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Fine structure of Surface Relief Gratings experiment and a generic stochastic Monte Carlo model of the photoinduced mass transport in azopolymer ; We study experimentally and theoretically a doublepeak fine structure of Surface Relief Gratings in azofunctionalized polyetherimide. For the theoretical analysis we develop a stochastic Monte Carlo model for photoinduced mass transport in azobenzene functionalized polymer matrix. The long soughtafter transport of polymer chains from bright to dark places of the illumination pattern is demonstrated and characterized, various scenarios for the intertwined processes of buildup of density and SRG gratings are examined. Model predicts that for some azofunctionalized materials doublepeak SRG maxima can develop in the permanent, quasipermanent or transient regimes.
A bosonic multistate twowell model ; Inspired by the increasing possibility of experimental control in ultracold atomic physics, we introduce a new Lax operator and use it to construct and solve models with two wells and two onwell states together with its generalization for n onwell states. The models are solved by the algebraic Bethe ansatz method and can be viewed as describing two BoseEinstein condensates allowing for an exchange interaction through Josephson tunnelling.
Thermomechanics of hydrogen storage in metallic hydrides modeling and analysis ; A thermodynamically consistent mathematical model for hydrogen adsorption in metal hydrides is proposed. Beside hydrogen diffusion, the model accounts for phase transformation accompanied by hysteresis, swelling, temperature and heat transfer, strain, and stress. We prove existence of solutions of the ensuing system of partial differential equations by a carefullydesigned, semiimplicit approximation scheme. A generalization for a driftdiffusion of multicomponent ionized gas is outlined, too.
A polynomial fR inflation model ; Motivated by the ultraviolet complete theory of quantum gravity, for example the string theory, we investigate a polynomial fR inflation model in detail. We calculate the spectral index and tensortoscalar ratio in the fR inflation model with the form of fR RR2over 6M2lambdanover 2nRnover 3M2n1. Compared to Planck 2013, we find that Rn term should be exponentially suppressed, i.e. lambdanlesssim 102n2.6.
Ultrametric dynamics for the closed fractalcluster resource models ; The evolutional scenario of the resource distribution in the fractalcluster systems which is identified as an organism has been suggested. We propose a model in which the resource redistribution dynamics in the closed system is determined by the ultrametric structure of the system's space. Moreover, each cluster has its own character time of a transfer to the equilibrium state which is determined by the ultrametric size of the cluster. The general equation which determines this dynamics has been written. For the determined type of the resource transitions among clusters, the solution to this equation has been numerically received. The problem of the parameter's identification modeling for the real systems has been discussed.
Variational inference for count response semiparametric regression ; Fast variational approximate algorithms are developed for Bayesian semiparametric regression when the response variable is a count, i.e. a nonnegative integer. We treat both the Poisson and Negative Binomial families as models for the response variable. Our approach utilizes recently developed methodology known as nonconjugate variational message passing. For concreteness, we focus on generalized additive mixed models, although our variational approximation approach extends to a wide class of semiparametric regression models such as those containing interactions and elaborate random effect structure.
Myopic Models of Population Dynamics on Infinite Networks ; Reactiondiffusion equations are treated on infinite networks using semigroup methods. To blend high fidelity local analysis with coarse remote modeling, initial data and solutions come from a uniformly closed algebra generated by functions which are flat at infinity. The algebra is associated with a compactification of the network which facilitates the description of spatial asymptotics. Diffusive effects disappear at infinity, greatly simplifying the remote dynamics. Accelerated diffusion models with conventional eigenfunctions expansions are constructed to provide opportunities for finite dimensional approximation.
Thermodynamics of O3 Classical Heisenberg Model in Multipath Metropolis Simulation ; We study the thermodynamics of classical Heisenberg model using the multipath approach to Metropolis algorithm Monte Carlo simulation. This simulation approach produces uncorrelated results with known precision. Also, it can be easily generalized to other classical models of magnetism. Comparing results obtained from multipath and from singlepath simulations we demonstrate that these approaches produce equivalent results.
Contributions to the model theory of partial differential fields ; In this thesis three topics on the model theory of partial differential fields are considered the generalized Galois theory for partial differential fields, geometric axioms for the theory of partial differentially closed fields, and the existence and properties of the model companion of the theory of partial differential fields with an automorphism. The approach taken here to these subjects is to relativize the algebro geometric notions of prolongation and Dvariety to differential notions with respect to a fixed differential structure.
AdS braneworld with Backreaction ; We review the tachyon model derived from the dynamics of a 3brane moving in the AdS5 bulk. The bulk geometry is based on the RandallSundrum II model extended to include the radion. The effective tachyon Lagrangian is modified due to the backreaction of the brane on the bulk geometry.
Beyond LogSupermodularity Lower Bounds and the Bethe Partition Function ; A recent result has demonstrated that the Bethe partition function always lower bounds the true partition function of binary, logsupermodular graphical models. We demonstrate that these results can be extended to other interesting classes of graphical models that are not necessarily binary or logsupermodular the ferromagnetic Potts model with a uniform external field and its generalizations and special classes of weighted graph homomorphism problems.
Cluster meanfield approach with density matrix renormalization group Application to the hardcore bosonic Hubbard model on a triangular lattice ; We introduce a new numerical method for the solution of selfconsistent equations in the cluster meanfield theory. The method uses the density matrix renormalization group method to solve the associated cluster problem. We obtain an accurate critical value of the supersolidsuperfluid transitions in the hardcore bosonic Hubbard model on a triangular lattice, which is comparable with the recent quantum Monte Carlo results. This algorithm is applicable to more general classes of models with a larger number of degrees of freedom.
State space collapse for critical multistage epidemics ; We study a multistage epidemic model which generalizes the SIR model and where infected individuals go through K0 stages of the epidemic before being removed. An infected individual in stage k1,...,K may infect a susceptible individual, who directly goes to stage k of the epidemic; or it may go to the next stage k1 of the epidemic. For this model, we identify the critical regime in which we establish diffusion approximations. Surprisingly, the limiting diffusion exhibits an unusual form of state space collapse which we analyze in detail.
Three Dimensional Models of RR Lyrae Pulsation ; Preliminary polytropic models of a pulsating star have been constructed using the 3D Hydrocode SPHC. An embedded RayleighTaylor unstable layer is used to study the interaction of pulsation and turbulence. The possible importance of RichtmyerMeshkov instability is noted for large amplitude pulsation. In addition, this model spontaneously generates a strong, hot, shock driven outflow at the upper boundary.
Monte Carlo fixedlag smoothing in statespace models ; This paper presents an algorithm for Monte Carlo fixedlag smoothing in statespace models defined by a diffusion process observed through noisy discretetime measurements. Based on a particles approximation of the filtering and smoothing distributions, the method relies on a simulation technique of conditioned diffusions. The proposed sequential smoother can be applied to general non linear and multidimensional models, like the ones used in environmental applications. The smoothing of a turbulent flow in a highdimensional context is given as a practical example.
Sequential Monte Carlo Bandits ; In this paper we propose a flexible and efficient framework for handling multiarmed bandits, combining sequential Monte Carlo algorithms with hierarchical Bayesian modeling techniques. The framework naturally encompasses restless bandits, contextual bandits, and other bandit variants under a single inferential model. Despite the model's generality, we propose efficient Monte Carlo algorithms to make inference scalable, based on recent developments in sequential Monte Carlo methods. Through two simulation studies, the framework is shown to outperform other empirical methods, while also naturally scaling to more complex problems for which existing approaches can not cope. Additionally, we successfully apply our framework to online videobased advertising recommendation, and show its increased efficacy as compared to current state of the art bandit algorithms.
Notes on the compatibility of type Ia supernovae data and varyingG cosmology ; Observational data for type Ia supernovae, shows that the expansion of the universe is accelerated. This accelerated expansion can be described by a cosmological constant or by dark energy models like quintessence. An interesting question may be raised here. Is it possible to describe the accelerated expansion of universe using varyingG cosmological models Here we shall show that the price for having accelerated expansion in slowvaryingG models in which the dynamical terms of G are ignored is to have highly nonconserved matter and also that it is in contradiction with other data.
DBI inflation with a nonminimally coupled GaussBonnet term ; We study the inflation in a model with a GaussBonnet term which is nonminimally coupled to a DBI field. We study the spectrum of the primordial perturbations in detail. The nonGaussianity of this model is considered and the amplitude of the nonGaussianity is studied in both the equilateral and orthogonal configurations. By taking various functions of the DBI field, inflaton potential and the GaussBonnet coupling term, we test the model with observational data and find some constraints on the GaussBonnet coupling parameter.
Efficient and realistic device modeling from atomic detail to the nanoscale ; As semiconductor devices scale to new dimensions, the materials and designs become more dependent on atomic details. NEMO5 is a nanoelectronics modeling package designed for comprehending the critical multiscale, multiphysics phenomena through efficient computational approaches and quantitatively modeling new generations of nanoelectronic devices as well as predicting novel device architectures and phenomena. This article seeks to provide updates on the current status of the tool and new functionality, including advances in quantum transport simulations and with materials such as metals, topological insulators, and piezoelectrics.
Activity date estimation in timestamped interaction networks ; We propose in this paper a new generative model for graphs that uses a latent space approach to explain timestamped interactions. The model is designed to provide global estimates of activity dates in historical networks where only the interaction dates between agents are known with reasonable precision. Experimental results show that the model provides better results than local averages in dense enough networks
New Class of Ndimensional Braneworlds ; The new class of the nonstationary solutions to the system of Ndimensional equations for coupled gravitational and massless scalar field is found. The model represents a single N1brane in a spacetime with one large infinite and N5 small compact spacelike extra dimensions. In some particular cases the model corresponds to the gravitational and scalar field standing waves bounded by the brane. These braneworlds can be relevant in string and other higher dimensional models.
Jammed lattice sphere packings ; We generate and study an ensemble of isostatic jammed hardsphere lattices. These lattices are obtained by compression of a periodic system with an adaptive unit cell containing a single sphere until the point of mechanical stability. We present detailed numerical data about the densities, pair correlations, force distributions, and structure factors of such lattices. We show that this model retains many of the crucial structural features of the classical hardsphere model and propose it as a model for the jamming and glass transitions that enables exploration of much higher dimensions than are usually accessible.
Transport Equation for NambuGoto Strings ; We consider a covariant approach to coarsegraining a network of interacting NambuGoto strings. A transport equation is constructed for a spatially flat Friedmann universe. In Minkowski space and with no spatial dependence this model agrees with a previous model. Thus it likewise converges to an equilibrium with a factorizability property. We present an argument that this property does not depend on a string chaos' assumption on the correlations between strings. And in contrast to the earlier model, this transport equation agrees with conservation equations for a fluid of strings derived from a different perspective.
Quantum Gaudin model and classical KP hierarchy ; This short note is a review of the intriguing connection between the quantum Gaudin model and the classical KP hierarchy recently established in 1. We construct the generating function of integrals of motion for the quantum Gaudin model with twisted boundary conditions the master Toperator and show that it satisfies the bilinear identity and Hirota equations for the classical KP hierarchy. This implies that zeros of eigenvalues of the master Toperator in the spectral parameter have the same dynamics as the CalogeroMoser system of particles.
Exact transition probabilities in the threestate LandauZenerCoulomb model ; We obtain the exact expression for the matrix of nonadiabatic transition probabilities in the model of three interacting states with a timedependent Hamiltonian. Unlike other known solvable LandauZenerlike problems, our solution is generally expressed in terms of hypergeometric functions that have relatively complex behavior, e.g. the obtained transition probabilities may show multiple oscillations as functions of parameters of the model Hamiltonian.
Transition densities for strongly degenerate time inhomogeneous random models ; In this paper we study the existence of densities for strongly degenerate stochastic differential equations whose coefficients depend on time and are not globally Lipschitz. In these models neither local ellipticity nor the strong Hormander condition is satisfied. In this general setting we show that continuous transition densities indeed exist in all neighborhoods of points where the weak Hormander condition is satisfied. We also exhibit regions where these densities remain positive. We then apply these results to stochastic HodgkinHuxley models as a first step towards the study of ergodicity properties of such systems.
Rescaled Magnetization for Critical Bipartite MeanFields Models ; We consider a bipartite generalization of the CurieWeiss model in a critical regime. In order to study the asymptotic behavior of the random vector of the total magnetization we apply the change of variables that diagonalizes the Hessian matrix of the pressure functional associated to the model. We obtain a new vector that, suitably rescaled, weakly converges to the product of a Gaussian distribution and a distribution proportional to expxi x4, where the positive constant xi can be computed from the pressure functional.
Paraactive learning ; Training examples are not all equally informative. Active learning strategies leverage this observation in order to massively reduce the number of examples that need to be labeled. We leverage the same observation to build a generic strategy for parallelizing learning algorithms. This strategy is effective because the search for informative examples is highly parallelizable and because we show that its performance does not deteriorate when the sifting process relies on a slightly outdated model. Parallel active learning is particularly attractive to train nonlinear models with nonlinear representations because there are few practical parallel learning algorithms for such models. We report preliminary experiments using both kernel SVMs and SGDtrained neural networks.
Valence double parton distributions of the nucleon in a simple model ; Valence double parton distribution functions of the nucleon are evaluated in the framework of a simple model, where the conservation of the longitudinal momentum is taken into account. The leadingorder DGLAP QCD evolution from the low quarkmodel scale to higher renormalization scales is carried out via the Mellin moments of the distributions. Results of the valence quark correlation function show that in general the double distributions cannot be approximated as a product of the singleparticle distributions.
Probing a cosmological model with a 0 3H2 decayingvacuum ; In this work we study the evolution of matterdensity perturbations for an arbitrary Lambdat model, and specialize our analysis to the particular phenomenological law Lambda Lambda0 3beta H2. We study the evolution of the cosmic star formation rate in this particular dark energy scenario and, by constraining the beta parameter using both the age of the universe and the cosmic star formation rate curve, we show that it leads to a reasonable physical model for betalesssim 0.1.
Lowscale seesaw models versus Nrm eff ; We consider the contribution of the extra sterile states in generic lowscale seesaw models to extra radiation, parametrized by Nrm eff. We find that the value of Nrm eff is roughly independent of the seesaw scale within a wide range. We explore the full parameter space in the case of two extra sterile states and find that these models are strongly constrained by cosmological data for any value of the seesaw scale below mathcal O100MeV.
Higher Order Theories and its Relationship with Noncommutativity ; We present a relationship between noncommutativity and higher order time derivative theories using a method perturbative. We introduce a generalization of the ChernSimons Quantum Mechanics for higher order time derivatives. This model presents noncommutativity in a natural way when we project to states of low energy. Compared with the usual model, our system presents noncommutativity without the necessity of taking the limit of strong field. We quantized the theory using a Bopp's shift of the noncommutative variables and we obtain an spectrum without negatives energies. In addition we extend the model to high order derivatives and noncommutativity with variable dependent parameter.
Front Velocity and Directed Polymers in Random Medium ; We consider a stochastic model of N evolving particles studied by Brunet and Derrida. This model can be seen as a directed polymer in random medium with N sites in the transverse direction. Cook and Derrida, use heuristic arguments to obtain a formula for the ground state energy of the polymer. In this paper, we formalize their argument and show that there is an additional term in the formula in the critical case. We also consider a generalization of the model, and show that in the noncritical case the behavior is basically the same, whereas in the critical case a new correction appears.
Selfdual soliton solutions in a ChernSimonsCP1 model with a nonstandard kinetic term ; A generalization of the ChernSimonsCP1 model is considered by introducing a nonstandard kinetic term. For a particular case, of this nonstandard kinetic term, we show that the model support selfdual Bogomolnyi equations. The BPS energy has a bound proportional to the sum of the magnetic flux and the CP1 topological charge. The selfdual equations are solved analytically and verified numerically.
Numerical study of the DysonSchwinger equations for the WessZumino model ; Supersymmetric models, in most cases, suffer from the lack of nonperturbative techniques. Recently, an approach based on DysonSchwinger equations has been proposed for the massless WessZumino model. In this case, the equations for the selfenergies of the fields were solved with the strong ansatz to take them all equal. We show, by numerically solving the equations, that this is a too strong choice as also solutions with all different selfenergies are acceptable and more generic. This could have interesting implications for supersymmetry breaking.
Asymmetric exclusion processes on a closed network with bottlenecks ; We study the generic nonequilibrium steady states in asymmetric exclusion processes on a closed network with bottlenecks. To this end we proposes and study closed simple networks with multiplyconnected nonidentical junctions. Depending upon the parameters that define the network junctions and the particle number density, the models display phase transitions with both static and moving density inhomogeneities. The currents in the models can be tuned by the junction parameters. Our models highlight how extended and point defects may affect the density profiles in a closed directed network. Phenomenological implications of our results are discussed.
Estimating complex causal effects from incomplete observational data ; Despite the major advances taken in causal modeling, causality is still an unfamiliar topic for many statisticians. In this paper, it is demonstrated from the beginning to the end how causal effects can be estimated from observational data assuming that the causal structure is known. To make the problem more challenging, the causal effects are highly nonlinear and the data are missing at random. The tools used in the estimation include causal models with design, causal calculus, multiple imputation and generalized additive models. The main message is that a trained statistician can estimate causal effects by judiciously combining existing tools.
Thermodynamics of the unified dark fluid with fast transition ; In the socalled unified dark fluid models, the dark sector gets simplified because dark matter and dark energy are replaced by a single fluid that behaves as the former at early times and as the latter at late times. In this short paper we analyze this class of models from the thermodynamic viewpoint. While the second law of thermodynamics is satisfied, the first two derivatives of the entropies of the apparent horizon and of the energy components suffer such a sharp oscillation that doubts are raised about the soundness of this class of models.
Global regularity for a logarithmically supercritical hyperdissipative dyadic equation ; We prove global existence of smooth solutions for a slightly supercritical dyadic model. We consider a generalized version of the dyadic model introduced by KatzPavlovic 2005 and add a viscosity term with critical exponent and a supercritical correction. This model catches for the dyadic a conjecture that for NavierStokes equations was formulated by Tao 2009.
Microscopic Calibration and Validation of CarFollowing Models A Systematic Approach ; Calibration and validation techniques are crucial in assessing the descriptive and predictive power of carfollowing models and their suitability for analyzing traffic flow. Using real and generated floatingcar and trajectory data, we systematically investigate following aspects Data requirements and preparation, conceptional approach including local maximumlikelihood and global LSE calibration with several objective functions, influence of the data sampling rate and measuring errors, the effect of data smoothing on the calibration result, and model performance in terms of fitting quality, robustness, parameter orthogonality, completeness and plausible parameter values.
mathcalC, mathcalP, mathcalT operations and classical point charged particle dynamics ; The action of parity inversion, time inversion and charge conjugation operations on several differential equations for a classical point charged particle are described. Moreover, we consider the notion of it symmetrized acceleration Deltaq that for models of point charged electrodynamics is sensitive to deviations from the standard Lorentz force equation. It is shown that Deltaq can be observed with current or near future technology and that it is an useful quantity for probing radiation reaction models. To illustrate these points we consider four different models for the dynamics of point charged particles and radiation reaction.
The Tilt of Primordial Gravitational Waves Spectra from BICEP2 ; In this paper we constrain the tilt of the spectra of primordial gravitational waves from Background Imaging of Cosmic Extragalactic Polarization BICEP2 data only. We find r0.210.100.04 and nt0.060.230.25 at 68 C.L. which implies that a scaleinvariant primordial gravitational waves spectra is consistent with BICEP2 nicely. Our results provide strong evidence for supporting inflation model, and the alternative models, for example the ekpyrotic model which predicts nt2, are ruled out at more than 5sigma significance.
A Laplace's method for series and the semiclassical analysis of epidemiological models ; We develop a Laplace's method to compute the asymptotic expansions of sums of sharply peaked sequences. These series arise as discretizations Riemann sums of sharplypeaked integrals, whose asymptotic behavior can be computed by the standard Laplace's method. We apply the Laplace's method for series to the WKB i.e. semiclassical analysis of stochastic models of population biology, with special focus on the SIS model. In particular we show that two different and widelyused approaches to the semiclassical limit, i.e. either considering a semiclassical probability distribution or a semiclassical generating function, are equivalent.
Lowdimensional behavior of Kuramoto model with inertia in complex networks ; Lowdimensional behavior of large systems of globally coupled oscillators has been intensively investigated since the introduction of the OttAntonsen ansatz. In this report, we generalize the OttAntonsen ansatz to secondorder Kuramoto models in complex networks. With an additional inertia term, we find a lowdimensional behavior similar to the firstorder Kuramoto model, derive a selfconsistent equation and seek the timedependent derivation of the order parameter. Numerical simulations are also conducted to verify our analytical results.
Dark energy models through nonextensive Tsallis' statistics ; The accelerated expansion of the Universe is one of the greatest challenges of modern physics. One candidate to explain this phenomenon is a new field called dark energy. In this work we have used the Tsallis nonextensive statistical formulation of the Friedmann equation to explore the BarbozaAlcaniz and ChevalierPolarskiLinder parametric dark energy models and the WangMeng and Dalal vacuum decay models. After that, we have discussed the observational tests and the constraints concerning the Tsallis nonextensive parameter.
CP violation in Bto D using multipion tau decays ; Present experimental datas have shown a 3.8sigma level discrepancy with the standard model in overlineBto Dtaubarnutau. Some new physics models have been considered to explain this discrepancy possibly with new source of the CP violation. In this paper, we construct CP violating observables by using multipion decays in Bto Dtaunutau, and estimate sensitivity of these observables to generic CP violating operators. We also discuss possibilities of CP violation in leptoquark models and in 2HDM of typeIII.
Quark Wigner Distributions and Orbital Angular Momentum in Lightfront Dressed Quark Model ; We calculate the Wigner functions for a quark target dressed with a gluon. These give a combined position and momentum space information of the quark distributions and are related to both generalized parton distributions GPDs and transverse momentum dependent parton distributions TMDs. We calculate and compare the different definitions of quark orbital angular momentum in this model. We compare our results with other model calculations.
Semiparametric inference for the absorption features of a growthfragmentation model ; In the present paper, we focus on semiparametric methods for estimating the absorption probability and the distribution of the absorbing time of a growthfragmentation model observed within a long time interval. We establish that the absorption probability is the unique solution in an appropriate space of a Fredholm equation of the second kind whose parameters are unknown. We estimate this important characteristic of the underlying process by solving numerically the estimated Fredholm equation. Even if the study has been conducted for a particular model, our method is quite general.
Imaginaries and definable types in algebraically closed valued fields ; The text is based on notes from a class entitled em Model Theory of Berkovich Spaces, given at the Hebrew University in the fall term of 2009, and retains the flavor of class notes. It includes an exposition of material from citehhmcrelle, citehhm and citeHL, regarding definable types in the model completion of the theory of valued fields, and the classification of imaginary sorts. The latter is given a new proof, based on definable types rather than invariant types, and on the notion of em generic reparametrization. I also try to bring out the relation to the geometry of citeHL stably dominated definable types as the model theoretic incarnation of a Berkovich point.
Simplified Models for Vector Boson Scattering at ILC and CLIC ; Quasielastic scattering of the vector bosons W and Z is a sensitive probe of the details of electroweak symmetry breaking, and a key process at future lepton colliders. We discuss the limitations of a modelindependent effectivetheory approach and describe the extension to a class of Simplified Models that is applicable to all energies in a quantitative way, and enables realistic MonteCarlo simulations. The framework has been implemented in the MonteCarlo event generator WHIZARD.
Gauge Field Turbulence as a Cause of Inflation in ChernSimons Modified Gravity ; In this paper, we study the dynamics of the ChernSimons Inflation Model proposed by Alexander, Marciano and Spergel. According to this model, inflation begins when a fermion current interacts with a turbulent gauge field in a space larger than some critical size. This mechanism appears to work by driving energy from the initial random spectrum into a narrow band of frequencies, similar to the inverse energy cascade seen in MHD turbulence. In this work we focus on the dynamics of the interaction using phase diagrams and a thorough analysis of the evolution equations. We show that in this model inflation is caused by an overdamped harmonic oscillator driving waves in the gauge field at their resonance frequency.
Zeno Dynamics for Open Quantum Systems ; In this paper we formulate limit Zeno dynamics of general open systems as the adiabatic elimination of fast components. We are able to exploit previous work on adiabatic elimination of quantum stochastic models to give explicitly the conditions under which open Zeno dynamics will exist. The open systems formulation is further developed as a framework for Zeno master equations, and Zeno filtering that is, quantum trajectories based on a limit Zeno dynamical model. We discuss several models from the point of view of quantum control. For the case of linear quantum stochastic systems we present a condition for stability of the asymptotic Zeno dynamics.
A Process Model of Quantum Mechanics ; A process model of quantum mechanics utilizes a combinatorial game to generate a discrete and finite causal space upon which can be defined a selfconsistent quantum mechanics. An emergent spacetime M and continuous wave function arise through a nonuniform interpolation process. Standard nonrelativistic quantum mechanics emerges under the limit of infinite information the causal space grows to infinity and infinitesimal scale the separation between points goes to zero. The model has the potential to address several paradoxes in quantum mechanics while remaining computationally powerful.
Bs,d0 to ellell Decays in the Aligned TwoHiggsDoublet Model ; The rare decays Bs,d0 to ellell are analyzed within the general framework of the aligned twoHiggs doublet model. We present a complete oneloop calculation of the relevant shortdistance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data.
Do we really need to write documentation for a system CASE tool addons generatoreditor for a precise documentation ; One of the common problems of system development projects is that the system documentation is often outdated and does not describe the latest version of the system. The situation is even more complicated if we are speaking not about a natural language description of the system, but about its formal specification. In this paper we discuss how the problem could be solved by updating the documentation automatically, by generating a new formal specification from the model if the model is frequently changed.
Twisted Skyrmion String ; We study nonlinear sigma model, especially Skyrme model without twist and Skyrme model with twist twisted Skyrmion string. Twist term, mkz, is indicated in vortex solution. Necessary condition for stability of vortex solution has consequence that energy of vortex is minimum and scalefree vortex solution is neutrally stable to changes in scale. We find numerically that the value of vortex minimum energy per unit length for twisted Skyrmion string is 20.37times 1060texteVm.
Neutrino Mixing With NonZero 13 In ZeeBabu Model ; The exact solution for the neutrino mass matrix of the ZeeBabu model is derived. Tribimaximal mixing imposes conditions on the Yukawa couplings, from which the normal mass hierarchy is preferred. The derived conditions give a possibility of Majorana maximal mathrmCP violation in the neutrino sector. We have shown that nonzero theta13 is generated if Yukawa couplings between leptons almost equal to each other. The model gives some regions of the parameters where neutrino mixing angles and the normal neutrino mass hierarchy obtained consistent with the recent experimental data.
Adiabatic Monte Carlo ; A common strategy for inference in complex models is the relaxation of a simple model into the more complex target model, for example the prior into the posterior in Bayesian inference. Existing approaches that attempt to generate such transformations, however, are sensitive to the pathologies of complex distributions and can be difficult to implement in practice. Leveraging the geometry of thermodynamic processes I introduce a principled and robust approach to deforming measures that presents a powerful new tool for inference.
Hole propagation in the orbital compass models ; We explore the propagation of a single hole in the generalized quantum compass model which interpolates between fully isotropic antiferromagnetic AF phase in the Ising model and nematic order of decoupled AF chains for frustrated compass interactions. We observe coherent hole motion due to either interorbital hopping or due to the threesite effective hopping, while quantum spin fluctuations in the ordered background do not play any role.
Cosmological meaning of the gravitational gauge group ; It is shown that among the Rbeta SabcSabc models, only the one with beta12 has nonvanishing torsion effect in the RobertsonWalker universe filled with a spin fluid, where Sabc denotes torsion. Moreover, the torsion effect in that model is found to be able to replace the bigbang singularity by a big bounce. Furthermore, we find that the model can be obtained under a KaluzaKleinlike ansatz, by assuming that the gravitational gauge group is the de Sitter group.
Factorization of anticanonical maps of Fano type varieties ; The purpose of the present paper is to generalize Sakai's work on anticanonical models of rational surfaces to varieties of Fano type. We first prove a characterization of Fano type varieties using the singularities of anticanonical models. Secondly, we study the decomposition of the anticanonical map using the KXminimal model program.
Multilayered graphbased multidocument summarization model ; Multidocument summarization is a process of automatic generation of a compressed version of the given collection of documents. Recently, the graphbased models and ranking algorithms have been actively investigated by the extractive document summarization community. While most work to date focuses on homogeneous connecteness of sentences and heterogeneous connecteness of documents and sentences e.g. sentence similarity weighted by document importance, in this paper we present a novel 3layered graph model that emphasizes not only sentence and document level relations but also the influence of under sentence level relations e.g. a part of sentence similarity.
Estimating Vector Fields on Manifolds and the Embedding of Directed Graphs ; This paper considers the problem of embedding directed graphs in Euclidean space while retaining directional information. We model a directed graph as a finite set of observations from a diffusion on a manifold endowed with a vector field. This is the first generative model of its kind for directed graphs. We introduce a graph embedding algorithm that estimates all three features of this model the lowdimensional embedding of the manifold, the data density and the vector field. In the process, we also obtain new theoretical results on the limits of Laplacian type matrices derived from directed graphs. The application of our method to both artificially constructed and real data highlights its strengths.
The constitution of visual perceptual units in the functional architecture of V1 ; Scope of this paper is to consider a mean field neural model which takes into account the functional neurogeometry of the visual cortex modelled as a group of rotations and translations. The model generalizes well known results of Bressloff and Cowan which, in absence of input, accounts for hallucination patterns. The main result of our study consists in showing that in presence of a visual input, the eigenmodes of the linearized operator which become stable represent perceptual units present in the image. The result is strictly related to dimensionality reduction and clustering problems.
Statistical Intercell Interference Modeling for CapacityCoverage Tradeoff Analysis in Downlink Cellular Networks ; Interference shapes the interplay between capacity and coverage in cellular networks. However, interference is nondeterministic and depends on various system and channel parameters including user scheduling, frequency reuse, and fading variations. We present an analytical approach for modeling the distribution of intercell interference in the downlink of cellular networks as a function of generic fading channel models and various scheduling schemes. We demonstrate the usefulness of the derived expressions in calculating locationbased and averagebased data rates in addition to capturing practical tradeoffs between cell capacity and coverage in downlink cellular networks.
Modeling Algorithms in SystemC and ACL2 ; We describe the formal language MASC, based on a subset of SystemC and intended for modeling algorithms to be implemented in hardware. By means of a specialpurpose parser, an algorithm coded in SystemC is converted to a MASC model for the purpose of documentation, which in turn is translated to ACL2 for formal verification. The parser also generates a SystemC variant that is suitable as input to a highlevel synthesis tool. As an illustration of this methodology, we describe a proof of correctness of a simple 32bit radix4 multiplier.
Coupled fluids model in FRW spacetime ; In this paper, we analyze a two coupled fluids model by investigating several solutions for accelerated universe in flat FRW spacetime. One of the fluids can be identified with the matter and the model possesses the standard matter solution also. Beyond the removal of the coincidence problem, we will see how the coupling may change the description of the energy contents of the universe and which features can be aquired with respect to the standard decoupled cases.
Quotients of Strongly Proper Forcings and Guessing Models ; We prove that a wide class of strongly proper forcing posets have quotients with strong properties. Specifically, we prove that quotients of forcing posets which have simple universal strongly generic conditions on a stationary set of models by certain nice regular suborders satisfy the omega1approximation property. We prove that the existence of stationarily many omega1guessing models in Pomega2Htheta, for sufficiently large cardinals theta, is consistent with the continuum being arbitrarily large, solving a problem of Viale and Weiss.
Forcing with Adequate Sets of Models as Side Conditions ; We present a general framework for forcing on omega2 with finite conditions using countable models as side conditions. This framework is based on a method of comparing countable models as being membership related up to a large initial segment. We give several examples of this type of forcing, including adding a function on omega2, adding a nonreflecting stationary subset of omega2 cap textrmcofomega, and adding an omega1Kurepa tree.
Wellposedness for the FENE dumbbell model of polymetric flows in Besov spaces ; In this paper we mainly investigate the Cauchy problem of the finite extensible nonlinear elastic FENE dumbbell model with dimension dgeq2. We first proved the local wellposedness for the FENE model in Besov spaces by using the LittlewoodPaley theory. Then by an accurate estimate we get a blowup criterion. Moreover, if the initial data is perturbation around equilibrium, we obtain a global existence result. Our obtained results generalize recent results in 8.
Survival Models for the Duration of BidAsk Spread Deviations ; Many commonly used liquidity measures are based on snapshots of the state of the limit order book LOB and can thus only provide information about instantaneous liquidity, and not regarding the local liquidity regime. However, trading in the LOB is characterised by many intraday liquidity shocks, where the LOB generally recovers after a short period of time. In this paper, we capture this dynamic aspect of liquidity using a survival regression framework, where the variable of interest is the duration of the deviations of the spread from a prespecified level. We explore a large number of model structures using a branchandbound subset selection algorithm and illustrate the explanatory performance of our model.
Anomalous finite size corrections in random field models ; The presence of a random magnetic field in ferromagnetic systems leads, in the broken phase, to an anomalous Osqrt1N convergence of some thermodynamic quantities to their asymptotic limits. Here we show a general method, based on the replica trick, to compute analytically the Osqrt1N finite size correction to the average free energy. We apply this method to two mean field Ising models, fully connected and random regular graphs, and compare the results to exact numerical algorithms. We argue that this behaviour is present in finite dimensional models as well.
A twostage model for dealing with temporal degradation of credit scoring ; This work is attached to the BRICS 2013 competition. We propose a twostage model for dealing with the temporal degradation of credit scoring models. This methodology produced motivating results in a 1year horizon. We anticipate that it can be extended to other applications of risk assessment with great success. Future extensions should cover predictions in larger time frames and consider lagged periods. This methodology can be further improved if more information about the economic cycles is integrated in the forecasting of default.
The role of radiative corrections on an extradimensional SUSY model ; Theories with extradimensional coordinates provide interesting mechanisms to achieve the rupture of symmetries. Here we present a novel alternative to the usual geometric considerations to achieve supersymmetric breaking for an extradimensional WessZumino model. A supersymmetric model is constructed where the superpotential contains an effective supersymmetric non renormalizable operator, which generates, after compactification, the explicitly rupture of supersymmetry for the excited KaluzaKlein excitations. The supersymmetry breaking is, in turn, communicated, by the radiatives corrections, to the zero mode.
Projecting Ising Model Parameters for Fast Mixing ; Inference in general Ising models is difficult, due to high treewidth making treebased algorithms intractable. Moreover, when interactions are strong, Gibbs sampling may take exponential time to converge to the stationary distribution. We present an algorithm to project Ising model parameters onto a parameter set that is guaranteed to be fast mixing, under several divergences. We find that Gibbs sampling using the projected parameters is more accurate than with the original parameters when interaction strengths are strong and when limited time is available for sampling.
Universality classes for models of inflation ; We show that the cosmological evolution of a scalar field in a potential can be obtained from a renormalisation group equation. The slow roll regime of inflation models is understood in this context as the slow evolution close to a fixed point, described by the methods of renormalisation group. This explains in part the universality observed in the predictions of a certain number of inflation models. We illustrate this behavior on a certain number of examples and discuss it in the context of the AdSCFT correspondence.
Sparse Quadratic Discriminant Analysis and Community Bayes ; We develop a class of rules spanning the range between quadratic discriminant analysis and naive Bayes, through a path of sparse graphical models. A group lasso penalty is used to introduce shrinkage and encourage a similar pattern of sparsity across precision matrices. It gives sparse estimates of interactions and produces interpretable models. Inspired by the connectedcomponents structure of the estimated precision matrices, we propose the community Bayes model, which partitions features into several conditional independent communities and splits the classification problem into separate smaller ones. The community Bayes idea is quite general and can be applied to nonGaussian data and likelihoodbased classifiers.
Autonomous models on a Cayley tree ; The most general single species autonomous reactiondiffusion model on a Cayley tree with nearestneighbor interactions is introduced. The stationary solutions of such models, as well as their dynamics, are discussed. To study dynamics of the system, directionallysymmetric Green function for evolution equation of average number density is obtained. In some limiting cases the Green function is studied. Some examples are worked out in more detail.
Inversion identities for inhomogeneous face models ; We derive exact inversion identities satisfied by the transfer matrix of inhomogeneous interactionroundaface IRF models with arbitrary boundary conditions using the underlying integrable structure and crossing properties of the local Boltzmann weights. For the critical restricted solidonsolid RSOS models these identities together with some information on the analytical properties of the transfer matrix determine the spectrum completely and allow to derive the Bethe equations for both periodic and general open boundary conditions.
OKMC simulations of FeC systems under irradiation sensitivity studies ; This paper continues our previous work on a nanostructural evolution model for FeC alloys under irradiation, using Object Kinetic Monte Carlo modeling techniques. We here present a number of sensitivity studies of parameters of the model, such as the carbon content in the material, represented by generic traps for point defects, the importance of traps, the size dependence of traps and the effect of the dose rate.
On backgroundindependent renormalization of spin foam models ; In this article we discuss an implementation of renormalization group ideas to spin foam models, where there is no a priori length scale with which to define the flow. In the context of the continuum limit of these models, we show how the notion of cylindrical consistency of path integral measures gives a natural analogue of Wilson's RG flow equations for backgroundindependent systems. We discuss the conditions for the continuum measures to be diffeomorphisminvariant, and consider both exact and approximate examples.
Late time Acceleration and Role of Skewness in Anisotropic models ; We study cosmological models with anisotropy in expansion rates in the context of the recent observations predicting an accelerating universe. In the absence of any anisotropy in the cosmic fluid, it is shown that the role of skewness in directional Hubble rates is crucial in deciding the behavior of the model. We find that incorporation of skewness leads to a more evolving effective equation of state parameter.
Cosmic Acceleration and Anisotropic models with Magnetic field ; Plane symmetric cosmological models are investigated with or without any dark energy components in the field equations. Keeping an eye on the recent observational constraints concerning the accelerating phase of expansion of the universe, the role of magnetic field is assessed. In the absence of dark energy components, magnetic field can favour an accelerating model even if we take a linear relationship between the directional Hubble parameters. In presence of dark energy components in the form of a time varying cosmological constant, the influence of magnetic field is found to be limited.
A Dark Energy Model in KaluzaKlein Cosmology ; We study a dynamic Lambda model with varying gravitational constant G under the KaluzaKlein cosmology. Physical features and the limitations of the present model have been explored and discussed. Solutions are found mostly in accordance with the observed features of the accelerating universe. Interestingly, signature flipping of the deceleration parameter is noticed and the present age of the Universe is also attainable under certain stringent conditions. We find that the time variation of gravitational constant is not permitted without vintage Lambda.
Light mass galileon and late time acceleration of the Universe ; We study Galileon scalar field model by considering the lowest order Galileon term in the lagrangian, partialmu phi2 Boxphi by invoking a field potential. We use Statefinder hierarchy to distinguish the light mass galileon models with different potentials amongst themselves and from the LambdaCDM behaviour. The Om diagnostic is applied to cosmological dynamics and observational constraints on the model parameters are studied using SNHubbleBAO data.
Qualitative modeling of the dynamics of detonations with losses ; We consider a simplified model for the dynamics of onedimensional detonations with generic losses. It consists of a single partial differential equation that reproduces, at a qualitative level, the essential properties of unsteady detonation waves, including pulsating and chaotic solutions. In particular, we investigate the effects of shock curvature and friction losses on detonation dynamics. To calculate steadystate solutions, a novel approach to solving the detonation eigenvalue problem is introduced that avoids the wellknown numerical difficulties associated with the presence of a sonic point. By using unsteady numerical simulations of the simplified model, we also explore the nonlinear stability of steadystate or quasisteady solutions.
Probabilistic model of N correlated binary random variables and nonextensive statistical mechanics ; The framework of nonextensive statistical mechanics, proposed by Tsallis, has been used to describe a variety of systems. The nonextensive statistical mechanics is usually introduced in a formal way, thus simple models exhibiting some important properties described by the nonextensive statistical mechanics are useful to provide deeper physical insights. In this article we present a simple model, consisting of a onedimensional chain of particles characterized by binary random variables, that exhibits both the extensivity of the generalized entropy with q1 and a qGaussian distribution in the limit of the large number of particles.
Efficient inference of protein structural ensembles ; It is becoming clear that traditional, singlestructure models of proteins are insufficient for understanding their biological function. Here, we outline one method for inferring, from experiments, not only the most common structure a protein adopts native state, but the entire ensemble of conformations the system can adopt. Such ensemble mod els are necessary to understand intrinsically disordered proteins, enzyme catalysis, and signaling. We suggest that the most difficult aspect of generating such a model will be finding a small set of configurations to accurately model structural heterogeneity and present one way to overcome this challenge.
Effective models of membranes from symmetry breaking ; We show how to obtain all the models of the continuous description of membranes by constructing the appropriate nonlinear realizations of the Euclidean symmetries of the embedding. The procedure has the advantage of giving a unified formalism with which the models are generated and highlights the relevant order parameters in each phase. We use our findings to investigate a fluid description of both tethered and hexatic membranes, showing that both the melting and the loss of local order induce long range interactions in the high temperature fluid phase. The results can be used to understand the appearance of intrinsic ripples in crystalline membranes in a thermal bath.
Bianchi typeI, typeIII and KantowskiSachs solutions in fT gravity ; In the context of modified teleparallel theory of gravity, we undertake cosmological anisotropic models and search for their solutions. Within a suitable choice of nondiagonal tetrads, the decoupled equations of motion are obtained for BianchiI, BianchiIII and KantowskiSachs models, from which we obtain the correspondent solutions. By the way, energy density and pressures are also obtained, showing, as an important result, that our universe may live a quintessence like universe even still anisotropic models are considered.
A maximumentropy description of animal movement ; We introduce a class of maximumentropy states that naturally includes within it all of the major continuoustime stochastic processes that have been applied to animal movement, including Brownian motion, OrnsteinUhlenbeck motion, integrated OrnsteinUhlenbeck motion, a recently discovered hybrid of the previous models, and a new model that describes centralplace foraging. We are also able to predict a further hierarchy of new models that will emerge as data quality improves to better resolve the underlying continuity of animal movement. Finally, we also show that Langevin equations must obey a fluctuationdissipation theorem to generate processes that fall from this class of maximumentropy distributions.
Statistical system with fantom scalar interaction. II. Macroscopic Equations and Cosmological Models ; Based on the proposed earlier by the Author approach to macroscopic description of scalar interaction, this paper develops the macroscopic model of relativistic plasma with a fantom scalar interaction of elementary particles. In the article the macroscopic equations for a statistical system with scalar interaction of particles are obtained and the complete set of macroscopic equations describing cosmological models is built.
Kfield kinks stability, exact solutions and new features ; We study a class of noncanonical real scalar field models in 11dimensional flat spacetime. We first derive the general criterion for the classical linear stability of an arbitrary static soliton solution of these models. Then we construct firstorder formalisms for some typical models and derive the corresponding kink solutions. The linear structures of these solutions are also qualitatively analyzed and compared with the canonical kink solutions.
Constrained Dirac gluino mediation ; We perform a comparison study of the Constrained Minimal Supersymmetric Standard Model and Constrained General Gauge Mediation with and without a heavy Dirac gluino. These extremely simple models have very few free parameters and exhibit the characteristic features of supersoftness and supersafeness. We determine the characteristic low energy spectra, the production cross sections of key processes at the Large Hadron Collider and the degree of fine tuning for a representative range of parameters for each model.
VaidyaTikekar Type Superdense Star Admitting Conformal Motion in Presence of Quintessence Field ; To explain the reason of accelerated expansion of our universe dark energy is a suitable candidate. Motivated by this concept in the present paper we have obtained a new model of an anisotropic superdense star which admits conformal motions in presence of quintessence field which is characterized by a parameter omega with omega lies in the range 1 to 13.The model has been developed by choosing VaidyaTitekar ansatz P C Vaidya and R Tikekar 1982J. Astrophys .Astron. 3 325.Our model satisfy all the physical requirements.We have analyze our result analytically as well as with the help of graphical representation.
Aftershock production rate of driven viscoelastic interfaces ; We study analytically and by numerical simulations the statistics of the aftershocks generated after large avalanches in models of interface depinning that include viscoelastic relaxation effects. We find in all the analyzed cases that the decay law of aftershocks with time can be understood by considering the typical roughness of the interface and its evolution due to relaxation. In models where there is a single viscoelastic relaxation time there is an exponential decay of the number of aftershocks with time. In models in which viscoelastic relaxation is wavevector dependent we typically find a power law dependence of the decay rate, compatible with the Omori law. The factors that determine the value of the decay exponent are analyzed.
A Bayesian Beta Markov Random Field Calibration of the Term Structure of Implied Risk Neutral Densities ; We build on the work in Fackler and King 1990, and propose a more general calibration model for implied risk neutral densities. Our model allows for the joint calibration of a set of densities at different maturities and dates through a Bayesian dynamic Beta Markov Random Field. Our approach allows for possible time dependence between densities with the same maturity, and for dependence across maturities at the same point in time. This approach to the problem encompasses model flexibility, parameter parsimony and, more importantly, information pooling across densities.
Uncertainties in models of stellar structure and evolution ; Numerous physical aspects of stellar physics have been presented in Ses sion 2 and the underlying uncertainties have been tentatively assessed. We try here to highlight some specific points raised after the talks and during the general discus sion at the end of the session and eventually at the end of the workshop. A table of model uncertainties is then drawn with the help of the participants in order to give the state of the art in stellar modeling uncertainties as of July 2013.
Implementation of Levy CARMA model in Yuima package ; The paper shows how to use the R package yuima available on CRAN for the simulation and the estimation of a general L'evy Continuous Autoregressive Moving Average CARMA model. The flexibility of the package is due to the fact that the user is allowed to choose several parametric L'evy distribution for the increments. Some numerical examples are given in order to explain the main classes and the corresponding methods implemented in yuima package for the CARMA model.
Fractional Mirror Symmetry ; Mirror symmetry relates type IIB string theory on a CalabiYau 3fold to type IIA on the mirror CY manifold, whose complex structure and Kaehler moduli spaces are exchanged. We show that the mirror map is a particular case of a more general quantum equivalence, fractional mirror symmetry, between CalabiYau compactifications and nonCY ones. As was done by Greene and Plesser for mirror symmetry, we obtain these new dualities by considering orbifolds of Gepner models, of asymmetric nature, leading to superconformal field theories isomorphic to the original ones, but with a different targetspace interpretation. The associated LandauGinzburg models involve both chiral and twisted chiral multiplets hence cannot be lifted to ordinary gauged linear sigmamodels.