Non-Hamiltonian commutators in quantum mechanics

Non-Hamiltonian commutators in quantum mechanics.

The symplectic structure of quantum commutators is first unveiled and then exploited to describe generalized non-Hamiltonian brackets in quantum mechanics. It is easily recognized that quantum-classical systems are described by a particular realization of such a bracket. In light of previous work, this paper explains a unified approach to classical and quantum-classical non-Hamiltonian dynamics...

Positive Commutators in Non-Equilibrium Quantum Statistical Mechanics

The method of positive commutators, developed for zero temperature problems over the last twenty years, has been powering progress in the spectral analysis of Hamiltonians in quantum mechanics. We extend this method to positive temperatures, i.e. to non-equilibrium quantum statistical mechanics. We use the positive commutator technique to give an alternative proof of a fundamental property of l...

Hamiltonian Formalism in Quantum Mechanics

To Vladimir Igorevich Arnol'd with admiration, on occasion of his 60 th birthday. Abstract Heisenberg motion equations in Quantum mechanics can be put into the Hamilton form. The difference between the commutator and its principal part, the Poisson bracket, can be accounted for exactly. Canonical transformations in Quantum mechanics are not, or at least not what they appear to be; their propert...

Minimal length in Quantum Mechanics and non-Hermitian Hamiltonian systems

Relativistic non-Hamiltonian mechanics

Relativistic particle subjected to a general four-force is considered as a nonholonomic system. The nonholonomic constraint in fourdimensional space–time represents the relativistic invariance by the equation for four-velocity ulu + c = 0, where c is the speed of light in vacuum. In the general case, four-forces are non-potential, and the relativistic particle is a non-Hamiltonian system in fou...