Light and Action

Деннис Габор

Hans-Otto Carmesin

In everyday life, in smartphones, we use electromagnetic waves for telecommunication. These waves propagate at the velocity of light. Is telecommunication at superluminal velocity (at ) possible? Einstein (1907) wrote that no action can travel faster than light, as such action would imply a causality violation. However, quantum physics includes actions that travel faster than light, see e. g. Einstein, Podolski and Rosen (1935). Accordingly, Einstein (1948) named such actions (at ) ‘spukhafte Fernwirkung’ or ‘spooky action at a distance’. But Aspect, Grangier and Roger (1982) provided such action at in experiments with pairs of entangled photons. While this experiment demonstrates the seeming transfer of information at , delayed-choice experiments do additionally demonstrate the seeming transport of energy and matter at , see Jaques (2008) and Manning et al. (2015). Do these actions at violate the principle of causality? Does quantum gravity escape causality violation, as Hobson, Efstathiou and Lasenby hope (2006, p. 346)? Can such action at be used in telecommunications and quantum computers? These questions are answered with help of the dynamics of volume in nature, the volume dynamics, VD, see Carmesin (2023a). The VD bridge general relativity and quantum physics. For these results, we provide a learning process, so that you can directly use the concept in your courses. The learning process has been tested in various learning groups, and experiences are reported.

Fam Le Kien, V. I. Balykin, K. Hakuta

We study the action of the force and torque induced by a guided light field on a cesium atom outside a nanofiber. We demonstrate that the evanescent light field in a circular fundamental guided mode can force the atom to rotate around the nanofiber for a macroscopic time. We find that, due to the action of the torque, the angular momentum of the atom increases with time.

Daniel F. Walls, Gerard J Milburn

A. V. Vysloukh, Vyacheslav A. Trofimov

The possibility of formation of several longitudinal kinks under the action of a collimated Gaussian light beam in a medium with absorptive cavityless optical bistability is demonstrated to be possible. The beam is essentially affected by diffraction. The domain formation is caused by the focusing of an annular beam into which the Gaussian beam is transformed due to nonlinear light absorption at small depths.