3,824 research outputs found
Stochastic Quantization of Topological Field Theory: Generalized Langevin Equation with Memory Kernel
We use the method of stochastic quantization in a topological field theory
defined in an Euclidean space, assuming a Langevin equation with a memory
kernel. We show that our procedure for the Abelian Chern-Simons theory
converges regardless of the nature of the Chern-Simons coefficient
The pasta phase within density dependent hadronic models
In the present paper we investigate the onset of the pasta phase with
different parametrisations of the density dependent hadronic model and compare
the results with one of the usual parametrisation of the non-linear Walecka
model. The influence of the scalar-isovector virtual delta meson is shown. At
zero temperature two different methods are used, one based on coexistent phases
and the other on the Thomas-Fermi approximation. At finite temperature only the
coexistence phases method is used. npe matter with fixed proton fractions and
in beta-equilibrium are studied. We compare our results with restrictions
imposed on the the values of the density and pressure at the inner edge of the
crust, obtained from observations of the Vela pulsar and recent isospin
diffusion data from heavy-ion reactions, and with predictions from spinodal
calculations.Comment: 15 pages, 11 figures and 7 table
Influência da forma de aplicação de nitrogênio no desempenho produtivo de arroz por aspersão.
Temperamento e desempenho de bovinos de corte de diferentes genótipos criados no sul do Brasil.
Security analysis of standard authentication and key agreement protocols utilising timestamps
We propose a generic modelling technique that can be used to extend existing frameworks for theoretical security analysis in order to capture the use of timestamps. We apply this technique to two of the most popular models adopted in literature (Bellare-Rogaway and Canetti-Krawczyk). We analyse previous results obtained using these models in light of the proposed extensions, and demonstrate their application to a new class of protocols. In the timed CK model we concentrate on modular design and analysis of protocols, and propose a more efficient timed authenticator relying on timestamps. The structure of this new authenticator implies that an authentication mechanism standardised in ISO-9798 is secure. Finally, we use our timed extension to the BR model to establish the security of an efficient ISO protocol for key transport and unilateral entity authentication
Dual equivalence in models with higher-order derivatives
We introduce a class of higher-order derivative models in (2,1) space-time
dimensions. The models are described by a vector field, and contain a
Proca-like mass term which prevents gauge invariance. We use the gauge
embedding procedure to generate another class of higher-order derivative
models, gauge-invariant and dual to the former class. We show that the results
are valid in arbitrary (d,1) space-time dimensions when one discards the
Chern-Simons and Chern-Simons-like terms. We also investigate duality at the
quantum level, and we show that it is preserved in the quantum scenario. Other
results include investigations concerning the gauge embedding approach when the
vector field couples with fermionic matter, and when one adds nonlinearity.Comment: RevTex4, 14 pages; new version includes duality at the quantum level,
and new references. To be published in J. Phys.
Isolamento e caracterização de genes potencialmente envolvidos na resistência a fusariose através de hibridização subtrativa de supressão.
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