China
Africa
Explore chapters and articles related to this topic
Energy Rehabilitation: Regeneration and Recuperation
Published in Alexander V. Dimitrov, Introduction to Energy Technologies for Efficient Power Generation, 2017
It will increase with the increase in the temperature T of the photon “gas.” It is found that with temperature decreasing photons leave the high-frequency orbitals and pass to low-frequency ones while the distribution function takes another form.
Pre-Born–Oppenheimer molecular structure theory
Published in Molecular Physics, 2019
It is interesting to note that important molecular properties (shape, handedness, atomic labels) break the fundamental symmetries of an isolated quantum system: the rotational and inversion symmetry, as well as the indistinguishability of identical particles. It remains a task to explore on a detailed microscopic level how and why these broken-symmetry states become pointer states of a molecular system. Shape. Following the pioneering studies which have identified pointer states and confirmed their stability upon translational localisation [126–128] Ref. [129] provides a detailed account of the rotational decoherence of mesoscopic objects induced by a photon-gas environment or massive particles in thermal equilibrium. The qualitative conclusions are similar for the two different environments, but there are differences in the estimated decoherence time and its temperature dependence differ for the two environments. Orientational localisation of the mesoscopic ellipsoid takes place only if there are at least two directions for which the electric polarisabilities are different, and coherence is suppressed exponentially with the angular distance between two orientations.Handedness. As to the chirality of molecules, the superselection phenomenon has been demonstrated in Ref. [130] by using a master equation [131] which describes the incoherent dynamics of the molecular state in the presence of the scattering of a lighter, thermalised background gas. Experimental conditions are predicted under which the tunnelling dynamics is suppressed between the left and right-handed configurations of DS.Individual labelling of the atomic nuclei. Concerning the distinguishability of atomic nuclei, it remains a challenge to work out the detailed theoretical equations and to estimate the experimental conditions under which the individual labelling of quantum mechanically identical atomic nuclei (e.g. protons) emerges.