the paper deal with non-commutative geometry. the notion of quantumspheres was introduced by podles. here we define the quantum hermitianmetric on the quantum spaces and find it for the quantum spheres.

The paper deal with non-commutative geometry. The notion of quantumspheres was introduced by podles. Here we define the quantum hermitianmetric on the quantum spaces and find it for the quantum spheres.

Acausal features of quantum electrodynamic processes are discussed. While these processes are not present for the classical electrodynamic theory, in the quantum electrodynamic theory, acausal processes are well known to exist. For example, any Feynman diagram with a " loop " in space-time describes a " particle " which may move forward in time or backward in time or in space-like directions. T...

The one-electron quantum-electrodynamic corrections to the magnetic-dipole transition amplitude between the fine-structure levels (1s2s2p) P3/2 − P1/2 in boronlike ions are calculated to all orders in αZ. The results obtained serve for improving the theoretical accuracy of the lifetime of the (1s2s2p) P3/2 level in boronlike argon. PACS. 31.30.Jv Relativistic and quantum electrodynamic effects ...

Precision spectroscopy of simple atomic systems has refined our understanding of the fundamental laws of quantum physics. In particular, helium spectroscopy has played a crucial role in describing two-electron interactions, determining the fine-structure constant and extracting the size of the helium nucleus. Here we present a measurement of the doubly forbidden 1557-nanometer transition connec...

In this paper, we review some recent cavity quantum electrodynamic (CQED) experiments with single quantum dot exciton coupled to photonic crystal cavities, performed in our group. We show how the coupled quantumdot/cavity system can be used to modulate light with at a very fundamental level with very low power and discuss some applications of these low power modulators.

A definition is given and the physical meaning of quantum transformations of a non-commutative configuration space (quantum group coactions) is discussed. It is shown that non-commutative coordinates which are transformed by quantum groups are the natural generalization of the notion of a tensor operator for usual groups and that the quantum group coactions induce semigroups of transformations ...

A non–commutative analogue of the classical differential forms is constructed on the phase–space of an arbitrary quantum system. The non– commutative forms are universal and are related to the quantum mechanical dynamics in the same way as the classical forms are related to classical dynamics. They are constructed by applying the Weyl–Wigner symbol map to the differential envelope of the linear...