Unitary Evolutions Sourced By Interacting Quantum Memories: Closed
Quantum Systems Directing Themselves Using Their State Histories
- URL: http://arxiv.org/abs/2201.05583v3
- Date: Fri, 5 May 2023 07:48:07 GMT
- Title: Unitary Evolutions Sourced By Interacting Quantum Memories: Closed
Quantum Systems Directing Themselves Using Their State Histories
- Authors: Alireza Tavanfar, Aliasghar Parvizi, Marco Pezzutto
- Abstract summary: We show that momentary choices of the system's memories interact in order to source the internal interactions and unitary time evolutions of the system.
In a closed system of the kind, the unitary evolution operator is updated, moment by moment, by being remade out of the system's experience', that is, its quantum state history.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We propose, formulate and examine novel quantum systems and behavioral phases
in which momentary choices of the system's memories interact in order to source
the internal interactions and unitary time evolutions of the system. In a
closed system of the kind, the unitary evolution operator is updated, moment by
moment, by being remade out of the system's `experience', that is, its quantum
state history. The `Quantum Memory Made' Hamiltonians (QMM-Hs) which generate
these unitary evolutions are Hermitian nonlocal-in-time operators composed of
arbitrarily-chosen past-until-present density operators of the closed system or
its arbitrary subsystems. The time evolutions of the kind are described by
novel nonlocal nonlinear von Neumann and Schr\"odinger equations. We establish
that nontrivial Purely-QMM unitary evolutions are `Robustly Non-Markovian',
meaning that the maximum temporal distances between the chosen quantum memories
must exceed finite lower bounds which are set by the interaction couplings.
After general formulation and considerations, we focus on the
sufficiently-involved task of obtaining and classifying behavioral phases of
one-qubit pure-state evolutions generated by first-to-third order polynomial
QMM-Hs made out of one, two and three quantum memories. The behavioral
attractors resulted from QMM-Hs are characterized and classified using QMM
two-point-function observables as the natural probes, upon combining analytical
methods with extensive numerical analyses. The QMM phase diagrams are shown to
be outstandingly rich, having diverse classes of unprecedented unitary
evolutions with physically remarkable behaviors. Moreover, we show that QMM
interactions cause novel purely-internal dynamical phase transitions. Finally,
we suggest independent fundamental and applied domains where the proposed
`Experience Centric' Unitary Evolutions can be applied natuarlly and
advantageously.
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