15:00 – Eva Marie Greafe (Imperial)
Title: Quantum Theory, Complexification, and the Semi-Classical Limit
Abstract: The relation between quantum systems and their classical analogues is a subtle matter that has been investigated since the early days of quantum mechanics.
Today, we have at our disposal powerful mathematical tools that have resulted from the interplay of theoretical physics and pure mathematics to formulate in a precise way the semi-classical limit. The understanding of quantum classical correspondence is of importance (a) for the interpretation and practical understanding of quantum effects, and (b) as a basis of a variety of simulation methods for quantum spectra and dynamics. Recently, there has been a growing interest in so-called non Hermitian or “complexified” quantum theories. Applications include (i) decay, (ii) transport and scattering phenomena, (iii) dissipative systems, and (iv) PT-symmetric theories. In this talk I will present an overview of some of the issues and novelties arising in the investigation of the classical analogues of such “complexified” quantum theories, which give rise to phenomena that are of interest both from a mathematical and a physical perspective.
16:00 – Seb Guenneau (CNRS)
Title: Models of waves in structured media: Application to negative refraction and cloaking
Abstract: Negative refraction of light allows for sub-wavelength focusing effects through a slab lens. One may wonder whether Pendry’s perfect lens also has applications in other areas of physics. Using analogies between equations for surface electromagnetic and acoustic waves, we shall see that negative refraction can be achieved in the context of surface plasmons on a structured metal plate, water waves on a free surface, and flexural waves in structured plates. We shall also investigate cloaking effects, whereby a wave is smoothly detoured around a region on a free surface (in the contex of water waves) or a plate (in the context of plasmonics and elastodynamics). Finally, we shall unveil some recent developments in thermal lensing and cloaking.