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Constraining the Lattice Fluid Dark Energy from SNe Ia, BAO and OHD ; Sanchez and Lacombe have ever developed a lattice fluid theory based on a welldefined statistical mechanical model. Taking the lattice fluid as a candidate of dark energy, we investigate the cosmic evolution of this fluid. Using the combined observational data of Type Ia Supernova SNe Ia, Baryon Acoustic Oscillations BAO and Observational Hubble Data OHD, we find the best fit value of the parameter in the model, A 0.30.10.1. Then the cosmological implications of the model are presented. |
Bianchi typeI string cosmological model in the presence of a magnetic field classical versus loop quantum cosmology approaches ; A Bianchi typeI cosmological model in the presence of a magnetic flux along a cosmological string is considered. The first objective of this study is to investigate Einstein equations using a tractable assumption usually accepted in the literature. Quantum effects of the present cosmological model are examined in the framework of loop quantum cosmology. Finally we draw a parallel between the classical and quantum approaches. |
SpectralFunction Sum Rules in Supersymmetry Breaking Models ; The technique of Weinberg's spectralfunction sum rule is a powerful tool for a study of models in which global symmetry is dynamically broken. It enables us to convert information on the shortdistance behavior of a theory to relations among physical quantities which appear in the lowenergy picture of the theory. We apply such technique to general supersymmetry breaking models to derive new sum rules. |
Semiparametric efficiency bounds for seemingly unrelated conditional moment restrictions ; This paper addresses the problem of semiparametric efficiency bounds for conditional moment restriction models with different conditioning variables. We characterize such an efficiency bound, that in general is not explicit, as a limit of explicit efficiency bounds for a decreasing sequence of unconditional marginal moment restriction models. An iterative procedure for approximating the efficient score when this is not explicit is provided. Our theoretical results complete and extend existing results in the literature, provide new insight for the theory of semiparametric efficiency bounds literature and open the door to new applications. In particular, we investigate a class of regressionlike mean regression, quantile regression,... models with missing data. |
Uniform rotation ; We describe the spacetime model of a uniformly rotating frame of reference satisfying the Helmholtz free mobility postulate, as we implemented it in a preceding article citeBel1, and we discuss the implications of this model as it concerns the problematic of the one way or two ways velocity of light derived from the model and its relationship with the universal constant c. |
A Note on the Equivalence between the Normal and the Lognormal Implied Volatility A Model Free Approach ; First, we show that implied normal volatility is intimately linked with the incomplete Gamma function. Then, we deduce an expansion on implied normal volatility in terms of the timevalue of a European call option. Then, we formulate an equivalence between the implied normal volatility and the lognormal implied volatility with any strike and any model. This generalizes a known result for the SABR model. Finally, we adress the issue of the breakeven move of a deltahedged portfolio. |
Convergent Expectation Propagation in Linear Models with Spikeandslab Priors ; Exact inference in the linear regression model with spike and slab priors is often intractable. Expectation propagation EP can be used for approximate inference. However, the regular sequential form of EP REP may fail to converge in this model when the size of the training set is very small. As an alternative, we propose a provably convergent EP algorithm PCEP. PCEP is proved to minimize an energy function which, under some constraints, is bounded from below and whose stationary points coincide with the solution of REP. Experiments with synthetic data indicate that when REP does not converge, the approximation generated by PCEP is often better. By contrast, when REP converges, both methods perform similarly. |
Soliton surfaces associated with CPN1 sigma models ; Soliton surfaces associated with CPN1 sigma models are constructed using the Generalized Weierstrass and the FokasGel'fand formulas for immersion of 2D surfaces in Lie algebras. The considered surfaces are defined using continuous deformations of the zerocurvature representation of the model and its associated linear spectral problem. The theoretical framework is discussed in detail and several new examples of such surfaces are presented. |
Model Independent Search in 2Dimensional Mass Space ; A model independent method to search for particles of unknown masses in events with missing energy is presented. The only assumption is the topology of the decay chain. The method is tested in events with top pairs decaying leptonically with the presence of two neutrinos in the final state. Possible applications are searches for a heavy resonance decaying to top pairs as well as next generation heavy quarks. Similar topologies are predicted by supersymmetric models with Rparity conservation resulting in final states with two invisible neutralinos. |
Qualitative study of perfectfluid FriedmannLemaitreRobertsonWalker models with a cosmological constant ; The evolution of spatially homogeneous and isotropic cosmological models containing a perfect fluid with equation of state pwrho and a cosmological constant Lambda is investigated for arbitrary combinations of w and Lambda, using standard qualitative analysis borrowed from classical mechanics. This approach allows one to consider a large variety of situations, appreciating similarities and differences between models, without solving the Friedmann equation, and is suitable for an elementary course in cosmology. |
Gravitational oscillations in multidimensional anisotropic model with cosmological constant and their contributions into the energy of vacuum ; Were studied classical oscillations of background metric in the multidimensional anisotropic model of Kazner in the deSitter stage. Obtained dependence of fluctuations on dimension of spacetime with infinite expansion. Stability of the model could be achieved when number of spacelike dimensions equals or more then four. Were calculated contributions to the density of vacuum energy, that are providing by proper oscillations of background metric and compared with contribution of cosmological arising of particles due to expansion. As it turned out, contribution of gravitational oscillation of metric into density of vacuum energy should play significant role in the deSitter stage. |
Low and Upper Bound of Approximate Sequence for the Entropy Rate of Binary Hidden Markov Processes ; In the paper, the approximate sequence for entropy of some binary hidden Markov models has been found to have two bound sequences, the low bound sequence and the upper bound sequence. The error bias of the approximate sequence is bound by a geometric sequence with a scale factor less than 1 which decreases quickly to zero. It helps to understand the convergence of entropy rate of generic hidden Markov models, and it provides a theoretical base for estimating the entropy rate of some hidden Markov models at any accuracy. |
Stochastic Electron Acceleration in SNR RX J1713.73946 ; Stochastic acceleration of charged particles due to their interactions with plasma waves may be responsible for producing superthermal particles in a variety of astrophysical systems. This process can be described as a diffusion process in the energy space with the FokkerPlanck equation. In this paper, a timedependent numerical code is used to solve the reduced FokkerPlanck equation involving only time and energy variables with general forms of the diffusion coefficients. We also propose a selfsimilar model for particle acceleration in Sedov explosions and use the TeV SNR RX J1713.73946 as an example to demonstrate the model characteristics. Markov Chain Monte Carlo method is utilized to constrain model parameters with observations. |
Black hole solutions in FR gravity with conformal anomaly ; In this paper, we consider FRRfR theory instead of Einstein gravity with conformal anomaly and look for its analytical solutions. Depending on the free parameters, one may obtain both uncharged and charged solutions for some classes of FR models. Calculation of Kretschmann scalar shows that there is a singularity located at r0, which the geometry of uncharged charged solution is corresponding to the Schwarzschild ReissnerNordstrom singularity. Further, we discuss the viability of our models in details. We show that these models can be stable depending on their parameters and in different epoches of the universe. |
3D Tensor Field Theory Renormalization and Oneloop functions ; We prove that the rank 3 analogue of the tensor model defined in arXiv1111.4997 hepth is renormalizable at all orders of perturbation. The proof is given in the momentum space. The oneloop gamma and betafunctions of the model are also determined. We find that the model with a unique coupling constant for all interactions and a unique wave function renormalization is asymptotically free in the UV. |
Electroweak Symmetry Breaking Beyond the Standard Model ; In this talk, I shall address two key issues related to electroweak symmetry breaking. First, how finetuned different models are that trigger this phenomenon Second, even if a light Higgs boson exists, does it have to be necessarily elementary After a brief introduction, I shall first review the finetuning aspects of the MSSM, NMSSM, generalized NMSSM and GMSB scenarios. I shall then compare and contrast the little Higgs, composite Higgs and the Higgsless models. Finally, I shall summarize by giving a broad overview on where we stand at the end of 2011. |
A Goal Programming Model with Satisfaction Function for Risk Management and Optimal Portfolio Diversification ; We extend the classical risk minimization model with scalar risk measures to the general case of setvalued risk measures. The problem we obtain is a setvalued optimization model and we propose a goal programmingbased approach with satisfaction function to obtain a solution which represents the best compromise between goals and the achievement levels. Numerical examples are provided to illustrate how the method works in practical situations. |
Multicritical tensor models and hard dimers on spherical random lattices ; Random tensor models which display multicritical behaviors in a remarkably simple fashion are presented. They come with entropy exponents gamma m1m, similarly to multicritical random branched polymers. Moreover, they are interpreted as models of hard dimers on a set of random lattices for the sphere in dimension three and higher. Dimers with their exclusion rules are generated by the different interactions between tensors, whose coupling constants are dimer activities. As an illustration, we describe one multicritical point, which is interpreted as a transition between the dilute phase and a crystallized phase, though with negative activities. |
Multinucleon ejection model for Meson Exchange Current neutrino interactions ; A model is proposed to describe pairs or triples of nucleons ejected from nucleus as a result of Meson Exchange Current neutrino interaction. The model can be easily implemented in Monte Carlo neutrino event generators. It can provide a help in identifying true charge current quasielastic events and allow for better determination of the systematic error of neutrino energy reconstruction in neutrino oscillation experiments |
Topological phase transition in a network model with preferential attachment and node removal ; Preferential attachment is a popular model of growing networks. We consider a generalized model with random node removal, and a combination of preferential and random attachment. Using a highdegree expansion of the master equation, we identify a topological phase transition depending on the rate of node removal and the relative strength of preferential vs. random attachment, where the degree distribution goes from a power law to one with an exponential tail. |
Physics Beyond Standard Model in Neutron Beta Decay ; Limits from neutron beta decay on parameters describing physics beyond the Standard Model are presented. New Physics is described by the most general Lorentz invariant effective Hamiltonian involving vector, scalar and tensor operators and Standard Model fields only. Twoparameter fits to the decay parameters measured in free neutron beta decay have been done, in some cases indicating rather big dependence of the results on gAgV ratio of nucleon form factors at zero fourmomentum transfer. |
Open Universe Model Description by Mathieu Functions ; A model of the open Universe described by a conformally flat 4metric is considered. The gravitational equations with a perfect Pascal fluid as a source are reduced to the nonlinear equation of oscillations. It is proposed to consider this equation as the Mathieu equation encompassing some cosmological models. It is shown that the behaviour of the Universe state function is in qualitative accordance with the Big Bang scenario. |
Observational tests of inflation with a field derivative coupling to gravity ; A field kinetic coupling with the Einstein tensor leads to a gravitationally enhanced friction during inflation, by which even steep potentials with theoretically natural model parameters can drive cosmic acceleration. In the presence of this nonminimal derivative coupling we place observational constraints on a number of representative inflationary models such as chaotic inflation, inflation with exponential potentials, natural inflation, and hybrid inflation. We show that most of the models can be made compatible with the current observational data mainly due to the suppressed tensortoscalar ratio. |
Holographic, new agegraphic and ghost dark energy models in fractal cosmology ; We investigate the holographic, new agegraphic and ghost dark energy models in the framework of fractal cosmology. We consider a fractal FRW universe filled with the dark energy and dark matter. We obtain the equation of state parameters of the selected dark energy models in the ultraviolet regime and discuss on their implications. |
Extension of a radiative neutrino mass model based on a cosmological view point ; We consider an extension of the radiative neutrino mass model at TeV regions so as to give the origin for inflation of the universe. This extension also gives a consistent explanation for both the origin of baryon number asymmetry and dark matter. A small scalar coupling which plays a crucial role in the neutrino mass generation in the original model may be related to parameters which are control inflation. |
An Econophysics Model for the Migration Phenomena ; Knowing and modelling the migration phenomena and especially the social and economic consequences have a theoretical and practical importance, being related to their consequences for development, economic progress or as appropriate, regression, environmental influences etc. One of the causes of migration, especially of the interregional and why not intercontinental, is that resources are unevenly distributed, and from the human perspective there are differences in culture, education, mentality, collective aspirations etc. This study proposes a new econophysics model for the migration phenomena. |
On bouncing solutions in nonlocal gravity ; A nonlocal modified gravity model with an analytic function of the d'Alembert operator is considered. This model has been recently proposed as a possible way of resolving the singularities problem in cosmology. We present an exact bouncing solution, which is simpler compared to the already known one in this model in the sense it does not require an additional matter to satisfy all the gravitational equations. |
Comment on Resolution of the AbrahamMinkowski Dilemma ; In a recent Letter by Barnett S. M. Barnett, Phys. Rev. Lett. 104, 070401 2010, a totalmomentum model is proposed for resolution of the AbrahamMinkowski dilemma. In this model, Abraham's and Minkowski's momentums are, respectively, a component of the same total momentum, with the former being the kinetic momentum and the latter the canonical momentum. In this Comment, I would like to indicate that this physical model is not consistent with global momentumenergy conservation law in the principleofrelativity frame. |
Calculation of statistical entropic measures in a model of solids ; In this work, a onedimensional model of crystalline solids based on the Dirac comb limit of the KronigPenney model is considered. From the wave functions of the valence electrons, we calculate a statistical measure of complexity and the FisherShannon information for the lower energy electronic bands appearing in the system. All these magnitudes present an extremal value for the case of solids having halffilled bands, a configuration where in general a high conductivity is attained in real solids, such as it happens with the monovalent metals. |
Bregman divergence as general framework to estimate unnormalized statistical models ; We show that the Bregman divergence provides a rich framework to estimate unnormalized statistical models for continuous or discrete random variables, that is, models which do not integrate or sum to one, respectively. We prove that recent estimation methods such as noisecontrastive estimation, ratio matching, and score matching belong to the proposed framework, and explain their interconnection based on supervised learning. Further, we discuss the role of boosting in unsupervised learning. |
Worm algorithms for the 3state Potts model with magnetic field and chemical potential ; We discuss worm algorithms for the 3state Potts model with external field and chemical potential. The complex phase problem of this system can be overcome by using a flux representation where the new degrees of freedom are dimer and monomer variables. Working with this representation we discuss two different generalizations of the conventional Prokof'evSvistunov algorithm suitable for Monte Carlo simulations of the model at arbitrary chemical potential and evaluate their performance. |
The Coalgebraic Structure of Cell Complexes ; The relative cell complexes with respect to a generating set of cofibrations are an important class of morphisms in any model structure. In the particular case of the standard algebraic model structure on textbfTop, we give a new expression of these morphisms by defining a category of relative cell complexes, which has a forgetful functor to the arrow category. This allows us to prove a conjecture of Richard Garner considering the algebraic weak factorisation system given in that algebraic model structure between cofibrations and trivial fibrations, we show that the category of relative cell complexes is equivalent to the category of coalgebras. |
Discretely holomorphic parafermions and integrable boundary conditions ; In twodimensional statistical models possessing a discretely holomorphic parafermion, we introduce a modified discrete CauchyRiemann equation on the boundary of the domain, and we show that the solution of this equation yields integrable boundary Boltzmann weights. This approach is applied to i the squarelattice On loop model, where the exact locations of the special and ordinary transitions are recovered, and ii the FateevZamolodchikov ZN spin model, where a new rotationinvariant, integrable boundary condition is discovered for generic N. |
Multiphotons and PhotonJets ; We discuss an extension of the Standard Model with a new vectorboson decaying predominantly into a multiphoton final state through intermediate light degrees of freedom. The model has a distinctive phase in which the photons are collimated. As such, they would fail the isolation requirements of standard multiphoton searches, but group naturally into a novel object, the photonjet. Once defined, the photonjet object facilitates more inclusive searches for similar phenomena. We present a concrete model, discuss photonjets more generally, and outline some strategies that may prove useful when searching for such objects. |
Coherent Price Systems and UncertaintyNeutral Valuation ; We consider fundamental questions of arbitrage pricing arising when the uncertainty model is given by a set of possible mutually singular probability measures. With a single probability model, essential equivalence between the absence of arbitrage and the existence of an equivalent martingale measure is a folk theorem, see Harrison and Kreps 1979. We establish a microeconomic foundation of sublinear price systems and present an extension result. In this context we introduce a prior dependent notion of marketed spaces and viable price systems. We associate this extension with a canonically altered concept of equivalent symmetric martingale measure sets, in a dynamic trading framework under absence of prior depending arbitrage. We prove the existence of such sets when volatility uncertainty is modeled by a stochastic differential equation, driven by Peng's GBrownian motions. |
Adaptive Covariance Estimation with model selection ; We provide in this paper a fully adaptive penalized procedure to select a covariance among a collection of models observing i.i.d replications of the process at fixed observation points. For this we generalize previous results of Bigot and al. and propose to use a data driven penalty to obtain an oracle inequality for the estimator. We prove that this method is an extension to the matricial regression model of the work by Baraud. |
Loop Quantization of the Supersymmetric TwoDimensional BF Model ; In this paper we consider the quantization of the 2d BF model coupled to topological matter. Guided by the rigid supersymmetry this system can be viewed as a superBF model, where the field content is expressed in terms of superfields. A canonical analysis is done and the constraints are then implemented at the quantum level in order to construct the Hilbert space of the theory under the perspective of Loop Quantum Gravity methods. |
The women day storm ; On behalf of the International Women Day, the Sun gave a hot kiss to our mother Earth in a form of a full halo CME generated by the yesterday's double Xclass flare. The resulting geomagnetic storm gives a good opportunity to compare the performance of space weather forecast models operating in nearrealtime. We compare the forecasts of most major models and identify some common problems. We also present the results of our own nearrealtime forecast models. |
Noncommutative Mixmaster Cosmologies ; In this paper we investigate a variant of the classical mixmaster universe model of anisotropic cosmology, where the spatial sections are noncommutative 3tori. We consider ways in which the discrete dynamical system describing the mixmaster dynamics can be extended to act on the noncommutative torus moduli, and how the resulting dynamics differs from the classical one, for example, in the appearance of exotic smooth structures. We discuss properties of the spectral action, focussing on how the slowroll inflation potential determined by the spectral action affects the mixmaster dynamics. We relate the model to other recent results on spectral action computation and we identify other physical contexts in which this model may be relevant. |
NambuSigma model and effective membrane actions ; We propose an effective action for a p'brane with open pbranes ending on it. The action has dual descriptions similar to the commutative and noncommutative ones of the DBI action for Dbranes and open strings. The Poisson structure governing the noncommutativity of the Dbrane is replaced by a Nambu structure and the openclosed string relations are generalized to the case of p'branes utilizing a novel Nambu sigma model description of pbranes. In the case of an M5brane our action interpolates between M5actions already proposed in the literature and matrix model like actions involving Nambu structures. |
Dirichlet Process Mixtures of Generalized Mallows Models ; We present a Dirichlet process mixture model over discrete incomplete rankings and study two Gibbs sampling inference techniques for estimating posterior clusterings. The first approach uses a slice sampling subcomponent for estimating cluster parameters. The second approach marginalizes out several cluster parameters by taking advantage of approximations to the conditional posteriors. We empirically demonstrate 1 the effectiveness of this approximation for improving convergence, 2 the benefits of the Dirichlet process model over alternative clustering techniques for ranked data, and 3 the applicability of the approach to exploring large realworld ranking datasets. |
On Supermultiplet Twisting and SpinStatistics ; Twisting of offshell supermultiplets in models with 11dimensional spacetime has been discovered in 1984, and was shown to be a generic feature of offshell representations in worldline supersymmetry two decades later. It is shown herein that in all supersymmetric models with spacetime of four or more dimensions, this offshell supermultiplet twisting, if nontrivial, necessarily maps regular nonghost supermultiplets to ghost supermultiplets. This feature is shown to be ubiquitous in all fully offshell supersymmetric models with BVBRSTtreated constraints. |
Existence and Asymptotic Behavior of Solutions to a Semilinear HyperbolicParabolic Model of Chemotaxis ; We consider a general hyperbolic model of chemotaxis in the multidimensional case. For this system we show the global existence of smooth solutions to the Cauchy problem and we determine their asymptotic behavior. Since this model does not enter in the classical framework of dissipative problems, we analyze it combining the features of the hyperbolic and the parabolic parts and using detailed decay estimates of the Green function. |
Probing flavor changing neutral currents and CP violation through the decay h cb W in the two Higgs doublet model ; We discuss the formulation of the general twoHiggs doublet model type III, which incorporates flavor changing neutral scalar interactions FCNSI and CP violation from several sources. CP violation can arise either from Yukawa terms or from the Higgs potential, and it can explicit or spontaneous. We discuss the case that includes CP violation with Yukawa textures to control FCNSI and evaluate the CP asymmetry for the decay h cb W, which may allow to test the patterns of FCNSI and CP violation, that arises in these models. |
Pushout of quasifinite and flat group schemes over a Dedekind ring ; Let G, G1 and G2 be quasifinite and flat group schemes over a complete discrete valuation ring R, varphi1Gto G1 any morphism of Rgroup schemes and varphi2Gto G2 a model map. We construct the pushout P of G1 and G2 over G in the category of Raffine group schemes. In particular when varphi1 is a model map too we show that P is still a model of the generic fibre of G. We also provide a short proof for the existence of cokernels and quotients of finite and flat group schemes over any Dedekind ring. |
Inverse seesaw and dark matter in models with exotic lepton triplets ; We show that models with exotic leptons transforming as E 1,3,1 under the standard model gauge symmetry are well suited for generating neutrino mass via a radiative inverse seesaw. This approach realizes natural neutrino masses and allows multiple new states to appear at the TeV scale. The exotic leptons are therefore good candidates for new physics that can be probed at the LHC. Furthermore, remnant lowenergy symmetries ensure a stable dark matter candidate, providing a link between dark matter and the origins of neutrino mass. |
Broadcast Search in Innovation Contests Case for Hybrid Models ; Organizations use broadcast search to identify new avenues of innovation. Research on innovation contests provides insights on why excellent ideas are created in a broadcast search. However, there is little research on how excellent ideas are selected. Drawing from the brainstorming literature we find that the selection of excellent ideas needs further investigation. We propose that a hybrid model may lead to selection of better ideas. The hybrid model is a broadcast search approach that exploits the strengths of different actors and procedures in idea generation and the selection phase. |
The AizenmanSimsStarr scheme and Parisi formula for mixed pspin spherical models ; The Parisi formula for the free energy in the spherical models with mixed even pspin interactions was proven in Michel Talagrand 16. In this paper we study the general mixed pspin spherical models including pspin interactions for odd p. We establish the AizenmanSimsStarr scheme and from this together with many wellknown results and Dmitry Panchenko's recent proof on the Parisi ultrametricity conjecture 11, we prove the Parisi formula. |
PecceiQuinn extended gaugemediation model with vectorlike matter ; We construct a gaugemediated SUSY breaking model with vectorlike matters combined with the PecceiQuinn mechanism to solve the strong CP problem. The PecceiQuinn symmetry plays an essential role for generating sizable masses for the vectorlike matters and the muterm without introducing dangerous CP angle. The model naturally explains both the 125GeV Higgs mass and the muon anomalous magnetic moment. The stabilization of the PecceiQuinn scalar and the cosmology of the saxion and axino are also discussed. |
A model for ultrarelativistic spherically symmetric PreHawking radiating gravitational collapse ; In this paper we present a simple but nonsimplistic model of gravitational collapse with thermal emission of preHawking radiation. We apply Einstein equations to a timedependant spherically symmetric metric and an ultrarelativistic stressenergy tensor. In our model, particles either radially approach the center of the star as collapsing matter, or radially flee from it. |
The existence of Bogomolny decompositions for gauged baby Skyrme models ; The Bogomolny decompositions Bogomolny equations for the gauged baby Skyrme models restricted and full one, in 20dimensions, are derived, for some general classes of the potentials. The conditions, which must be satisfied by the potentials, for each of these mentioned models, are also derived. |
Schroedinger models for solutions of the BetheSalpeter equation in Minkowski space ; By application of the 'geometric spectral inversion' technique, which we have recently generalized to accommodate also singular interaction potentials, we construct from spectral data emerging from the solution of the Minkowskispace formulation of the homogeneous BetheSalpeter equation describing bound states of two spinless particles a Schroedinger approach to such states in terms of nonrelativistic potential models. This spectrally equivalent modeling of bound states yields their qualitative features masses, form factors, etc. without having to deal with the more involved BetheSalpeter formalism. |
A Toy Model For Single Field Open Inflation ; Inflation in an open universe produced by ColemanDe Luccia CDL tunneling induces a friction term that is strong enough to allow for successful smallfield inflation in models that would otherwise suffer from a severe overshoot problem. In this paper, we present a polynomial scalar potential which allows for a full analysis. This provides a simple model of singlefield open inflation on a smallfield inflection point after tunneling. We present numerical results and compare them with analytic approximations. |
Moving Object Trajectories MetaModel And SpatioTemporal Queries ; In this paper, a general moving object trajectories framework is put forward to allow independent applications processing trajectories data benefit from a high level of interoperability, information sharing as well as an efficient answer for a wide range of complex trajectory queries. Our proposed metamodel is based on ontology and event approach, incorporates existing presentations of trajectory and integrates new patterns like spacetime path to describe activities in geographical spacetime. We introduce recursive Region of Interest concepts and deal mobile objects trajectories with diverse spatiotemporal sampling protocols and different sensors available that traditional data model alone are incapable for this purpose. |
Deterministic POMDPs Revisited ; We study a subclass of POMDPs, called Deterministic POMDPs, that is characterized by deterministic actions and observations. These models do not provide the same generality of POMDPs yet they capture a number of interesting and challenging problems, and permit more efficient algorithms. Indeed, some of the recent work in planning is built around such assumptions mainly by the quest of amenable models more expressive than the classical deterministic models. We provide results about the fundamental properties of Deterministic POMDPs, their relation with ANDOR search problems and algorithms, and their computational complexity. |
Global Green Economy and Environmental Sustainability a Coopetitive Model ; This paper provides a coopetitive model for a global green economy, taking into account the environmental sustainability. In particular, we propose a differentiable coopetitive game G in the sense recently introduced by D. Carfi to represent a global green economy interaction, among a country c and the rest of the world w. Our game G is a linear parametric Euclidean perturbation of the classic Cournot duopoly. In the paper we offer the complete study of the proposed model and in particular a deep examination of its possible coopetitive solutions. |
Random coefficients bifurcating autoregressive processes ; This paper presents a model of asymmetric bifurcating autoregressive process with random coefficients. We couple this model with a Galton Watson tree to take into account possibly missing observations. We propose leastsquares estimators for the various parameters of the model and prove their consistency with a convergence rate, and their asymptotic normality. We use both the bifurcating Markov chain and martingale approaches and derive new important general results in both these frameworks. |
On the relativistic BGKBoltzmann model asymptotics and hydrodynamics ; The generalization of the BGK relaxation model to the special relativity setting is revisited here. We deal with several issues related to this relativistic kinetic model which seem to have been overlooked in the previous physical literature, including the unique determination of associated physical parameters, classical, ultrarelativistic and hydrodynamical limits, maximum entropy principles and the analysis of the linearized operator. |
Secondclass current effects from isospin breaking in tauomega pi nutau ; Secondclass weak currents can in the standard model be induced by chiral symmetry breaking. In the specific case of the decay tauomega pi nutau, dominated by the firstclass vector current with the rho quantum numbers, such effects would manifest themselves by small axial vector or, generally, nonvector contributions to the decay rate. We present an attempt to estimate such effects, based on a vector and axialvector dominance model of the relevant matrix elements supplemented by omegarho mixing. We also give an indication on the amplitude directly mediated by b11235omega pi, in principle also allowed in the standard model by isotopic spin violation. |
LHC Signals of NonCustodial Warped 5D Models ; We study the implications at the LHC for a recent class of noncustodial warped extradimensional models where the AdS5 metric is modified near the infrared brane. Such models allow for TeV KaluzaKlein excitations without conflict with electroweak precision tests. We discuss both the production of electroweak and strong KaluzaKlein gauge bosons. As we will show, only signals involving the third generation of quarks seem to be feasible in order to probe this scenario. |
Zero Curvature and generalization of Painleve equation from AKNSLundRegge model ; We explain the relation between the mixed mKdVsinhGordon model and the Kudryashov's equation. Then, we use the mixed AKNSLundRegge model to find a system of ODEs which is candidate to define a new transcendental function. We also applied the perturbative Painlev'e test and presented the local representation for the solution of the system. |
Estimation and Clustering with Infinite Rankings ; This paper presents a natural extension of stagewise ranking to the the case of infinitely many items. We introduce the infinite generalized Mallows model IGM, describe its properties and give procedures to estimate it from data. For estimation of multimodal distributions we introduce the ExponentialBlurringMeanShift nonparametric clustering algorithm. The experiments highlight the properties of the new model and demonstrate that infinite models can be simple, elegant and practical. |
ModelBased Bayesian Reinforcement Learning in Large Structured Domains ; Modelbased Bayesian reinforcement learning has generated significant interest in the AI community as it provides an elegant solution to the optimal explorationexploitation tradeoff in classical reinforcement learning. Unfortunately, the applicability of this type of approach has been limited to small domains due to the high complexity of reasoning about the joint posterior over model parameters. In this paper, we consider the use of factored representations combined with online planning techniques, to improve scalability of these methods. The main contribution of this paper is a Bayesian framework for learning the structure and parameters of a dynamical system, while also simultaneously planning a nearoptimal sequence of actions. |
NonAbelian Chiral 2Form and M5Branes ; We first review selfdual chiral gauge field theories by studying their Lorentz noncovariant and Lorentz covariant formulations. We next construct a nonAbelian selfdual twoform gauge theory in six dimensions with a spatial direction compactified on a circle. This model reduces to the YangMills theory in five dimensions for a small compactified radius R. The model also reduces to the Lorentzinvariant Abelian selfdual twoform theory when the gauge group is Abelian. The model is expected to describe multiple 5branes in Mtheory. We also discuss its decompactified limit, covariant formulation, BRSTantifield quantization and other generalizations. |
On topological restrictions of the spacetime in cosmology ; In this paper we discuss the restrictions of the spacetime for the standard model of cosmology by using results of the differential topology of 3 and 4manifolds. The smoothness of the cosmic evolution is the strongest restriction. The Poincare model dodecaeder model, the Picard horn and the 3torus are ruled out by the restrictions but a sum of two Poincare spheres is allowed. |
Quantifying SelfOrganization with Optimal Wavelets ; The optimal wavelet basis is used to develop quantitative, experimentally applicable criteria for selforganization. The choice of the optimal wavelet is based on the model of selforganization in the wavelet tree. The framework of the model is founded on the waveletdomain hidden Markov model and the optimal wavelet basis criterion for selforganization which assumes inherent increase in statistical complexity, the information content necessary for maximally accurate prediction of the system's dynamics. At the same time the method, presented here for the onedimensional data of any type, performs superior denoising and may be easily generalized to higher dimensions. |
Pareto Curves for Probabilistic Model Checking ; Multiobjective probabilistic model checking provides a way to verify several, possibly conflicting, quantitative properties of a stochastic system. It has useful applications in controller synthesis and compositional probabilistic verification. However, existing methods are based on linear programming, which limits the scale of systems that can be analysed and makes verification of timebounded properties very difficult. We present a novel approach that addresses both of these shortcomings, based on the generation of successive approximations of the Pareto curve for a multiobjective model checking problem. We illustrate dramatic improvements in efficiency on a large set of benchmarks and show how the ability to visualise Pareto curves significantly enhances the quality of results obtained from current probabilistic verification tools. |
Thermodynamic instabilities in dynamical quark models with complex conjugate mass poles ; We show that the CJT thermodynamic potential of dynamical quark models with a quark propagator represented by complex conjugate mass poles inevitably exhibits thermodynamic instabilities. We find that the minimal coupling of the quark sector to a Polyakov loop potential can strongly suppress but not completely remove such instabilities. This general effect is explicitly demonstrated in the framework of a covariant, chirally symmetric, effective quark model. |
A kinetic equation for spin polarized Fermi systems ; This paper a kinetic Boltzmann equation having a general type of collision kernel and modelling spindependent Fermi gases at low temperatures modelled by a kinetic equation of Boltzmann type. The distribution functions have values in the space of positive hermitean 2x2 complex matrices. Global existence of bounded weak solutions is proved in L1 to the initial value problem in a periodic box. |
Exact Solutions of Bianchi Types I and V Models in fR,T Gravity ; This paper is devoted to investigate the exact solutions of Bianchi types I and V spacetimes in the context of fR, T gravity 1. For this purpose, we found two exact solutions in each case by using assumption of constant deceleration parameter and the variation law of Hubble parameter. The obtained solutions correspond to two different models of this universe. The physical behavior of these models is also discussed. |
Geometry of HigherOrder Markov Chains ; We determine an explicit Grobner basis, consisting of linear forms and determinantal quadrics, for the prime ideal of Raftery's mixture transition distribution model for Markov chains. When the states are binary, the corresponding projective variety is a linear space, the model itself consists of two simplices in a crosspolytope, and the likelihood function typically has two local maxima. In the general nonbinary case, the model corresponds to a cone over a Segre variety. |
A StateDependent Polling Model with Markovian Routing ; A statedependent 1limited polling model with N queues is analyzed. The routing strategy generalizes the classical Markovian polling model, in the sense that two routing matrices are involved, the choice being made according to the state of the last visited queue. The stationary distribution of the position of the server is given. Ergodicity conditions are obtained by means of an associated dynamical system. Under rotational symmetry assumptions, average queue length and mean waiting times are computed. |
Algebraic Statistics in Model Selection ; We develop the necessary theory in computational algebraic geometry to place Bayesian networks into the realm of algebraic statistics. We present an algebrastatistics dictionary focused on statistical modeling. In particular, we link the notion of effiective dimension of a Bayesian network with the notion of algebraic dimension of a variety. We also obtain the independence and nonindependence constraints on the distributions over the observable variables implied by a Bayesian network with hidden variables, via a generating set of an ideal of polynomials associated to the network. These results extend previous work on the subject. Finally, the relevance of these results for model selection is discussed. |
Cosmological Models with a Varying Term in Lyra's Geometry ; Cosmological models in Lyra's geometry are constructed and investigated with the assumption of a minimal interaction of matter with the displacement vector field and the dynamical Lambda term. Exact solutions of the model equations are obtained for the different equations of state of the matter, that fills the universe, and for the certain assumptions on the decaying law for Lambda. |
A Note on SpatialTemporal Lattice Modeling and Maximum Likelihood Estimation ; Spatialtemporal linear model and the corresponding likelihoodbased statistical inference are important tools for the analysis of spatialtemporal lattice data. In this paper, we study the asymptotic properties of maximum likelihood estimates under a general asymptotic framework for spatialtemporal linear models. We propose mild regularity conditions on the spatialtemporal weight matrices and derive the asymptotic properties consistency and asymptotic normality of maximum likelihood estimates. A simulation study is conducted to examine the finitesample properties of the maximum likelihood estimates. |
Dynamics of Magnetized Bulk Viscous Strings in BransDicke Gravity ; We explore locally rotationally symmetric Bianchi I universe in BransDicke gravity with selfinteracting potential by using charged viscous cosmological string fluid. We use a relationship between the shear and expansion scalars and also take the power law for scalar field as well as selfinteracting potential. It is found that the resulting universe model maintains its anisotropic nature at all times due to the proportionality relationship between expansion and shear scalars. The physical implications of this model are discussed by using different parameters and their graphs. We conclude that this model corresponds to an accelerated expanding universe for particular values of the parameters. |
DBI Galileon and Late time acceleration of the universe ; We consider 13 dimensional maximally symmetric Minkowski brane embedded in a 14 dimensional maximally symmetric Minkowski background. The resulting 13 dimensional effective field theory is of DBI DiracBornInfeld Galileon type. We use this model to study the late time acceleration of the universe. We study the deviation of the model from the concordance Lambda CDM behaviour. Finally we put constraints on the model parameters using various observational data. |
Magnetic moments of the lowlying JP,12, 32 resonances within the framework of the chiral quark model ; The magnetic moments of the lowlying spinparity JP 12, 32 Lambda resonances, like, for example, Lambda1405 12, Lambda1520 32, as well as their transition magnetic moments, are calculated using the chiral quark model. The results found are compared with those obtained from the nonrelativistic quark model and those of unitary chiral theories, where some of these states are generated through the dynamics of two hadron coupled channels and their unitarization. |
An A4 x Z4 model for neutrino mixing ; The A4 x U1 flavor model of He, Keum, and Volkas is extended to provide a minimal modification to tribimaximal mixing that accommodates a nonzero reactor angle theta13 0.1. The sequestering problem is circumvented by forbidding superheavy scales and large coupling constants which would otherwise generate sizable RG flows. The model is compatible with but does not require a stable or metastable dark matter candidate in the form of a complex scalar field with unit charge under a discrete subgroup Z4 of the U1 flavor symmetry. |
General method for finding ground state manifold of classical Heisenberg model ; We investigate classical Heisenberg models with the translation symmetries of infinite crystals. We prove a spiral theorem, which states that under certain conditions there must exist spiral ground states, and propose a natural classification of all manageable models based on some spectral properties, which are directly related to their ground state manifolds. We demonstrate how the ground state manifold can be calculated analytically for all spectra with finite number of minima and some with extensive minima, and algorithmically for the others. We also extend the method to particular anisotropic interactions. |
Cosmic Evolution in Fractional Action Cosmology ; For the fractional action cosmological model, derived earlier by the author from the variational principle for a fractional action functional, the exact solutions are obtained. The case of a quasi vacuum state of matter that fills the universe is considered. Moreover, on the basis of specific ansatz proposed in this paper for the cosmological term, the class of exact solutions of the model equations is obtained. Examples for some given laws of the cosmological term evolution are provided. Besides, a formula for the effective equation of state is derived, and the deceleration parameter of the obtained models is studied. |
Coordination Level Modeling and Analysis of Parallel Programs using Petri Nets ; In the last fifteen years, the high performance computing HPC community has claimed for parallel programming environments that reconciles generality, higher level of abstraction, portability, and efficiency for distributedmemory parallel computing platforms. The Hash component model appears as an alternative for addressing HPC community claims for fitting these requirements. This paper presents foundations that will enable a parallel programming environment based on the Hash model to address the problems of debugging, performance evaluation and verification of formal properties of parallel program by means of a powerful, simple, and widely adopted formalism Petri nets. |
Perfect Fluid Quantum Anisotropic Universe Merits and Challenges ; The present paper deals with quantization of perfect fluid anisotropic cosmological models. Bianchi type V and IX models are discussed following Schutz's method of expressing fluid velocities in terms of six potentials. The wave functions are found for several examples of equations of state. In one case a complete wave packet could be formed analytically. The initial singularity of a zero proper volume can be avoided in this case, but it is plagued by the usual problem of nonunitarity of anisotropic quantum cosmological models. It is seen that a particular operator ordering alleviates this problem. |
Identifying dynamical systems with bifurcations from noisy partial observation ; Dynamical systems are used to model a variety of phenomena in which the bifurcation structure is a fundamental characteristic. Here we propose a statistical machinelearning approach to derive lowdimensional models that automatically integrate information in noisy timeseries data from partial observations. The method is tested using artificial data generated from two cellcycle control system models that exhibit different bifurcations, and the learned systems are shown to robustly inherit the bifurcation structure. |
Realistic Cyclic Magnetic Universe ; This work presents a complete cyclic cosmological scenario based on nonlinear magnetic field. It is constructed a model composed by five fluids namely baryonic matter, dark matter, radiation, neutrinos and a cosmological magnetic field. The first four fluids are treated in the standard way and the fifth fluid, the magnetic field, is described by a nonlinear electrodynamics. The free parameters are fitted by observational data SNIa, CMB, extragalactic magnetic fields, etc and by simple theoretical considerations. As result arises a cyclic cosmological model which preserves the main successes of standard big bang model and solve some other problems like the initial singularity, the present acceleration and the Big Rip. |
Resolution of dark matter problem in fT gravity ; In this paper, we attempt to resolve the dark matter problem in fT gravity. Specifically, from our model we successfully obtain the flat rotation curves of galaxies containing dark matter. Further, we obtain the density profile of dark matter in galaxies. Comparison of our analytical results shows that our torsionbased toy model for dark matter is in good agreement with empirical databased models. It shows that we can address the dark matter as an effect of torsion of the space. |
On the age, time and migration dependent dynamics of diseases ; This paper generalizes a previously published differential equation that describes the relation between the agespecific incidence, remission, and mortality of a disease with its prevalence. The underlying model is a simple compartment model with three states illnessdeath model. In contrast to the former work, migration and calendar timeeffects are included. As an application of the theoretical findings, a hypothetical example of an irreversible disease is treated. |
A Physical Source of Dark Energy and Dark Matter ; A physical mechanism that produces three energy components is proposed as the common origin of dark energy and dark matter. The first two have equations of state W 0 and act like dark matter, while the last has W 1 at low redshifts making it a candidate for dark energy. These are used to model the supernovae Union2 data resulting in a curve fitting identical to the LAMBDACDM model. This model opens new avenues for Cosmology research and implies a reinterpretation of the dark components as a scalar field stored in the metric of spacetime. |
Probability Distribution Function of the Order Parameter Mixing Fields and Universality ; We briefly review the use of the order parameter probability distribution function as a useful tool to obtain the critical properties of statistical mechanical models using computer Monte Carlo simulations. Some simple discrete spin magnetic systems on a lattice, such as Ising, general spinS BlumeCapel and BaxterWu, Qstate Potts, among other models, will be considered as examples. The importance and the necessity of the role of mixing fields in asymmetric magnetic models will be discussed in more detail, as well as the corresponding distributions of the extensive conjugate variables. |
31dimensional expanding universe from a Lorentzian matrix model for superstring theory in 91dimensions ; We study the Lorentzian version of the type IIB matrix model as a nonperturbative formulation of superstring theory in 91dimensions. Monte Carlo results show that not only space but also time emerges dynamically in this model. Furthermore, the realtime dynamics extracted from the matrices turns out to be remarkable 3 out of 9 spatial directions start to expand at some critical time. This can be interpreted as the birth of our Universe. |
Noether symmetry of FT cosmology with quintessence and phantom scalar fields ; In this paper, we investigate the Noether symmetries of FT cosmology involving matter and dark energy. In this model, the dark energy is represented by a canonical scalar field with a potential. Two special cases for dark energy are considered including phantom energy and quintessence. We obtain FTsim T34, and the scalar potential Vphisimphi2 for both models of dark energy and discuss quantum picture of this model. Some astrophysical implications are also discussed. |
Bethe vectors of GL3invariant integrable models ; We study SU3invariant integrable models solvable by nested algebraic Bethe ansatz. Different formulas are given for the Bethe vectors and the actions of the generators of the Yangian Ysl3 on Bethe vectors are considered. These actions are relevant for the calculation of correlation functions and form factors of local operators of the underlying quantum models. |
QED with chiral nonminimal coupling aspects of the Lorentzviolating quantum corrections ; An effective model for QED with the addition of a nonminimal coupling with a chiral character is investigated. This term, which is proportional to a fixed 4vector bmu, violates Lorentz symmetry and may originate a CPTeven Lorentz breaking term in the photon sector. It is shown that this Lorentz breaking CPTeven term is generated and that,in addition, the chiral nonminimal coupling requires this term is present from the beginning. The nonrenormalizability of the model is invoked in the discussion of this fact and the result is confronted with the one from a model with a Lorentzviolating nonminimal coupling without chirality. |
Breathers and their interaction in the massless GrossNeveu model ; The breather is a vibrating multifermion bound state of the massless GrossNeveu model, originally found by Dashen, Hasslacher and Neveu in the large N limit. We exhibit the salient features of this state and confirm that it solves the relativistic timedependent HartreeFock equations. We then solve the scattering problem of two breathers with arbitrary internal parameters and velocities, generalizing an ansatz recently developed for the baryonbaryon scattering problem in the same model. The exact analytical solution is given and illustrated with a few examples. |
A new perspective on cosmology in Loop Quantum Gravity ; We present a new cosmological model derived from Loop Quantum Gravity. The formulation is based on a projection of the kinematical Hilbert space of the full theory down to a subspace representing the proper arena for an inhomogeneous Bianchi I model. This procedure gives a direct link between the full theory and its cosmological sector. The emerging quantum cosmological model represents a simplified arena on which the complete canonical quantization program can be tested. The achievements of this analysis could also shed light on Loop Quantum Cosmology and its relation with the full theory. |
Cosmological parameters from the thermodynamic model of gravity ; Within our recent thermodynamic model of gravity the dark energy is identified with the energy of collective gravitational interactions of all particles in the universe, which is missing in the standard treatments. For a simple model universe composed of neutral and charged particles of identical mass we estimate the radiation, baryon and dark energy densities and obtain the values which are very close to the current cosmological observations. |
Dynamic fluctuations in unfrustrated systems random walks, scalar fields and the KosterlitzThouless phase ; We study analytically the distribution of fluctuations of the quantities whose average yield the usual twopoint correlation and linear response functions in three unfrustrated models the random walk, the d dimensional scalar field and the 2d XY model. In particular we consider the time dependence of ratios between composite operators formed with these fluctuating quantities which generalize the largely studied fluctuationdissipation ratio, allowing us to discuss the relevance of the effective temperature notion beyond linear order. The behavior of fluctuations in the aforementioned solvable cases is compared to numerical simulations of the 2d clock model with p6,12 states. |
Presence of anisotropic pressures in LemaitreTolmanBondi cosmological models ; We describe LemaitreTolmanBondi cosmological models where an anisotropic pressures is considered. By using recent astronomical observations coming from supernova of Ia types we constraint the values of the parameters that characterize our models. |
Experimental search for a Lorentz invariant spacetime granularity Possibilities and bounds ; We consider a search for phenomenological signatures from an hypothetical spacetime granularity that respects Lorentz invariance. The model is based on the idea that the metric description of Einstein's gravity corresponds to a hydrodynamic characterization of some deeper underlying structure, and that Einstein's gravity is thus to be seen as emergent. We present the specific phenomenological model in detail and analyze the bounds on its free parameters established by a experiment specifically designed to test this model. |
Modified gravity theories and dark matter models tested by galactic rotation curves ; BoseEinstein condensate dark matter model and RandallSundrum type 2 braneworld theory are tested with galactic rotation curves. Analytical expressions are derived for the rotational velocities of test particles around the galactic center in both cases. The velocity profiles are fitted to the observed rotation curve data of high surface brightness and low surface brightness galaxies. The braneworld model fits better the rotation curves with asymptotically flat behaviour. |