Geometrical Expression of Excess Entropy Production

We derive a geometrical expression of the excess entropy production for quasi-static transitions between nonequilibrium steady states of Markovian jump processes, which can be exactly applied to nonlinear and nonequilibrium situations. The obtained expression is geometrical; the excess entropy production depends only on a trajectory in the parameter space, analogous to the Berry phase in quantum mechanics. Our results imply that vector potentials are needed to construct thermodynamics of nonequilibrium steady states

Geometrical Excess Entropy Production in Nonequilibrium Quantum Systems

For open systems described by the quantum Markovian master equation, we study a possible extension of the Clausius equality to quasistatic operations between nonequilibrium steady states (NESSs). We investigate the excess heat divided by temperature (i.e., excess entropy production) which is transferred into the system during the operations. We derive a geometrical expression for the excess entropy production, which is analogous to the Berry phase in unitary evolution. Our result implies that in general one cannot define a scalar potential whose difference coincides with the excess entropy production in a thermodynamic process, and that a vector potential plays a crucial role in the thermodynamics for NESSs. In the weakly nonequilibrium regime, we show that the geometrical expression reduces to the extended Clausius equality derived by Saito and Tasaki (J. Stat. Phys. {\bf 145}, 1275 (2011)). As an example, we investigate a spinless electron system in quantum dots. We find that one can define a scalar potential when the parameters of only one of the reservoirs are modified in a non-interacting system, but this is no longer the case for an interacting system.Comment: 28 pages, 3 figures. 'Remark on the fluctuation theorem' has been revised in ver. 2. Brief Summary has been added in Sec. 1 in ver.

Minimal Model of Stochastic Athermal Systems: Origin of Non-Gaussian Noise

For a wide class of stochastic athermal systems, we derive Langevin-like equations driven by non-Gaussian noise, starting from master equations and developing a new asymptotic expansion. We found an explicit condition whereby the non-Gaussian properties of the athermal noise become dominant for tracer particles associated with both thermal and athermal environments. Furthermore, we derive an inverse formula to infer microscopic properties of the athermal bath from the statistics of the tracer particle. We apply our formulation to a granular motor under viscous friction, and analytically obtain the angular velocity distribution function. Our theory demonstrates that the non-Gaussian Langevin equation is the minimal model of athermal systems.Comment: 10 pages, 5 figure

Dust-to-neutral gas ratio of the intermediate velocity HI clouds derived based on the sub-mm dust emission for the whole sky

We derived, as a proxy for the metallicity, the dust-to-HI ratio of the multiple components, the intermediate-velocity clouds (IVCs), the high-velocity clouds (HVCs), and the local HI, by carrying out a multiple-regression analysis of the 21cm HI emission combined with the sub-mm dust optical depth. The method covers over 80 per cent of the sky contiguously at a resolution of 47arcmin and is distinguished from the absorption line measurements toward bright stars covering a tiny fraction of the sky. Major results include that the ratio of the IVCs is in a range of 0.1-1.5 with a mode at 0.6 (relative to the majority of the local ISM, likewise below) and that a significant fraction, ~20 per cent, of the IVCs include dust-poor gas with a ratio of <0.5. It is confirmed that 80 per cent of the HVC Complex C has a ratio of <0.3, and that the Magellanic Stream has a uniform low ratio <0.1. The results prove that some IVCs have low metallicity gas, contrary to the previous absorption line measurements. Considering that the recent works show that the IVCs are interacting and exchanging momentum with the high metallicity Galactic halo gas, we argue that the high metallicity gas contaminates a significant fraction of the IVCs, and the observed fraction of the low metallicity IVCs gives a secure lower limit. Accordingly, we argue the IVCs include a significant fraction of the low metallicity gas supplied from outside the Galaxy as an alternative to the Galactic-fountain model.Comment: 29 pages, 23 figures, submitted to MNRA

Le patriotisme local de Charles-Édouard Jeanneret dans La Construction des villes et Erneuerungsbewegung en Allemagne

Penser l'architecture par la ressourceIn 1910, Jeanneret began writing a text entitled La Construction des villes, when regionalism was en vogue on a central European scale. The text, however, was never published. We will first examine the content and ideological background of the local patriotism depicted in the text. Then, we will analyze the relationship between Jeanneret’s work and that of Paul Schultze-Naumburg, which is considered to be the source of his patriotism.Jeanneret a écrit l’ouvrage La Construction des villes, dont la rédaction a débuté en 1910, lorsque le régionalisme était en vogue à l’échelle de l’Europe centrale, mais il n’a jamais été publié. Nous allons d’abord examiner le contenu et le contexte idéologique du patriotisme local dans le texte. Ensuite, nous examinerons la relation entre l’œuvre de Jeanneret et Paul Schultze-Naumburg, qui est considérée comme la source de son patriotisme

Geometrical Pumping in Quantum Transport: Quantum Master Equation Approach

For an open quantum system, we investigate the pumped current induced by a slow modulation of control parameters on the basis of the quantum master equation and full counting statistics. We find that the average and the cumulant generating function of the pumped quantity are characterized by the geometrical Berry-phase-like quantities in the parameter space, which is associated with the generator of the master equation. From our formulation, we can discuss the geometrical pumping under the control of the chemical potentials and temperatures of reservoirs. We demonstrate the formulation by spinless electrons in coupled quantum dots. We show that the geometrical pumping is prohibited for the case of non-interacting electrons if we modulate only temperatures and chemical potentials of reservoirs, while the geometrical pumping occurs in the presence of an interaction between electrons

Stochastic Acceleration of Cosmic Rays in the Central Molecular Zone of the Galaxy

Particle acceleration in the inner ~ 200 pc of the Galaxy is discussed, where diffuse TeV gamma-rays have been detected by the High Energy Stereoscopic System (HESS) observation. The diffuse gamma-ray emission has a strong correlation with molecular clouds with large velocity dispersion, indicating the presence of turbulence. It is argued that the turbulence may contribute to the acceleration of cosmic rays via stochastic acceleration. The stochastic acceleration may energize cosmic-ray protons up to ~ 100 TeV and electrons to ~ 1 TeV in a relatively tenuous medium. The difference in the efficiency between protons and electrons supports the hadronic scenario of the diffuse TeV gamma-ray emission.Comment: 4 pages, 1 figure, accepted by PASJ Letter