Abelian geometric phase for a Dirac neutral particle in a Lorentz symmetry violation environment

We introduce a new term into the Dirac equation based on the Lorentz symmetry violation background in order to make a theoretical description of the relativistic quantum dynamics of a spin-half neutral particle, where the wave function of the neutral particle acquires a relativistic Abelian quantum phase given by the interaction between a fixed time-like 4-vector background and crossed electric and magnetic fields, which is analogous to the geometric phase obtained by Wei \textit{et al} [H. Wei, R. Han and X. Wei, Phys. Rev. Lett. \textbf{75}, 2071 (1995)] for a spinless neutral particle with an induced electric dipole moment. We also discuss the flux dependence of energy levels of bound states analogous to the Aharonov-Bohm effect for bound states.Comment: 16 pages, no figure

Modelling anaerobic digestion during temperature and load variations

Experimental results and simulations based on the Anaerobic Digestion Model No.1 (ADM1) with temperature effects on kinetics were used to evaluate rate limiting steps in sludge bed anaerobic digestion (AD) during load and temperature variations. Simulations were carried out in Aquasim. The model is compared to data from a pilot experiment in a 220 liter AD sludge bed reactor treating diary manure for 16 months of various loads; 0–13 kg COD L−1 d−1 and various temperatures; 25°C, 30°C and 35°C. Methane and CO2 production were monitored on-line while soluble and particulate organic carbon, pH and volatile fatty acids were measured on regularly collected inlet and effluent samples. Simulated overall soluble and particulate organic carbon removal, methane and CO2 production, pH and acetate are close to measured values while propionate is underestimated during some transitions. The fit is mainly sensitive to the composition of the feed in terms of relative amounts of lipids, proteins and carbohydrates especially at simultaneously high load and low temperature. During such conditions, the model predicts accumulation of long chained fatty acids (LCFA), suggesting that the degradation of LCFA is the rate-limiting step at low temperatures. This effect is not explained by reduced LCFA solubility at lower temperature. The model predicts that sludge bed AD efficiency on substrates with little or no LCFA is independent of temperature between 25°C and 35°C while LCFA degradation is favoured by higher temperature.The project was supported by the Norwegian Agricultural Agency, Innovation Norway, The Research Council of Norway, Ministry of Education and Research and Telemark University College

Lorentz symmetry breaking effects on relativistic EPR correlations

Lorentz symmetry breaking effects on relativistic EPR (Einstein-Podolsky-Rosen) correlations are discussed. From the modified Maxwell theory coupled to gravity, we establish a possible scenario of the Lorentz symmetry violation and write an effective metric for the Minkowski spacetime. Then, we obtain the Wigner rotation angle via the Fermi-Walker transport of spinors and consider the WKB ((Wentzel-Kramers-Brillouin) approximation in order to study the influence of Lorentz symmetry breaking effects on the relativistic EPR correlations.Comment: Accepted for publication in The European Physical Journal C. arXiv admin note: substantial text overlap with arXiv:1504.07432, arXiv:1504.07262, arXiv:1412.5080, arXiv:1506.0056