Workshop »Numerics, dynamics & physics«
Date and place
June 14th, 2024 @ KIT · Karlsruhe
Speakers
- Kurt Busch · Berlin (Germany)
- Caroline Lasser · Munich (Germany)
- Christian Lubich · Tübingen (Germany)
Scientific program
The talks will be held in the Fritz-Haller Lecture Hall (ground floor) in building 20.40 (Englerstr. 7). The lecture hall is located straight through the entrance hall coming into the building from the Englerstraße.
Friday, June 14th | |
---|---|
14:00 | Caroline Lasser · Observing Variational Gaussian Wave Packets Abstract: We discuss time-dependent Schrödinger equations with smooth electric and magnetic potentials. We analyze time-dependent variational approximation with a single nonlinearly parametrized Gaussian wave packet. The derived error estimates are joint work with S. Burkhard, B. Dörich and M. Hochbruck: They generalize established results on accuracy with respect to the $L^2$-norm and strongly improve what has been known with respect to observable accuracy. |
14:45 | Kurt Busch · Atom-Surface Interactions: Theory and Computations Abstract: When an atom is placed near a material body, it experiences quantum fluctuations of the electromagnetic field that are modified relative to those of vacuum. In turn, this leads to a number of quantum-fluctuation-induced effects that include modifications of spontaneous emission and near-field radiative transfer as well as the occurrence of fluctuation-induced forces such as Casimir, Casimir-Polder forces and quantum friction. The latter are of particular relevance for micro- and nano-electromechanical systems and atom-chips. In this talk, a path from basic physical principles to reliable quantitative computations of atom-surface interactions will be sketched where the emphasis will be on the Casimir-Polder force. Highly symmetric systems with simple material models lend themselves to semi-analytical solutions where the evaluation of poorly converging series greatly benefit from recent advances in summation techniques based modified discrete Laguerre polynomials. Complex geometries and material models require advanced Maxwell solvers that are capable of addressing the various underlying length and time scales. In particular, it is demonstrated that Discontinuous-Galerkin Time-Domain Maxwell solvers facilitate accurate computations for systems at finite temperatures and for spatially nonlocal materials. |
15:30 | Break |
16:00 | Christian Lubich · Transient Dynamics Under Structured Perturbations: Bridging Unstructured and Structured Pseudospectra Abstract: This talk is about numerics for problems of linear dynamics via nonlinear dynamics, with possible uses in physics. As is known, bounds of the resolvent of a matrix in the right complex half-plane yield bounds of solutions of homogeneous and inhomogeneous linear differential equations with this matrix. We ask two basic questions:
|
16:45 until 17:45 |
Get-together |
Contact
Get in touch with us via admin∂waves.kit.edu or contact directly one of the organizers below.