23 citations · 51 across the 8 of their papers we have counts for
8 papers
Polyanalytic Toeplitz operators: isomorphisms, symbolic calculus and approximation of Weyl operators
Johannes Keller, Franz Luef
We discuss an extension of Toeplitz quantization based on polyanalytic functions. We derive isomorphism theorem for polyanalytic Toeplitz operators between weighted Sobolev-Fock sp…
A Geometric Heat-Flow Theory of Lagrangian Coherent Structures
Daniel Karrasch, Johannes Keller
We consider Lagrangian coherent structures (LCSs) as the boundaries of material subsets whose advective evolution is metastable under weak diffusion. For their detection, we first…
The spectrogram expansion of Wigner functions
Johannes Keller
Wigner functions generically attain negative values and hence are not probability densities. We prove an asymptotic expansion of Wigner functions in terms of Hermite spectrograms,…
Quantum expectations via spectrograms
Johannes Keller, Caroline Lasser, Tomoki Ohsawa
We discuss a new phase space method for the computation of quantum expectation values in the high frequency regime. Instead of representing a wavefunction by its Wigner function, w…
A new Phase Space Density for Quantum Expectations
Johannes Keller, Caroline Lasser, Tomoki Ohsawa
We introduce a new density for the representation of quantum states on phase space. It is constructed as a weighted difference of two smooth probability densities using the Husimi…
An invariant class of wave packets for the Wigner transform
Helge Dietert, Johannes Keller, Stephanie Troppmann
Generalised Hagedorn wave packets appear as exact solutions of Schrödinger equations with quadratic, possibly complex, potential, and are given by a polynomial times a Gaussian. We…
Quasi-classical description of molecular dynamics based on Egorov's theorem
Johannes Keller, Caroline Lasser
Egorov's theorem on the classical propagation of quantum observables is related to prominent quasi-classical descriptions of quantum molecuar dynamics as the linearized semiclassic…
Propagation of Quantum Expectations with Husimi Functions
Johannes Keller, Caroline Lasser
We analyse the dynamics of expectation values of quantum observables for the time-dependent semiclassical Schrödinger equation. To benefit from the positivity of Husimi functions,…