13 papers
Integrable curl-force Hamiltonians: bi-Hamiltonian structure, separability, and periodic orbits
Alexander Felski, Andreas Fring
We investigate Hamiltonian curl-force systems with indefinite kinetic energy. We first reconsider Berry's polynomial Hamiltonian curl-force model, whose numerically observed closed…
Driving collective RPA modes by a time-dependent Dyson map
Andreas Fring, Marta Reboiro
We study a time-dependent non-Hermitian generalisation of the Schütte-Da~Providência model describing a bosonic mode coupled to collective particle-hole excitations. Using a time…
Hidden symmetry and Jordan chains in a resonant ghostly three-dimensional model
Andreas Fring, Ian Marquette
We investigate a three-dimensional ghostly Hamiltonian realisation of the fully degenerate resonant sixth-order Pais-Uhlenbeck oscillator. On the classical level, the phase-space f…
Lie symmetries and ghost-free representations of the Pais-Uhlenbeck model
Alexander Felski, Andreas Fring, Bethan Turner
We investigate the Pais-Uhlenbeck (PU) model, a paradigmatic example of a higher time-derivative theory, by identifying the Lie symmetries of its associated fourth-order dynamical…
Bounded Dyson maps and cavity-driven transitions in a time-dependent non-Hermitian spin-boson model
Andreas Fring, Marta Reboiro
We study a time-dependent non-Hermitian extension of the Schütte-Da Providência spin-boson Hamiltonian with complex couplings. A time-dependent Dyson map relates the model to a Her…
Quantum-classical diagnostics and Bohmian inequivalence for higher time-derivative Hamiltonians
Sanjib Dey, Andreas Fring
We develop a Bohmian analysis of a two-dimensional ghost Hamiltonian and its mapping to the degenerate Pais-Uhlenbeck model. Using Gaussian wavepackets, we derive the corresponding…