56 citations · 99 across the 7 of their papers we have counts for
7 papers
Explicit finite-time illustration of improper unitary evolution for the Klein--Gordon field in de Sitter space
William T. Emond, Christian Käding, Peter Millington
It is known that quantum field theories in curved spacetime suffer from a number of pathologies, including the inability to relate states on different spatial slices by proper unit…
Directly computing Wigner functions for open quantum systems
Nick Huggett, Christian Käding, Mario Pitschmann +1
The Wigner function is a well-known phase space distribution function with many applications in quantum mechanics. In this article, we consider an open quantum system consisting of…
Density matrices in quantum field theory: Non-Markovianity, path integrals and master equations
Christian Käding, Mario Pitschmann
Density matrices are powerful mathematical tools for the description of closed and open quantum systems. Recently, methods for the direct computation of density matrix elements in…
Dilaton Solutions for Laboratory Constraints and Lunar Laser Ranging
Philippe Brax, Hauke Fischer, Christian Käding +1
We derive approximate analytical solutions to the environment-dependent dilaton field theory equations in the presence of a one or two mirror system or a sphere. The one-dimensiona…
Astro- and Quantum Physical Tests of Screened Scalar Fields
Christian Käding
In general, modified gravity theories are modifications or extensions of Einstein's general relativity. Some of them give rise to additional scalar degrees of freedom in Nature. If…
Symmetron Scalar Fields: Modified Gravity, Dark Matter or Both?
Clare Burrage, Edmund J. Copeland, Christian Käding +1
Scalar fields coupled to gravity through the Ricci scalar have been considered both as dark matter candidates and as a possible modified gravity explanation for galactic dynamics.…
Quantum simulation of dark energy candidates
Daniel Hartley, Christian Käding, Richard Howl +1
Additional scalar fields from scalar-tensor, modified gravity or higher dimensional theories beyond general relativity may account for dark energy and the accelerating expansion of…