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The dynamics of one species chemical kinetics is studied. Chemical reactions are modelled by means of continuous time Markov processes whose probability distribution obeys a suitable master equation. A large deviation theory is formally…

Statistical Mechanics · Physics 2015-03-14 Carlos Escudero , Andres M. Rivera , Pedro J. Torres

Starting from a representation of the early time evolution of a dynamical system in terms of the polynomial expression of some observable f (t) as a function of the time variable in some interval 0 < t < T, we investigate how to…

Statistical Mechanics · Physics 2009-11-07 Simon Gluzman , Didier Sornette

Kaniadakis entropy is a one-parameter deformation of the classical Boltzmann-Gibbs-Shannon entropy, arising from a self-consistent relativistic statistical theory. Assuming a Kaniadakis-type generalization of the entropy associated with the…

General Relativity and Quantum Cosmology · Physics 2023-11-09 Gaetano Lambiase , Giuseppe Gaetano Luciano , Ahmad Sheykhi

Recent theoretical studies have gradually deepened our understanding of the one-dimensional (1D) Kardar-Parisi-Zhang (KPZ) universality class even in the large deviation regime, but numerical methods for studying KPZ large deviations remain…

Statistical Mechanics · Physics 2026-02-09 Yuta Yanagibashi , Kazumasa A. Takeuchi

We study local features, and provide a topological insight into the global structure of the probability density distribution and of the pattern of the optimal paths for large rare fluctuations away from a stable state. In contrast to…

Condensed Matter · Physics 2009-10-22 Mark I. Dykman , Mark M. Millonas , Vadim N. Smelyanskiy

The high precision attained by cosmological data in the last few years has increased the interest in exact solutions. Analytic expressions for solutions in the Standard Model are presented here for all combinations of $\Lambda = 0$,…

General Relativity and Quantum Cosmology · Physics 2009-09-29 R. Aldrovandi , R. R. Cuzinatto , L. G. Medeiros

The recently developed method (Paper 1) enabling one to investigate the evolution of dynamical systems with an accuracy not dependent on time is developed further. The classes of dynamical systems which can be studied by that method are…

Instrumentation and Methods for Astrophysics · Physics 2018-11-05 V. G. Gurzadyan , A. A. Kocharyan

The basic strategy underlying models of spontaneous wave function collapse (collapse models) is to modify the Schroedinger equation by including nonlinear stochastic terms, which tend to localize wave functions in space in a dynamical…

Quantum Physics · Physics 2015-06-18 A. Bassi , H. Ulbricht

We consider a generalized Einstein-Cartan theory, in which we add the unique covariant dimension four operators to general relativity that couples fermionic spin current to the torsion tensor (with an arbitrary strength). Since torsion is…

General Relativity and Quantum Cosmology · Physics 2017-11-01 Stefano Lucat , Tomislav Prokopec

Multiple $\Lambda$CDM cosmology is studied in a way that is formally a classical analog of the Casimir effect. Such cosmology corresponds to a time-dependent dark fluid model or, alternatively, to its scalar field presentation, and it…

General Relativity and Quantum Cosmology · Physics 2015-06-05 E. Elizalde , A. N. Makarenko , S. Nojiri , V. V. Obukhov , S. D. Odintsov

The study of complex systems is limited by the fact that only few variables are accessible for modeling and sampling, which are not necessarily the most relevant ones to explain the systems behavior. In addition, empirical data typically…

Data Analysis, Statistics and Probability · Physics 2013-11-04 Matteo Marsili , Iacopo Mastromatteo , Yasser Roudi

We consider a model for Darwinian evolution in an asexual population with a large but non-constant populations size characterized by a natural birth rate, a logistic death rate modelling competition and a probability of mutation at each…

Probability · Mathematics 2015-08-28 Martina Baar , Anton Bovier , Nicolas Champagnat

We introduce a new class of quantum models with time-dependent Hamiltonians of a special scaling form. By using a couple of time-dependent unitary transformations, the time evolution of these models is expressed in terms of related systems…

Quantum Physics · Physics 2009-11-07 L. Samaj

A quantum theory for the Markovian dynamics of an open system under the unsharp observation which is continuous in time, is developed within the CCR stochastic approach. A stochastic classical equation for the posterior evolution of quantum…

Mathematical Physics · Physics 2009-11-11 V. P. Belavkin

We derive the matching conditions for cosmological perturbations in a Friedmann Universe where the equation of state undergoes a sharp jump, for instance as a result of a phase transition. The physics of the transition which is needed to…

General Relativity and Quantum Cosmology · Physics 2009-07-09 Nathalie Deruelle , V. F. Mukhanov

We study the dynamics near finite-time singularities of flat isotropic universes filled with two interacting but otherwise arbitrary perfect fluids. The overall dynamical picture reveals a variety of asymptotic solutions valid locally…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Spiros Cotsakis , Georgia Kittou

Complex systems are characterized by a huge number of degrees of freedom often interacting in a non-linear manner. In many cases macroscopic states, however, can be characterized by a small number of order parameters that obey stochastic…

Data Analysis, Statistics and Probability · Physics 2012-02-20 David Kleinhans

We present a rich class of exact solutions which contains radiation-dominated and matter-dominated models for the early and late universe. They include a variable cosmological ``constant'' which is derived from a higher dimension and…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Hongya Liu , Paul S. Wesson

After reviewing the cosmological constant problem - why is Lambda not huge? - I outline the two basic approaches that had emerged by the late 1980s, and note that each made a clear prediction. Precision cosmological experiments now indicate…

High Energy Physics - Theory · Physics 2007-05-23 Raphael Bousso

Cosmological models with time dependent $\Lambda$ (read as $\Lambda (t)$) have been investigated widely in the literature. Models that solve background dynamics analytically, are of special interest. Additionally, the allowance of past or…

General Relativity and Quantum Cosmology · Physics 2018-01-08 Supriya Pan