Quantum dynamics in the self-consistent quadratic approximation
- URL: http://arxiv.org/abs/2403.11327v1
- Date: Sun, 17 Mar 2024 20:13:41 GMT
- Title: Quantum dynamics in the self-consistent quadratic approximation
- Authors: Frank Ernesto Quintela Rodriguez,
- Abstract summary: A self-consistent quadratic theory is presented to account for nonlinear contributions in quantum dynamics.
The dynamics is proven trace-preserving, with the Hamiltonian acting as a constant of motion for initial Gaussian states.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: A self-consistent quadratic theory is presented to account for nonlinear contributions in quantum dynamics. Evolution equations are shown to depend on higher-order gradients of the Hamiltonian, which are incorporated via their equations of motion or through perturbative calculations. The dynamics is proven trace-preserving, with the Hamiltonian acting as a constant of motion for initial Gaussian states. Nonlinear response functions are calculated perturbatively, and sufficient conditions are provided for the existence of their classical limit.
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