A Bose–Einstein condensate represents the most ‘classical’ form of a matter wave, just as an optical laser emits the most classical form of an electromagnetic wave. Nevertheless, the matter wave field has a quantized structure owing to the granularity of the discrete underlying atoms. Although such a field is usually assumed to be intrinsically stable (apart from incoherent loss processes), this is no longer true when the condensate is in a coherent superposition of different atom number states1,2,3,4,5,6. For example, in a Bose–Einstein condensate confined by a three-dimensional optical lattice, each potential well can be prepared in a coherent superposition of different atom number states, with constant relative phases between neighbouring lattice sites. It is then natural to ask how the individual matter wave fields and their relative phases evolve. Here we use such a set-up to investigate these questions experimentally, observing that the matter wave field of the Bose–Einstein condensate undergoes a periodic series of collapses and revivals; this behaviour is directly demonstrated in the dynamical evolution of the multiple matter wave interference pattern. We attribute the oscillations to the quantized structure of the matter wave field and the collisions between individual atoms.

Collapse and revival of the matter wave field of a Bose–Einstein condensate

Summary: Infection of humans with the nematode worm parasite Anisakis simplex was first described in the 1960s in association with the consumption of raw or undercooked fish During the 1990s it was realized that even the ingestion of dead worms in food fish can cause severe hypersensitivity reactions, that these may be more prevalent than infection itself, and that this outcome could be associated with food preparations previously considered safe Not only may allergic symptoms arise from infection by the parasites (“gastroallergic anisakiasis”), but true anaphylactic reactions can also occur following exposure to allergens from dead worms by food-borne, airborne, or skin contact routes This review discusses A simplex pathogenesis in humans, covering immune hypersensitivity reactions both in the context of a living infection and in terms of exposure to its allergens by other routes Over the last 20 years, several studies have concentrated on A simplex antigen characterization and innate as well as adaptive immune response to this parasite Molecular characterization of Anisakis allergens and isolation of their encoding cDNAs is now an active field of research that should provide improved diagnostic tools in addition to tools with which to enhance our understanding of pathogenesis and controversial aspects of A simplex allergy We also discuss the potential relevance of parasite products such as allergens, proteinases, and proteinase inhibitors and the activation of basophils, eosinophils, and mast cells in the induction of A simplex-related immune hypersensitivity states induced by exposure to the parasite, dead or alive

Anisakis simplex: from Obscure Infectious Worm to Inducer of Immune Hypersensitivity

Optimization Methods for Asteroid Lightcurve Inversion: I. Shape Determination

Photometric Survey of Binary Near-Earth Asteroids

http://www.asu.cas.cz/~ppravec/bindyn1.pdf

Binary asteroid population 1. Angular momentum content

The Near-Earth Objects Follow-Up Program: First Results

Extends the Feynman-Kac formula to the case of imaginary time Schrodinger equations (heat equations) for multicomponent wavefunctions. The approach covers in particular the usual Pauli equation for a spin-1/2 particle in an arbitrary magnetic field. The formula contains, besides the expectation with respect to a Wiener process in ordinary space, an expectation with respect to a jump process over the discrete indices describing the internal degrees of freedom. To illustrate the method the authors evaluate the formula in some special cases and they derive also various inequalities. A detailed comparison is made with a recent work by Gaveau and Vauthier (1981).

Probabilistic solution of Pauli type equations

Asteroid 243 Ida: Groundbased Photometry and a Pre-Galileo Physical Model

The authors develop the stochastic mechanics of a non-relativistic quantum particle with spin 1/2 in a possibly inhomogeneous magnetic field. They do not make any assumption about the inner structure of the particle, and treat spin components as discrete random variables.

A stochastic description of a spin-1/2 particle in a magnetic field

The authors develop the stochastic mechanics of a Dirac particle interacting with an arbitrary external electromagnetic field in two-dimensional Minkowski space. Their construction provides a consistent stochastic interpretation of solutions of the true (real time) Dirac equation and, in particular, gives a stochastic description of the zitterbewegung.

https://iopscience.iop.org/article/10.1088/0305-4470/19/6/017/pdf

G. De Angelis

Papers

The Near-Earth Objects Follow-Up Program: First Results

Probabilistic solution of Pauli type equations

Asteroid 243 Ida: Groundbased Photometry and a Pre-Galileo Physical Model

A stochastic description of a spin-1/2 particle in a magnetic field

Stochastic mechanics of a Dirac particle in two spacetime dimensions