channel of an ensemble of unitary operators. Finally, we use a counting argument to obtain a lower bound on the quantum circuit complexity in terms of the frame potential. This provides a direct link between chaos, complexity, and randomness.Note:
- 46+many pages, and all the figures too. v2: the director's cut -- more jokes, less typos
- AdS-CFT Correspondence
- Gauge-gravity correspondence
- Random Systems
- Holography and condensed matter physics (AdS/CMT)
- unitarity: operator
- chaos
- correlation function
References(96)
Figures(15)
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- [3]
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- [5]
- [6]
- [7]
- [8]
- [8]
- [9]
- [9]
- [10]
- [11]
- [12]
- [13]
- [14]
- [15]
- [16]
- [17]
- [18]
- [19]
- [20]
- [21]
- [22]
- [23]