190 research outputs found

    Steady state fluctuations of the dissipated heat for a quantum stochastic model

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    We introduce a quantum stochastic dynamics for heat conduction. A multi-level subsystem is coupled to reservoirs at different temperatures. Energy quanta are detected in the reservoirs allowing the study of steady state fluctuations of the entropy dissipation. Our main result states a symmetry in its large deviation rate function.Comment: 41 pages, minor changes, published versio

    Quantum Hypothesis Testing and Non-Equilibrium Statistical Mechanics

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    We extend the mathematical theory of quantum hypothesis testing to the general WW^*-algebraic setting and explore its relation with recent developments in non-equilibrium quantum statistical mechanics. In particular, we relate the large deviation principle for the full counting statistics of entropy flow to quantum hypothesis testing of the arrow of time.Comment: 60 page

    Equilibration, generalized equipartition, and diffusion in dynamical Lorentz gases

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    We prove approach to thermal equilibrium for the fully Hamiltonian dynamics of a dynamical Lorentz gas, by which we mean an ensemble of particles moving through a dd-dimensional array of fixed soft scatterers that each possess an internal harmonic or anharmonic degree of freedom to which moving particles locally couple. We establish that the momentum distribution of the moving particles approaches a Maxwell-Boltzmann distribution at a certain temperature TT, provided that they are initially fast and the scatterers are in a sufficiently energetic but otherwise arbitrary stationary state of their free dynamics--they need not be in a state of thermal equilibrium. The temperature TT to which the particles equilibrate obeys a generalized equipartition relation, in which the associated thermal energy kBTk_{\mathrm B}T is equal to an appropriately defined average of the scatterers' kinetic energy. In the equilibrated state, particle motion is diffusive

    A note on the Landauer principle in quantum statistical mechanics

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    The Landauer principle asserts that the energy cost of erasure of one bit of information by the action of a thermal reservoir in equilibrium at temperature T is never less than kTlog2kTlog 2. We discuss Landauer's principle for quantum statistical models describing a finite level quantum system S coupled to an infinitely extended thermal reservoir R. Using Araki's perturbation theory of KMS states and the Avron-Elgart adiabatic theorem we prove, under a natural ergodicity assumption on the joint system S+R, that Landauer's bound saturates for adiabatically switched interactions. The recent work of Reeb and Wolf on the subject is discussed and compared

    The Diffusion of the Magnetization Profile in the XX-model

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    By the CC^*-algebraic method, we investigate the magnetization profile in the intermediate time of diffusion. We observe a transition from monotone profile to non-monotone profile. This transition is purely thermal.Comment: Accepted for publication in Phys. Rev.

    Influence of CAN fertilizer and seed inoculation with NS Nitragin on glycine max plant on pseudogley soil type

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    Soybean [Glycine max (L.) Merr.] is the most important legume because it is an essential source of dietary protein and oil for animal feed and food production. Good soil with wellplanned program of fertilization is the main factor of soybean production. Soybean yield will be reduced when essential nutrients are deficient. Sufficient soil fertility combined with a well-planned fertilization program is a main component for high soybean production. The aim of this investigation was to estimate the effects of fertilization and seed inoculation on height of soybean plant in humid year. Two factors were tested: 1. CAN fertilization and 2. seed inoculation. Four treatments of CAN fertilization were tested: Control - 0 kg N ha-1; 50 kg N ha-1; 100 kg N ha-1 and 150 kg N ha-1. Two factors of seed inoculation (SI) were tested: Without SI and with SI. Results showed that fertilizers and seed inoculation significantly increased the values of soybean productivity. Cost effective is the application of 50 kg N ha-1 and it is recommended on the basis of this study

    One-dimensional Dirac operators with zero-range interactions: Spectral, scattering, and topological results

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    17 pagesInternational audienceThe spectral and scattering theory for 1-dimensional Dirac operators with mass mm and with zero-range interactions are fully investigated. Explicit expressions for the wave operators and for the scattering operator are provided. These new formulae take place in a representation which links, in a suitable way, the energies -\infty and ++\infty, and which emphasizes the role of ±m\pm m. Finally, a topological version of Levinson's theorem is deduced, with the threshold effects at ±m\pm m automatically taken into account

    Adiabatic non-equilibrium steady states in the partition free approach

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    Consider a small sample coupled to a finite number of leads, and assume that the total (continuous) system is at thermal equilibrium in the remote past. We construct a non-equilibrium steady state (NESS) by adiabatically turning on an electrical bias between the leads. The main mathematical challenge is to show that certain adiabatic wave operators exist, and to identify their strong limit when the adiabatic parameter tends to zero. Our NESS is different from, though closely related with the NESS provided by the Jak{\v s}i{\'c}-Pillet-Ruelle approach. Thus we partly settle a question asked by Caroli {\it et al} in 1971 regarding the (non)equivalence between the partitioned and partition-free approaches
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