Quantum speed limit and stability of coherent states in quantum gravity

• URL: http://arxiv.org/abs/2112.01597v2
• Date: Tue, 21 Jun 2022 13:18:20 GMT
• Title: Quantum speed limit and stability of coherent states in quantum gravity
• Authors: Klaus Liegener, {\L}ukasz Rudnicki
• Abstract summary: We investigate the dynamical properties of coherent states for Loop Quantum Gravity. The Quantum Speed Limit is adapted to Quantum Gravity, yielding consistency checks for any proposal of stable families of states. We report the variance of this constraint evaluated on a family of coherent states showing that, for short times, this family passes the Quantum Speed Limit test.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Utilizing the program of expectation values in coherent states and its recently developed algorithmic tools, this letter investigates the dynamical properties of cosmological coherent states for Loop Quantum Gravity. To this end, the Quantum Speed Limit is adapted to Quantum Gravity, yielding necessary consistency checks for any proposal of stable families of states. To showcase the strength of the developed tools, they are applied to a prominent model: the Euclidean part of the quantum scalar constraint. We report the variance of this constraint evaluated on a family of coherent states showing that, for short times, this family passes the Quantum Speed Limit test, allowing the transition from one coherent state to another one.

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