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Boosted Tops from Gluino Decays ; Naturalness considerations, together with the nonobservation of superpartners of the Standard Model particles at the Large Hadron Collider LHC so far, favor supersymmetric SUSY models in which third generation squarks are significantly lighter than those of the first two generations. In such models, gluino pairproduction is typically the dominant SUSY production process at the LHC, and it often leads to final states with multiple top quarks. Some of these top quarks may be relativistic in the lab frame, in which case their hadronic decays may produce top jets. We propose that the recently developed techniques for tagging top jets can be used to boost sensitivity of the LHC searches for this scenario. For example, within the simplified model used for this study, we estimate that a search with 2 toptagged jets can probe gluino masses of up to about 1 TeV at the 7 TeV LHC with 30 inverse fb integrated luminosity.

Meanfield models with shortrange correlations ; Given an arbitrary finite dimensional Hamiltonian H0, we consider the model HH0Delta H, where Delta H is a generic fully connected interaction. By using the strong law of large numbers we easily prove that, for all such models, a generalized CurieWeiss meanfield equation holds. Unlike traditional meanfield models the term H0 gives rise to shortrange correlations and, furthermore, when H0 has negative couplings, firstorder phase transitions and inverse transition phenomena may take place even when only twobody interactions are present. The dependence from a non uniform external field and finite size effects are also explicitly calculated. Partially, these results were derived long ago by using minmax principles but remained almost unknown.

Stability analysis of agegraphic dark energy in BransDicke cosmology ; Stability analysis of agegraphic dark energy in BransDicke theory is presented in this paper. We constrain the model parameters with the observational data and thus the results become broadly consistent with those expected from experiment. Stability analysis of the model without best fitting shows that universe may begin from an unstable state passing a saddle point and finally become stable in future. However, with the best fitted model, There is no saddle intermediate state. The agegraphic dark energy in the model by itself exhibits a phantom behavior. However, contribution of cold dark matter on the effective energy density modifies the state of teh universe from phantom phase to quintessence one. The statefinder diagnosis also indicates that the universe leaves an unstable state in the past, passes the LCDM state and finally approaches the sable state in future.

Quarkhadron phase transition in a chameleon BransDicke model of brane gravity ; In this work, the quarkhadron phase transition in a chameleon BransDicke model of brane world cosmology within an effective model of QCD is investigated. Whereas, in the chameleon BransDicke model of brane world cosmology, the Friedmann equation and conservation of density energy are modified, resulting in an increased expansion in the early Universe. These have important effects on quarkhadron phase transitions. We investigate the evolution of the physical quantities relevant to quantitative descriptions of the early times, namely, the energy density, rho, temperature, T, and the scale factor, a, before, during, and after the phase transition. We do this for smooth crossover formalism in which lattice QCD data is used for obtaining the matter equation of state and first order phase transition formalism. Our analyses show that the quarkhadron phase transition has occurred at approximately one nanosecond after the big bang and the general behavior of temperature is similar in both of two approaches.

Homotopy weighted colimits ; Let V be a cofibrantly generated closed symmetric monoidal model category and M a model Vcategory. We say that a weighted colimit WD of a diagram D weighted by W is a homotopy weighted colimit if the diagram D is pointwise cofibrant and the weight W is cofibrant in the projective model structure on Cop,V. We then proceed to describe such homotopy weighted colimits through homotopy tensors and ordinary conical homotopy colimits. This is a homotopy version of the well known isomorphism WDintCWtensor D. After proving this homotopy decomposition in general we study in some detail a few special cases. For simplicial sets tensors may be replaced up to weak equivalence by conical homotopy colimits and thus the weighted homotopy colimits have no added value. The situation is completely different for model dgcategories where the desuspension cannot be constructed from conical homotopy colimits. In the last section we characterize those Vfunctors inducing a Quillen equivalence on the enriched presheaf categories.

Semigroup Identities, Proofs, and Artificial Intelligence ; It is known that if every group satisfying an identity of the form yx xUx,yy is abelian, so is every semigroup that satisfies that identity. Because a group has an identity element and the cancellation property, it is easier to show that a group is abelian than that a semigroup is. If we know that it is, then there must be a sequence of substitutions using xUx,yy yx that transforms xy to yx. We examine such sequences and propose finding them as a challenge to proof by computer. Also, every model of y xUx,yx is a group. This raises a similar challenge, which we explore in the special case y xmypxn. In addition we determine the free model with two generators of some of these identities. In particular, we find that the free model for y x2yx2 has order 32 and is the product of D4 the symmetries of a square, C2, and C2, and point out relations between such identities and Burnside's Problem concerning models of xn e.

Derivativebased global sensitivity measures general links with Sobol' indices and numerical tests ; The estimation of variancebased importance measures called Sobol' indices of the input variables of a numerical model can require a large number of model evaluations. It turns to be unacceptable for highdimensional model involving a large number of input variables typically more than ten. Recently, Sobol and Kucherenko have proposed the Derivativebased Global Sensitivity Measures DGSM, defined as the integral of the squared derivatives of the model output, showing that it can help to solve the problem of dimensionality in some cases. We provide a general inequality link between DGSM and total Sobol' indices for input variables belonging to the class of Boltzmann probability measures, thus extending the previous results of Sobol and Kucherenko for uniform and normal measures. The special case of logconcave measures is also described. This link provides a DGSMbased maximal bound for the total Sobol indices. Numerical tests show the performance of the bound and its usefulness in practice.

Note on RIPbased Cosparse Analysis ; Over the past years, there are increasing interests in recovering the signals from undersampling data where such signals are sparse under some orthogonal dictionary or tight framework, which is referred to be sparse synthetic model. More recently, its counterpart, i.e., the sparse analysis model, has also attracted researcher's attentions where many practical signals which are sparse in the truly redundant dictionary are concerned. This short paper presents important complement to the results in existing literatures for treating sparse analysis model. Firstly, we give the natural generalization of wellknown restricted isometry property RIP to deal with sparse analysis model, where the truly arbitrary incoherent dictionary is considered. Secondly, we studied the theoretical guarantee for the accurate recovery of signal which is sparse in general redundant dictionaries through solving l1norm sparsitypromoted optimization problem. This work shows not only that compressed sensing is viable in the context of sparse analysis, but also that accurate recovery is possible via solving l1minimization problem.

Charmed and strange baryon resonances with heavyquark spin symmetry ; We study charmed and strange baryon resonances that are generated dynamically by a unitary baryonmeson coupledchannel model which incorporates heavyquark spin symmetry. This is accomplished by extending the SU3 WeinbergTomozawa chiral Lagrangian to SU8 spinflavor symmetry plus a suitable symmetry breaking. The model produces resonances with negative parity from swave interaction of pseudoscalar and vector mesons with 12 and 32 baryons. Resonances in all the isospin, spin, and strange sectors with one, two, and three charm units are studied. Our results are compared with experimental data from several facilities, such as the CLEO, Belle or BaBar Collaborations, as well as with other theoretical models. Some of our dynamically generated states can be readily assigned to resonances found experimentally, while others do not have a straightforward identification and require the compilation of more data and also a refinement of the model. In particular, we identify the Xic2790 and Xic2815 resonances as possible candidates for a heavyquark spin symmetry doublet.

Gauge Fluxes in Ftheory and Type IIB Orientifolds ; We provide a detailed correspondence between G4 gauge fluxes in Ftheory compactifications with SUn and SUnx1 gauge symmetry and their Type IIB orientifold limit. Based on the resolution of the relevant Ftheory Tate models we classify the factorisable G4fluxes and match them with the set of universal D5tadpole free U1fluxes in Type IIB. Where available, the global version of the universal spectral cover flux corresponds to Type IIB gauge flux associated with a massive diagonal U1. In U1restricted Tate models extra massless abelian fluxes exist which are associated with specific linear combinations of Type IIB fluxes. Key to a quantitative match between Ftheory and Type IIB is a proper treatment of the conifold singularity encountered in the Sen limit of generic Ftheory models. We also shed further light on the brane recombination process relating generic and U1restricted Tate models.

In connection with identification of VLF emissions before L'Aquila earthquake ; The present paper deals with an attempt to check up the theoretical model of selfgenerated seismoelectromagnetic oscillations of LAI system on the basis of retrospective data. Application of the offered simple model enables one to explain qualitatively the mechanism of VLF electromagnetic emission initiated in the process of an earthquake preparation. It is worth to pay attention to the fact that frequency changes from MHz to kHz in electromagnetic emission spectrum comes to a good agreement with avalanchelike unstable model of fault formation. L'Aquila earthquake taken as an example to isolate reliably the Earth VLF emission from the magnetospheric electromagnetic emission of the same frequency range, MHD criterion is offered together with geomagnetic activity indexes. On the basis of the considered three earthquakes, according to the opinion of authors the model of selfgenerated seismoelectromagnetic oscillations of the LAI system will enable us to approach the problem of resolution of earthquake prediction by certain accuracy.

The method of moments and degree distributions for network models ; Probability models on graphs are becoming increasingly important in many applications, but statistical tools for fitting such models are not yet well developed. Here we propose a general method of moments approach that can be used to fit a large class of probability models through empirical counts of certain patterns in a graph. We establish some general asymptotic properties of empirical graph moments and prove consistency of the estimates as the graph size grows for all ranges of the average degree including Omega1. Additional results are obtained for the important special case of degree distributions.

Mining Education Data to Predict Student's Retention A comparative Study ; The main objective of higher education is to provide quality education to students. One way to achieve highest level of quality in higher education system is by discovering knowledge for prediction regarding enrolment of students in a course. This paper presents a data mining project to generate predictive models for student retention management. Given new records of incoming students, these predictive models can produce short accurate prediction lists identifying students who tend to need the support from the student retention program most. This paper examines the quality of the predictive models generated by the machine learning algorithms. The results show that some of the machines learning algorithms are able to establish effective predictive models from the existing student retention data.

Hybrid GenerativeDiscriminative Learning for Automatic Image Annotation ; Automatic image annotation AIA raises tremendous challenges to machine learning as it requires modeling of data that are both ambiguous in input and output, e.g., images containing multiple objects and labeled with multiple semantic tags. Even more challenging is that the number of candidate tags is usually huge as large as the vocabulary size yet each image is only related to a few of them. This paper presents a hybrid generativediscriminative classifier to simultaneously address the extreme dataambiguity and overfittingvulnerability issues in tasks such as AIA. Particularly 1 an ExponentialMultinomial Mixture EMM model is established to capture both the input and output ambiguity and in the meanwhile to encourage prediction sparsity; and 2 the prediction ability of the EMM model is explicitly maximized through discriminative learning that integrates variational inference of graphical models and the pairwise formulation of ordinal regression. Experiments show that our approach achieves both superior annotation performance and better tag scalability.

fR Gravity from the renormalisation group ; We explore the cosmological dynamics of an effective fR model constructed from a renormalisation group RG improvement of the EinsteinHilbert action, using the nonperturbative beta functions of the exact renormalisation group equation. The resulting fR model has some remarkable properties. It naturally exhibits an unstable de Sitter era in the ultraviolet UV, dynamically connected to a stable de Sitter era in the IR, via a period of radiation and matter domination, thereby describing a nonsingular universe. We find that the UV de Sitter point is one of an infinite set, which make the UV RG fixed point inaccessible to classical cosmological evolution. In the vicinity of the fixed point, the model behaves as R2 gravity, while it correctly recovers General Relativity at solar system scales. In this simplified model, the fluctuations are too large to be the observed ones, and more ingredients in the action are needed.

Turing machines can be efficiently simulated by the General Purpose Analog Computer ; The ChurchTuring thesis states that any sufficiently powerful computational model which captures the notion of algorithm is computationally equivalent to the Turing machine. This equivalence usually holds both at a computability level and at a computational complexity level modulo polynomial reductions. However, the situation is less clear in what concerns models of computation using real numbers, and no analog of the ChurchTuring thesis exists for this case. Recently it was shown that some models of computation with real numbers were equivalent from a computability perspective. In particular it was shown that Shannon's General Purpose Analog Computer GPAC is equivalent to Computable Analysis. However, little is known about what happens at a computational complexity level. In this paper we shed some light on the connections between this two models, from a computational complexity level, by showing that, modulo polynomial reductions, computations of Turing machines can be simulated by GPACs, without the need of using more space resources than those used in the original Turing computation, as long as we are talking about bounded computations. In other words, computations done by the GPAC are as spaceefficient as computations done in the context of Computable Analysis.

A hostparasite model for a twotype cell population ; A hostparasite model is considered for a population of cells that can be of two types, A or B, and exhibits unilateral reproduction while a Bcell always splits into two cells of the same type, the two daughter cells of an Acell can be of any type. The random mechanism that describes how parasites within a cell multiply and are then shared into the daughter cells is allowed to depend on the hosting mother cell as well as its daughter cells. Focusing on the subpopulation of Acells and its parasites, the model differs from the singletype model recently studied by Bansaye 2008 in that the sharing mechanism may be biased towards one of the two types. Main results are concerned with the nonextinctive case and provide information on the behavior, as ntoinfty, of the number Aparasites in generation n and the relative proportion of A and Bcells in this generation which host a given number of parasites. As in Bansaye,2008, proofs will make use of a socalled random cell line which, when conditioned to be of type A, behaves like a branching process in random environment.

Solvable Kessence Cosmologies and Modified Chaplygin Gas Unified Models of Dark Energy and Dark Matter ; This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable kessence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the parameter n. The graphical behavior of these equations are also discussed by using power law form of potential. The relationship between kessence and modified Chaplygin gas model shows viable results in the dark energy scenario. We conclude that the universe behaves as a cosmological constant, quintessence phase or phantom phase depending upon n.

Parametrised modified gravity and the CMB Bispectrum ; We forecast the constraints on modified theories of gravity from the cosmic microwave background CMB anisotropies bispectrum that arises from correlations between lensing and the Integrated SachsWolfe effect. In models of modified gravity the evolution of the metric potentials is generally altered and the contribution to the CMB bispectrum signal can differ significantly from the one expected in the standard cosmological model.We adopt a parametrised approach and focus on three different classes of models Linder's growth index, Chameleontype models and fR theories. We show that the constraints on the parameters of the models will significantly improve with future CMB bispectrum measurements.

Accelerating Bianchi TypeV Cosmology with Perfect Fluid and Heat Flow in SaezBallester Theory ; In this paper we discuss the law of variation of scale factor a tketfrac1n which yields a timedependent deceleration parameter DP representing a new class of models that generate a transition of universe from the early decelerated phase to the recent accelerating phase. Exact solutions of Einstein's modified field equations with perfect fluid and heat conduction are obtained within the framework of SaezBallester scalartensor theory of gravitation and the model is found to be in good agreement with recent observations. We find, for n 3, k 1, the present value of DP in derived model as q0 0.67 which is very near to the observed value of DP at present epoch. We find that the timedependent DP is sensible for the present day Universe and give an earmark description of evolution of universe. Some physical and geometric properties of the models are also discussed.

Efficient cache oblivious algorithms for randomized divideandconquer on the multicore model ; In this paper we present randomized algorithms for sorting and convex hull that achieves optimal performance for speedup and cache misses on the multicore model with private cache model. Our algorithms are cache oblivious and generalize the randomized divide and conquer strategy given by Reischuk and Reif and Sen. Although the approach yielded optimal speedup in the PRAM model, we require additional techniques to optimize cachemisses in an oblivious setting. Under a mild assumption on input and number of processors our algorithm will have optimal time and cache misses with high probability. Although similar results have been obtained recently for sorting, we feel that our approach is simpler and general and we apply it to obtain an optimal parallel algorithm for 3D convex hulls with similar bounds. We also present a simple randomized processor allocation technique without the explicit knowledge of the number of processors that is likely to find additional applications in resource oblivious environments.

Generalized Berreman's model of the elastic surface free energy of a nematic liquid crystal on a sawtoothed substrate ; In this paper we present a generalization of Berreman's model for the elastic contribution to the surface freeenergy density of a nematic liquid crystal in presence of a sawtooth substrate which favours homeotropic anchoring, as a function of the wavenumber of the surface structure q, the tilt angle alpha and the surface anchoring strength w. In addition to the previously reported nonanalytic contribution proportional to qln q, due to the nucleation of disclination lines at the wedge bottoms and apexes of the substrate, the nexttoleading contribution is proportional to q for a given substrate roughness, in agreement with Berreman's predictions. We characterise this term, finding that it has two contributions the deviations of the nematic director field with respect to the corresponding to the isolated disclination lines, and their associated core free energies. Comparison with the results obtained from the Landaude Gennes model shows that our model is quite accurate in the limit wL1, when strong anchoring conditions are effectively achieved.

Three Generations in Minimally Extended Standard Models ; We present a class of minimally extended standard models with the gauge group SU3C times SUNL times U1X where for all N geq 3, anomaly cancelation requires three generations. At low energy, we recover the Standard Model SM, while at higher energies, there must exist quarks, leptons and gauge bosons with electric charges shifted from their SM values by integer multiples of the electron charge up to pm N2 e. Since the value N5 is the highest N consistent with QCD asymptotic freedom, we elaborate on the 351 model.

Selfexciting point process modeling of conversation event sequences ; Selfexciting processes of Hawkes type have been used to model various phenomena including earthquakes, neural activities, and views of online videos. Studies of temporal networks have revealed that sequences of social interevent times for individuals are highly bursty. We examine some basic properties of event sequences generated by the Hawkes selfexciting process to show that it generates bursty interevent times for a wide parameter range. Then, we fit the model to the data of conversation sequences recorded in company offices in Japan. In this way, we can estimate relative magnitudes of the self excitement, its temporal decay, and the base event rate independent of the self excitation. These variables highly depend on individuals. We also point out that the Hawkes model has an important limitation that the correlation in the interevent times and the burstiness cannot be independently modulated.

Evidence for departure from CDM with LSS ; We investigate the growth index parameter gamma and the time variation of the gravitational constant Geff by using the currently available growth function fz data at different redshifts, with and without scaling to the fiducial Lambda CDM model. We inquire the four different models of gamma including a constant gamma. From a chi2 minimization, we constrain the parameter spaces of models and show that Lambda CDM model is excluded by 1sigma level from current fz data. Geff is different from the Newton's gravitational constant GN in modified gravity theories and interestingly, the current data shows that Geff neq GN at z gtrsim 0.2 sim 0.3 at 3sigma level. From these, we conclude that Einstein's General Relativity with Lambda CDM is ruled out by 99 confidence level from large scale structure observations.

Structure Formation in Modified Gravity Scenarios ; We study the growth of structures in modified gravity models where the Poisson equation and the relationship between the two Newtonian potentials are modified by explicit functions of space and time. This parameterisation applies to the fR models and more generally to screened modified gravity models. We investigate the linear and weakly nonlinear regimes using the standard perturbative approach and a resummation technique, while we use the spherical dynamics to go beyond loworder results. This allows us to estimate the matter density power spectrum and bispectrum from linear to highly nonlinear scales, the full probability distribution of the density contrast on weakly nonlinear scales, and the halo mass function. We analyse the impact of modifications of gravity on these quantities for a few realistic models. In particular, we find that the standard oneloop perturbative approach is not sufficiently accurate to probe these effects on the power spectrum and it is necessary to use resummation methods even on weakly nonlinear scales which provide the best observational window for modified gravity as relative deviations from General Relativity do not grow significantly on smaller scales where theoretical predictions become increasingly difficult.

Congestion Games on Weighted Directed Graphs, with Applications to Spectrum Sharing ; With the advance of complex largescale networks, it is becoming increasingly important to understand how selfish and spatially distributed individuals will share network resources without centralized coordinations. In this paper, we introduce the graphical congestion game with weighted edges GCGWE as a general theoretical model to study this problem. In GCGWE, we view the players as vertices in a weighted graph. The amount of negative impact e.g. congestion caused by two closeby players to each other is determined by the weight of the edge linking them. The GCGWE unifies and significantly generalizes several simpler models considered in the previous literature, and is well suited for modeling a wide range of networking scenarios. One good example is to use the GCGWE to model spectrum sharing in wireless networks, where we can properly define the edge weights and payoff functions to capture the rather complicated interference relationship between wireless nodes. By identifying which GCGWEs possess pure Nash equilibria and the very desirable finite improvement property, we gain insight into when spatially distributed wireless nodes will be able to selforganize into a mutually acceptable resource allocation. We also consider the efficiency of the pure Nash equilibria, and the computational complexity of finding them.

Nonextensive local composition models in theories of solutions ; Thermodynamic models present binary interaction parameters, based on the Boltzmann weight. Discrepancies from experimental data lead to empirically consider temperature dependence of the parameters, but these modifications keep unchanged the exponential nature of the equations. We replace the Boltzmann weight by the nonextensive Tsallis weight, and generalize three models for nonelectrolyte solutions that use the local composition hypothesis, namely Wilson's, NRTL, and UNIQUAC models. The proposed generalizations present a nonexponential dependence on the temperature, and relies on a theoretical basis of nonextensive statistical mechanics. The qmodels present one extra binary parameter qij, that recover the original cases in the limit qij to 1. Comparison with experimental data is illustrated with two examples of the activity coefficient of ethanol, infinitely diluted in toluene, and in decane.

Generalized selfdual MaxwellChernSimonsHiggs model ; We present a consistent BPS framework for a generalized MaxwellChernSimonsHiggs model. The overall model, including its selfdual potential, depends on three different functions, hphi,N, wphi and Gphi, which are functions of the scalar fields only. The BPS energy is proportional to the magnetic flux when wphi and Gphi are related to each other by a differential constraint. We present an explicit nonstandard model and its topologically nontrivial static configurations, which are described by the usual radially symmetric profile. Finally, we note that the nonstandard results behave in a similar way as their standard counterparts, as expected, reinforcing the consistence of the overall construction.

A derivation of the master equation from path entropy maximization ; The master equation and, more generally, Markov processes are routinely used as models for stochastic processes. They are often justified on the basis of randomization and coarsegraining assumptions. Here instead, we derive nth order Markov processes and the master equation as unique solutions to an inverse problem. In particular, we find that when the constraints are not enough to uniquely determine the stochastic model, the nth order Markov process emerges as the unique maximum entropy solution to this otherwise underdetermined problem. This gives a rigorous alternative for justifying such models while providing a systematic recipe for generalizing widely accepted stochastic models usually assumed to follow from first principles.

Strong electroweak symmetry breaking or, if no SM Higgs, then what ; While the LHC takes on the challenge of experimentally exploring the electroweak symmetry breaking sector, it is not only interesting but also crucial to explore alternatives to the Standard Model scenario with an elementary scalar Higgs boson. The idea of electroweak symmetry breaking by some new strong dynamics is discussed. A simple, general and selfconsistent low energy effective description of Higgsless models is introduced. This effective theory is studied from the point of view of prolonging perturbative unitarity of WW scattering by spin1 resonances originating from the strongly interacting sector. The LHC phenomenology and the discovery potential for these spin1 resonances is also discussed. The role of spin1 resonances is then considered on the grounds of composite Higgs models. A general prescription for the explicit inclusion of such resonances in the effective Lagrangian description of these models is presented.

Scalar Material Reference Systems and Loop Quantum Gravity ; In the past, the possibility to employ scalar material reference systems in order to describe classical and quantum gravity directly in terms of gauge invariant Dirac observables has been emphasised frequently. This idea has been picked up more recently in Loop Quantum Gravity LQG with the aim to perform a reduced phase space quantisation of the theory thus possibly avoiding problems with the Dirac operator constraint quantisation method for constrained system. In this work, we review the models that have been studied on the classical andor the quantum level and parametrise the space of theories so far considered. We then describe the quantum theory of a model that, to the best of our knowledge, so far has only been considered classically. This model could arguably called the optimal one in this class of models considered as it displays the simplest possible true Hamiltonian while at the same time reducing all constraints of General Relativity.

A Complete Model of LowScale Gauge Mediation ; Recent signs of a Standard Modellike Higgs at 125 GeV point towards large Aterms in the MSSM. This presents special challenges for gauge mediation, which by itself predicts vanishing Aterms at the messenger scale. In this paper, we review the general problems that arise when extending gauge mediation to achieve large Aterms, and the mechanisms that exist to overcome them. Using these mechanisms, we construct weaklycoupled models of lowscale gauge mediation with extended Higgsmessenger couplings that generate large Aterms at the messenger scale and viable muBmuterms. Our models are simple, economical, and complete realizations of supersymmetry at the weak scale.

Unification of the standard and gradient theories of phase transition ; We show, that the standard model of phase transition can be unified with the gradient model of phase transitions using the description in terms of the gradient of order parameter. The generalization of the gradient theory of phase transitions with regard to the fourth power of the order parameter and its gradient is proposed. Such generalization makes it possible to described wide class of phase transitions within a unified approach. In particular it is consistent with the nonlinear models, that can be used to describe a phase transition with the formation of spatially inhomogeneous distribution of the order parameter. Typical examples of such structures with or without defects are considered. We show that formation of spatially inhomogeneous distributions of the order parameter in the course of a phase transitions is a characteristic feature of many nonlinear models of phase transitions.

Separable potential model for mesonbaryon interaction beyond the Swave ; A model for lowenergy mesonbaryon interaction in the strange sector is presented. The interaction is described in terms of separable potentials with multiple partial waves considered. A general solution of LippmannSchwinger equation for the scattering of spin zero and spin onehalf particles is derived. Next, the general framework is applied to the barKN sector in a simple model with only the S and Pwaves taken into account. The separable potential is designed to match the chiral perturbation theory at lowest nontrivial order. It is shown that although a simple model with three free parameters works well for the Swave, it fails to reproduce the Pwave features of kaonnucleon physics. Most importantly, the Pwave interaction is too weak to express a resonant behavior that could be identified as Sigma1385 resonance.

Exact fielddriven interface dynamics in the twodimensional stochastic Ising model with helicoidal boundary conditions ; We investigate the interface dynamics of the twodimensional stochastic Ising model in an external field under helicoidal boundary conditions. At sufficiently low temperatures and fields, the dynamics of the interface is described by an exactly solvable highspin asymmetric quantum Hamiltonian that is the infinitesimal generator of the zero range process. Generally, the critical dynamics of the interface fluctuations is in the KardarParisiZhang universality class of critical behavior. We remark that a whole family of RSOS interface models similar to the Ising interface model investigated here can be described by exactly solvable restricted highspin quantum XXZtype Hamiltonians.

The Minimum Information Principle for Discriminative Learning ; Exponential models of distributions are widely used in machine learning for classiffication and modelling. It is well known that they can be interpreted as maximum entropy models under empirical expectation constraints. In this work, we argue that for classiffication tasks, mutual information is a more suitable information theoretic measure to be optimized. We show how the principle of minimum mutual information generalizes that of maximum entropy, and provides a comprehensive framework for building discriminative classiffiers. A game theoretic interpretation of our approach is then given, and several generalization bounds provided. We present iterative algorithms for solving the minimum information problem and its convex dual, and demonstrate their performance on various classiffication tasks. The results show that minimum information classiffiers outperform the corresponding maximum entropy models.

Denaturation of Circular DNA Supercoils and Overtwist ; The denaturation transition of circular DNA is studied within a PolandScheraga type approach, generalized to account for the fact that the total linking number LK, which measures the number of windings of one strand around the other, is conserved. In the model the LK conservation is maintained by invoking both overtwisting and writhing supercoiling mechanisms. This generalizes previous studies which considered each mechanism separately. The phase diagram of the model is analyzed as a function of the temperature and the elastic constant kappa associated with the overtwisting energy for any given loop entropy exponent, c. As is the case where the two mechanisms apply separately, the model exhibits no denaturation transition for c le 2. For c2 and kappa0 we find that the model exhibits a first order transition. The transition becomes of higher order for any kappa0. We also calculate the contribution of the two mechanisms separately in maintaining the conservation of the linking number and find that it is weakly dependent on the loop exponent c.

Radiative typeI seesaw model with dark matter via U1BL gauge symmetry breaking at future linear colliders ; We discuss phenomenology of the radiative seesaw model in which spontaneous breaking of the U1BL gauge symmetry at the TeV scale gives the common origin for masses of neutrinos and dark matter Kanemura et al., 2012. In this model, the stability of dark matter is realized by the global U1DM symmetry which arises by the BL charge assignment. Righthanded neutrinos obtain TeV scale Majorana masses at the tree level. Dirac masses of neutrinos are generated via oneloop diagrams. Consequently, tiny neutrino masses are generated at the twoloop level by the seesaw mechanism. This model gives characteristic predictions, such as light decayable righthanded neutrinos, Dirac fermion dark matter and an extra heavy vector boson. These new particles would be accessible at collider experiments because their masses are at the TeV scale. The U1BL vector boson may be found at the LHC, while the other new particles could only be tested at future linear colliders. We find that the dark matter can be observed at a linear collider with sqrts500 GeV and that light righthanded neutrinos can also be probed with sqrts1 TeV.

Late time behaviors of the expanding universe in the IIB matrix model ; Recently we have studied the Lorentzian version of the IIB matrix model as a nonperturbative formulation of superstring theory. By Monte Carlo simulation, we have shown that the notion of time as well as spaceemerges dynamically from this model, and that we can uniquely extract the realtime dynamics, which turned out to be rather surprising after some critical time, the SO9 rotational symmetry of the ninedimensional space is spontaneously broken down to SO3 and the threedimensional space starts to expand rapidly. In this paper, we study the same model based on the classical equations of motion, which are expected to be valid at later times. After providing a general prescription to solve the equations, we examine a class of solutions, which correspond to manifestly commutative space. In particular, we find a solution with an expanding behavior that naturally solves the cosmological constant problem.

Gaussian Equilibration ; A finite quantum system evolving unitarily equilibrates in a probabilistic fashion. In the general manybody setting the timefluctuations of an observable mathcalA are typically exponentially small in the system size. We consider here quasifree Fermi systems where the Hamiltonian and observables are quadratic in the Fermi operators. We first prove a novel bound on the temporal fluctuations DeltamathcalA2 and then map the equilibration dynamics to a generalized classical XY model in the infinite temperature limit. Using this insight we conjecture that, in most cases, a central limit theorem can be formulated leading to what we call Gaussian equilibration observables display a Gaussian distribution with relative error DeltamathcalAbarmathcalAOL12 where L is the dimension of the single particle space. The conjecture, corroborated by numerical evidence, is proven analytically under mild assumptions for the magnetization in the quantum XY model and for a class of observables in a tightbinding model. We also show that the variance is discontinuous at the transition between a quasifree model and a nonintegrable one.

Offloading in Heterogeneous Networks Modeling, Analysis, and Design Insights ; Pushing data traffic from cellular to WiFi is an example of inter radio access technology RAT offloading. While this clearly alleviates congestion on the overloaded cellular network, the ultimate potential of such offloading and its effect on overall system performance is not well understood. To address this, we develop a general and tractable model that consists of M different RATs, each deploying up to K different tiers of access points APs, where each tier differs in transmit power, path loss exponent, deployment density and bandwidth. Each class of APs is modeled as an independent Poisson point process PPP, with mobile user locations modeled as another independent PPP, all channels further consisting of i.i.d. Rayleigh fading. The distribution of rate over the entire network is then derived for a weighted association strategy, where such weights can be tuned to optimize a particular objective. We show that the optimum fraction of traffic offloaded to maximize SINR coverage is not in general the same as the one that maximizes rate coverage, defined as the fraction of users achieving a given rate.

Space time and the passage of time ; This paper examines the various arguments that have been put forward suggesting either that time does not exist, or that it exists but its flow is not real. I argue that i time both exists and flows; ii an Evolving Block Universe EBU' model of spacetime adequately captures this feature, emphasizing the key differences between the past, present, and future; iii the associated surfaces of constant time are uniquely geometrically and physically determined in any realistic spacetime model based in General Relativity Theory; iv such a model is needed in order to capture the essential aspects of what is happening in circumstances where initial data does not uniquely determine the evolution of spacetime structure because quantum uncertainty plays a key role in that development. Assuming that the functioning of the mind is based in the physical brain, evidence from the way that the mind apprehends the flow of time prefers this evolving time model over those where there is no flow of time.

Entanglement in heterogeneous spin1, frac 12 and homogeneous spin1 systems ; We study the bipartite entanglement of two general classes of heterogeneous spin1,frac 12 and homogeneous spin1 systems. By employing the spin correlation functions, we obtain the reduced twospin density matrix DM and the negativity for these two classes of quantum spin models. We show explicitly that in addition to the one and twopoint correlations, the triad and quad correlations talphabetadeltala SalphaSbetasdeltara and qalphabetadeltagammala Salpha Sbeta sdelta sgammara where alpha, beta, delta, gammapm, z play crucial role in the bipartite entanglement between spins s12. These correlations represent the spin frac 12quadrupole and quadrupolequadrupole correlations, respectively. These correlations do not appear in the spinfrac 12 models. Our results are general and applicable to the different several models of interest with higher reflectional, translational, spinflip and U1 symmetries. The entanglement of many attractive models are investigated.

Charm and Strangeness with HeavyQuark Spin Symmetry ; We study charmed and strange baryon resonances that are generated dynamically within a unitary mesonbaryon coupledchannel model which incorporates heavyquark spin symmetry. This is accomplished by extending the SU3 WeinbergTomozawa chiral Lagrangian to SU8 spinflavor symmetry and implementing a strong flavor symmetry breaking. The model generates dynamically resonances with negative parity in all the isospin, spin, and strange and charm sectors that one can form from an swave interaction between pseudoscalar and vector meson multiplets with 12 and 32 baryons. Our results are compared with experimental data from several facilities as well as with other theoretical models. Moreover, we obtain the properties of charmed pseudoscalar and vector mesons in dense matter within this coupledchannel unitary effective model by taking into account Pauliblocking effects and meson selfenergies in a selfconsistent manner. We obtain the opencharm meson spectral functions in this dense nuclear environment, and discuss their implications on the formation of Dmesic nuclei at FAIR energies.

Beyond inverse Ising model structure of the analytical solution for a class of inverse problems ; I consider the problem of deriving couplings of a statistical model from measured correlations, a task which generalizes the wellknown inverse Ising problem. After reminding that such problem can be mapped on the one of expressing the entropy of a system as a function of its corresponding observables, I show the conditions under which this can be done without resorting to iterative algorithms. I find that inverse problems are local the inverse Fisher information is sparse whenever the corresponding models have a factorized form, and the entropy can be split in a sum of small cluster contributions. I illustrate these ideas through two examples the Ising model on a tree and the onedimensional periodic chain with arbitrary order interaction and support the results with numerical simulations. The extension of these methods to more general scenarios is finally discussed.

QCD modified ghost scalar field dark energy models ; Within the framework of FRW cosmology, we study the QCD modified ghost scalar field models of dark energy in the presence of both interaction and viscosity. For a spatially nonflat FRW universe containing modified ghost dark energy MGDE and dark matter, we obtain the equation of state of MGDE, the deceleration parameter as well as a differential equation governing the MGDE density parameter. We also investigate the growth of structure formation for our model in a linear perturbation regime. Furthermore, we reconstruct both the dynamics and potentials of the quintessence, tachyon, Kessence and dilaton scalar field DE models according to the evolution of the MGDE density.

Onoff Threshold Models of Social Contagion ; We study binary state contagion dynamics on a social network where nodes act in response to the average state of their neighborhood. We model the competing tendencies of imitation and nonconformity by incorporating an offthreshold into standard threshold models of behavior. In this way, we attempt to capture important aspects of fashions and general societal trends. Allowing varying amounts of stochasticity in both the network and node responses, we find different outcomes in the random and deterministic versions of the model. In the limit of a large, dense network, however, we show that these dynamics coincide. The dynamical behavior of the system ranges from steady state to chaotic depending on network connectivity and update synchronicity. We construct a mean field theory for general random networks. In the undirected case, the mean field theory predicts that the dynamics on the network are a smoothed version of the average node response dynamics. We compare our theory to extensive simulations on Poisson random graphs with node responses that average to the chaotic tent map.

Exact solution of two friendly walks above a sticky wall with single and double interactions ; We find, and analyse, the exact solution of two friendly directed walks, modelling polymers, which interact with a wall via contact interactions. We specifically consider two walks that begin and end together so as to imitate a polygon. We examine a general model in which a separate interaction parameter is assigned to configurations where both polymers touch the wall simultaneously, and investigate the effect this parameter has on the integrability of the problem. We find an exact solution of the generating function of the model, and provide a full analysis of the phase diagram that admits three phases with one firstorder and two secondorder transition lines between these phases. We argue that one physically realisable model would see two phase transitions as the temperature is lowered.

Fast Randomized Model Generation for ShapeletBased Time Series Classification ; Time series classification is a field which has drawn much attention over the past decade. A new approach for classification of time series uses classification trees based on shapelets. A shapelet is a subsequence extracted from one of the time series in the dataset. A disadvantage of this approach is the time required for building the shapeletbased classification tree. The search for the best shapelet requires examining all subsequences of all lengths from all time series in the training set. A key goal of this work was to find an evaluation order of the shapelets space which enables fast convergence to an accurate model. The comparative analysis we conducted clearly indicates that a random evaluation order yields the best results. Our empirical analysis of the distribution of highquality shapelets within the shapelets space provides insights into why randomized shapelets sampling is superior to alternative evaluation orders. We present an algorithm for randomized model generation for shapeletbased classification that converges extremely quickly to a model with surprisingly high accuracy after evaluating only an exceedingly small fraction of the shapelets space.

Particle Production at RHIC and LHC Energies ; The production of different particle species is recently measured in PbPb collisions by the ALICE experiment at sqrts7 TeV. This motivates the use of various bosons and baryons measured at lower centerofmass energies in comparing their ratios to the hadron resonance HRG gas model and PYTHIA event generator. It is found that the particletoantiparticle ratios are perfectly reproduce by means of HRG and PYTHIA at RHIC and LHC energies. The kaontopion and protontopion ratios are entirely overestimated by the HRG model. The PYTHIA event generator obviously underestimates the kaontopion ratio and simultaneously reproduces the protontopion ratio, almost perfectly, especially at LHC energy. While mattertoantimatter and nonstrange abundances are partly in line with predictions from the HRG model, it is found in the ALICE experiment that the measured baryon ratios are suppressed by a factor of sim1.5. The strange abundances are overestimated in the HRG model.

Hidden sector dark matter explains the DAMA, CoGeNT, CRESSTII and CDMSSi experiments ; We examine data from the DAMA, CoGeNT, CRESSTII and CDMSSi direct detection experiments in the context of multicomponent hidden sector dark matter. The models considered feature a hidden sector with two or more stable particles charged under an unbroken U1' gauge interaction. The new gauge field can interact with the standard U1Y via renormalizable kinetic mixing, leading to Rutherfordtype elastic scattering of the dark matter particles off ordinary nuclei. We consider the simplest generic model of this type, with a hidden sector composed of two stable particles, F1 and F2. We find that this simple model can simultaneously explain the DAMA, CoGeNT, CRESSTII and CDMSSi data. This explanation has some tension with the most recent results from the XENON100 experiment.

Quadratic hedging schemes for nonGaussian GARCH models ; We propose different schemes for option hedging when asset returns are modeled using a general class of GARCH models. More specifically, we implement local risk minimization and a minimum variance hedge approximation based on an extended Girsanov principle that generalizes Duan's 1995 delta hedge. Since the minimal martingale measure fails to produce a probability measure in this setting, we construct local risk minimization hedging strategies with respect to a pricing kernel. These approaches are investigated in the context of nonGaussian driven models. Furthermore, we analyze these methods for nonGaussian GARCH diffusion limit processes and link them to the corresponding discrete time counterparts. A detailed numerical analysis based on SP 500 European Call options is provided to assess the empirical performance of the proposed schemes. We also test the sensitivity of the hedging strategies with respect to the risk neutral measure used by recomputing some of our results with an exponential affine pricing kernel.

Bianchi typeV dark energy model with varying EoS parameter ; Within the scope of an anisotropic Bianchi typeV cosmological model we have studied the evolution of the universe. The assumption of a diagonal energymomentum tensor leads to some severe restriction on the metric functions, which on its part imposes restriction on the components of the energy momentum tensor. This model allows anisotropic matter distribution. Further using the proportionality condition that relates the shear scalar sigma in the model is proportional to expansion scalar vartheta and the variation law of Hubble parameter, connecting Hubble parameter with volume scale. Exact solution to the corresponding equations are obtained. The EoS parameter for dark energy as well as deceleration parameter is found to be the time varying functions. A qualitative picture of the evolution of the universe corresponding to different of its stages is given using the latest observational data.

Defect stability in phasefield crystal models Stacking faults and partial dislocations ; The primary factors controlling defect stability in phasefield crystal PFC models are examined, with illustrative examples involving several existing variations of the model. Guidelines are presented for constructing models with stable defect structures that maintain high numerical efficiency. The general framework combines both longrange elastic fields and basic features of atomiclevel core structures, with defect dynamics operable over diffusive time scales. Fundamental elements of the resulting defect physics are characterized for the case of fcc crystals. Stacking faults and split Shockley partial dislocations are stabilized for the first time within the PFC formalism, and various properties of associated defect structures are characterized. These include the dissociation width of perfect edge and screw dislocations, the effect of applied stresses on dissociation, Peierls strains for glide, and dynamic contraction of gliding pairs of partials. Our results in general are shown to compare favorably with continuum elastic theories and experimental findings.

Testing for dynamical dark energy models with redshiftspace distortions ; The redshift space distortions in the galaxy power spectrum can be used to measure the growth rate of matter density perturbations deltam. For dynamical dark energy models in General Relativity we provide a convenient analytic formula of fz sigma8z written as a function of the redshift z, where fd ln deltamd ln a a is the cosmological scale factor and sigma8 is the rms amplitude of overdensity at the scale 8 h1 Mpc. Our formula can be applied to the models of imperfect fluids, quintessence, and kessence, provided that the dark energy equation of state w does not vary significantly and that the sound speed is not much smaller than 1. We also place observational constraints on dark energy models of constant w and tracking quintessence from the recent data of redshift space distortions.

Structural properties of Stochastic Abelian Sandpile ; We present some combinatorial results on the stochastic abelian sandpile model. These models are characterized by nondeterministic toppling rules. The recurrence checking for the deterministic case can be performed using the well known burning test which detects presence of forbidden subconfigurations FSC in strongly polynomial time. In the stochastic case, however, even for Manna's model, which is perhaps the simplest nontrivial example, no such procedure is known. In this paper, we address the decision problem of the existence of any FSC in a general stochastic sandpile. We demonstrate a polynomial time algorithm which, given the sandpile graph and toppling rules, decides if there exists an FSC. In the event of a positive answer, it generates at least one FSC for the given sandpile. Repeated application of the algorithm can be used to find many distinct FSCs. We also demonstrate a procedure for creating larger FSCs from smaller ones and use this to create FSCs for the Manna's model. We hope that the structural analysis of stochastic sandpile we perform in this paper, will prove useful in the eventual formulation of a deterministic procedure to decide recurrence.

Interdependent Defense Games Modeling Interdependent Security under Deliberate Attacks ; We propose interdependent defense IDD games, a computational gametheoretic framework to study aspects of the interdependence of risk and security in multiagent systems under deliberate external attacks. Our model builds upon interdependent security IDS games, a model due to Heal and Kunreuther that considers the source of the risk to be the result of a fixed randomizedstrategy. We adapt IDS games to model the attacker's deliberate behavior. We define the attacker's purestrategy space and utility function and derive appropriate cost functions for the defenders. We provide a complete characterization of mixedstrategy Nash equilibria MSNE, and design a simple polynomialtime algorithm for computing all of them, for an important subclass of IDD games. In addition, we propose a randominstance generator of general IDD games based on a version of the realworld Internetderived Autonomous Systems AS graph with around 27K nodes and 100K edges, and present promising empirical results using a simple learning heuristics to compute approximate MSNE in such games.

A fullydiscretestate kinetic theory approach to modeling vehicular traffic ; This paper presents a new mathematical model of vehicular traffic, based on the methods of the generalized kinetic theory, in which the space of microscopic states position and velocity of the vehicles is genuinely discrete. While in the recent literature discretevelocity kinetic models of car traffic have already been successfully proposed, this is, to our knowledge, the first attempt to account for all aspects of the physical granularity of car flow within the formalism of the aforesaid mathematical theory. Thanks to a rich but handy structure, the resulting model allows one to easily implement and simulate various realistic scenarios giving rise to characteristic traffic phenomena of practical interest e.g., queue formation due to roadworks or to a traffic light. Moreover, it is analytically tractable under quite general assumptions, whereby fundamental properties of the solutions can be rigorously proved.

Statefinder Analysis of fT Cosmology ; In this paper, we intend to evaluate and analyze the statefinder parameters in fT cosmology. Friedmann equation in fT model is taken, and the statefinder parameters r,s are calculated. We consider a model of fT which contains a constant, linear and nonlinear form of torsion. We plot r and s in order to characterize this model in the r,s plane. We found that our model fT2C1 sqrtT alpha TC2, predicts the decay of dark energy in the far future while its special case namely teleparallel gravity predicts that dark energy will overcome over all the energy content of the Universe.

Phase Space Dynamics of NonGravitational Interactions between Dark Matter and Dark Energy The Case of Ghost Dark Energy ; We study the phase space asymptotics of the so called Veneziano ghost dark energy models. Models where the ghost field's energy density i rhoghostpropto H, and ii rhoghostpropto HH2, are investigated. Both, cases with and without additional nongravitational interaction between cold dark matter and ghost dark energy, are subject to scrutiny. We pay special attention to the choice of phase space variables leading to bounded and compact phase space so that no critical point of physical interest is missing. A rich asymptotic structure is revealed depending on the kind of nonminimal coupling critical points associated with radiation dominance, matter dominance, cold dark matterghost dark energy scaling, and ghost dark energy dominance, are found. Past and future attractors, as well as saddle equilibrium points, are identified in the corresponding phase spaces.

A uniform model for KirillovReshetikhin crystals. Extended abstract ; We present a uniform construction of tensor products of onecolumn KirillovReshetikhin KR crystals in all untwisted affine types, which uses a generalization of the LakshmibaiSeshadri paths in the theory of the Littelmann path model. This generalization is based on the graph on parabolic cosets of a Weyl group known as the parabolic quantum Bruhat graph. A related model is the socalled quantum alcove model. The proof is based on two lifts of the parabolic quantum Bruhat graph to the Bruhat order on the affine Weyl group and to Littelmann's poset on levelzero weights. Our construction leads to a simple calculation of the energy function. It also implies the equality between a Macdonald polynomial specialized at t0 and the graded character of a tensor product of KR modules.

Model Independent Tests of Cosmic Growth vs Expansion ; We use Gaussian Processes to map the expansion history of the universe in a model independent manner from the Union2.1 supernovae data and then apply these reconstructed results to solve for the growth history. By comparing this to BOSS and WiggleZ large scale structure data we examine whether growth is determined wholly by expansion, with the measured gravitational growth index testing gravity without assuming a model for dark energy. A further model independent analysis looks for redshift dependent deviations of growth from the general relativity solution without assuming the growth index form. Both approaches give results consistent with general relativity.

Short term synaptic depression improves information transfer in perceptual multistability ; Competitive neural networks are often used to model the dynamics of perceptual bistability. Switching between percepts can occur through fluctuations andor a slow adaptive process. Here, we analyze switching statistics in competitive networks with short term synaptic depression and noise. We start by analyzing a ring model that yields spatially structured solutions and complement this with a study of a spacefree network whose populations are coupled with mutual inhibition. Dominance times arising from depression driven switching can be approximated using a separation of timescales in the ring and spacefree model. For purely noisedriven switching, we use energy arguments to justify how dominance times are exponentially related to input strength. We also show that a combination of depression and noise generates realistic distributions of dominance times. Unimodal functions of dominance times are more easily differentiated from one another using Bayesian sampling, suggesting synaptic depression induced switching transfers more information about stimuli than noisedriven switching. Finally, we analyze a competitive network model of perceptual tristability, showing depression generates a memory of previous percepts based on the ordering of percepts.

Modified Rindler acceleration as a nonlinear electromagnetic effect ; The model proposed originally by Mannheim and Kazanas for fitting the shapes of galactic rotation curves has recently been considered by Grumiller to describe gravity of a central object at large distances. Herein we employ the same geometry within the context of nonlinear electrodynamics NED. Pure electrical NED model is shown to generate the novel Rindler acceleration term in the metric which explains anomalous behaviors of test particles satellites. Remarkably a pure magnetic model of NED yields flat rotation curves that may account for the missing dark matter. Weak and Strong Energy conditions are satisfied in such models of NED.

Heavyquark spin symmetry for charmed and strange baryon resonances ; We study charmed and strange baryon resonances that are generated dynamically by a unitary baryonmeson coupledchannels model which incorporates heavyquark spin symmetry. This is accomplished by extending the SU3 WeinbergTomozawa chiral Lagrangian to SU8 spinflavor symmetry plus a suitable symmetry breaking. The model generates resonances with negative parity from the swave interaction of pseudoscalar and vector mesons with 12 and 32 baryons in all the isospin, spin, and strange sectors with one, two, and three charm units. Some of our results can be identified with experimental data from several facilities, such as the CLEO, Belle, or BaBar Collaborations, as well as with other theoretical models, whereas others do not have a straightforward identification and require the compilation of more data and also a refinement of the model.

A generic method to constrain the dark matter model parameters from Fermi observations of dwarf spheroids ; Observation of gammarays from dwarf galaxies is an effective way to search for particle dark matter. Using 4year data of FermiLAT observations on a series of Milky Way satellites, we develop a general way to search for the signals from dark matter annihilation in such objects. Instead of giving prior information about the energy spectrum of dark matter annihilation, we bin the FermiLAT data into several energy bins and build a likelihood map in the energy bin flux plane. The final likelihood of any spectrum can be easily derived through combining the likelihood of all the energy bins. It gives consistent result with that directly calculated using the Fermi Scientific Tool. This method is very efficient for the study of any specific dark matter models with gammarays. We use the new likelihood map with FermiLAT 4 year data to fit the parameter space in three representative dark matter models i toy dark matter model, ii effective dark matter operators, and iii supersymmetric neutralino dark matter.

Conditions and instability in fR gravity with nonminimal coupling between matter and geometry ; In this paper on the basis of the generalized fR gravity model with arbitrary coupling between geometry and matter, four classes of fR gravity models with non minimal coupling between geometry and matter will be studied. By means of conditions of power law expansion and the equation of state of matter less than 13, the relationship among p, w and n, the conditions and the candidate for late time cosmic accelerated expansion will be discussed in the four classes of fR gravity models with non minimal coupling. Furthermore, in order to keep considering models to be realistic ones, the Dolgov Kawasaki instability will be investigated in each of them.

Full 1loop calculation of BRBs,d0to ell bar ell in models beyond the MSSM with SARAH and SPheno ; We present the possibility of calculating the quark flavor changing neutral current decays Bs0to ell bar ell and Bd0to ell bar ell for a large variety of supersymmetric models. For this purpose, the complete oneloop calculation has been implemented in a generic form in the Mathematica package SARAH. This information is used by SARAH to generate Fortran source code for SPheno for a numerical evaluation of these processes in a given model. We comment also on the possibility to use this setup for nonsupersymmetric models.

Discrete Surface Modeling Based on Google Earth A Case Study ; Google Earth GE has become a powerful tool for geological, geophysical and geographical modeling; yet GE can be accepted to acquire elevation data of terrain. In this paper, we present a real study case of building the discrete surface model DSM at HautBarr Castle in France based on the elevation data of terrain points extracted from GE using the COM API. We first locate the position of HautBarr Castle and determine the region of the study area, then extract elevation data of terrain at HautBarr, and thirdly create a planar triangular mesh that covers the study area and finally generate the desired DSM by calculating the elevation of vertices in the planar mesh via interpolating with Universal Kriging UK and Inverse Distance Weighting IDW. The generated DSM can reflect the features of the ground surface at HautBarr well, and can be used for constructingthe Sealed Engineering Geological Model SEGM in further step.

Origin of neutrino masses at the LHC Delta L 2 effective operators and their ultraviolet completions ; Neutrino masses and mixings can be generated in many different ways, with some of these scenarios featuring new physics at energy scales relevant for Large Hadron Collider searches. A systematic approach to constructing a large class of models for Majorana neutrinos may be founded upon a list of gaugeinvariant effective operators formed from quarks, leptons and the Higgs doublet that violate leptonnumber conservation by two units. By opening up these operators in all possible ways consistent with some minimality assumptions, a complete catalogue of a class of minimal radiative neutrino mass models may be produced. In this paper we present an analysis of Feynman diagram topologies relevant for the ultraviolet completions of these effective operators and collect these into a simple recipe that can be used to generate radiative neutrino mass models. Since high massdimension effective operators are suppressed by powers of the scale of new physics, many of the resulting models can be meaningfully tested at the Large Hadron Collider.

Dynamics of the Bianchi I model with nonminimally coupled scalar field near the singularity ; Dynamical systems methods are used to study the evolution of the Bianchi I model with a scalar field. We show that inclusion of the nonminimal coupling term between the scalar field and the curvature changes evolution of the model compared with the minimally coupled case. In the model with the nonminimally coupled scalar field there is a new type of singularity dominated by the nonminimal coupling term. We examine the impact of the nonminimal coupling on the anisotropy evolution and demonstrate the existence of its minimal value in the generic case.

Rotational threshold in global numerical dynamo simulations ; Magnetic field observations of lowmass stars reveal an increase of magnetic activity with increasing rotation rate. The socalled activityrotation relation is usually attributed to changes in the underlying dynamo processes generating the magnetic field. We examine the dependence of the field strength on rotation in global numerical dynamo models and interpret our results on the basis of energy considerations. In agreement with the scaling law proposed by Christensen Aubert 2006, the field strength in our simulations is set by the fraction of the available power used for the magnetic field generation. This is controlled by the dynamo efficiency calculated as the ratio of Ohmic to total dissipation in our models. The dynamo efficiency grows strongly with increasing rotation rate at a Rossby number of 0.1 until it reaches its upper bound of one and becomes independent of rotation. This gain in efficiency is related to the strong rotational dependence of the mean electromotive force in this parameter regime. For multipolar models at Rossby numbers clearly larger than 0.1, on the other hand, we do not find a systematic dependence of the field strength on rotation. Whether the enhancement of the dynamo efficiency found in our dipolar models explains the observed activityrotation relation needs to be further assessed.

Inclusive search for supersymmetry using the razor variables in pp collisions at sqrts 7 TeV ; An inclusive search is presented for new heavy particle pairs produced in sqrts 7 TeV protonproton collisions at the LHC using 4.7 0.1 inverse femtobarns of integrated luminosity. The selected events are analyzed in the 2D razor space of MR, an eventbyevent indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The thirdgeneration sector is probed using the event heavyflavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number of events beyond that predicted by the standard model. Exclusion limits are derived in the CMSSM framework as well as for simplified models. Within the CMSSM parameter space considered, gluino masses up to 800 GeV and squark masses up to 1.35 TeV are excluded at 95 confidence level depending on the model parameters. The direct production of pairs of stop or sbottom quarks is excluded for masses as high as 400 GeV.

Modelling Information Incorporation in Markets, with Application to Detecting and Explaining Events ; We develop a model of how information flows into a market, and derive algorithms for automatically detecting and explaining relevant events. We analyze data from twentytwo political stock markets i.e., betting markets on political outcomes on the Iowa Electronic Market IEM. We prove that, under certain efficiency assumptions, prices in such betting markets will on average approach the correct outcomes over time, and show that IEM data conforms closely to the theory. We present a simple model of a betting market where information is revealed over time, and show a qualitative correspondence between the model and real market data. We also present an algorithm for automatically detecting significant events and generating semantic explanations of their origin. The algorithm operates by discovering significant changes in vocabulary on online news sources using expected entropy loss that align with major price spikes in related betting markets.

Regular models with quadratic equation of state ; We provide new exact solutions to the EinsteinMaxwell system of equations which are physically reasonable. The spacetime is static and spherically symmetric with a charged matter distribution. We utilise an equation of state which is quadratic relating the radial pressure to the energy density. Earlier models, with linear and quadratic equations of state, are shown to be contained in our general class of solutions. The new solutions to the EinsteinMaxwell are found in terms of elementary functions. A physical analysis of the matter and electromagnetic variables indicates that the model is well behaved and regular. In particular there is no singularity in the proper charge density at the stellar centre unlike earlier anisotropic models in the presence of the electromagnetic field.

Modeling complex systems by Generalized Factor Analysis ; We propose a new modeling paradigm for large dimensional aggregates of stochastic systems by Generalized Factor Analysis GFA models. These models describe the data as the sum of a flocking plus an uncorrelated idiosyncratic component. The flocking component describes a sort of collective orderly motion which admits a much simpler mathematical description than the whole ensemble while the idiosyncratic component describes weakly correlated noise. We first discuss static GFA representations and characterize in a rigorous way the properties of the two components. The extraction of the dynamic flocking component is discussed for timestationary linear systems and for a simple classes of separable random fields.

Survival models and health sequences ; Medical investigations focusing on patient survival often generate not only a failure time for each patient but also a sequence of measurements on patient health at annual or semiannual checkups while the patient remains alive. Such a sequence of random length accompanied by a survival time is called a survival process. Ordinarily robust health is associated with longer survival, so the two parts of a survival process cannot be assumed independent. This paper is concerned with a general techniquetime reversalfor constructing statistical models for survival processes. A revival model is a regression model in the sense that it incorporates covariate and treatment effects into both the distribution of survival times and the joint distribution of health outcomes. It also allows individual health outcomes to be used clinically for predicting the subsequent survival time.

Learning New Facts From Knowledge Bases With Neural Tensor Networks and Semantic Word Vectors ; Knowledge bases provide applications with the benefit of easily accessible, systematic relational knowledge but often suffer in practice from their incompleteness and lack of knowledge of new entities and relations. Much work has focused on building or extending them by finding patterns in large unannotated text corpora. In contrast, here we mainly aim to complete a knowledge base by predicting additional true relationships between entities, based on generalizations that can be discerned in the given knowledgebase. We introduce a neural tensor network NTN model which predicts new relationship entries that can be added to the database. This model can be improved by initializing entity representations with word vectors learned in an unsupervised fashion from text, and when doing this, existing relations can even be queried for entities that were not present in the database. Our model generalizes and outperforms existing models for this problem, and can classify unseen relationships in WordNet with an accuracy of 75.8.

Quantum dynamics of evolution of flat universe in the first stage ; Process of formation of the universe with its further expansion in the first evolution stage is investigated in the framework of FriedmannRobertsonWalker metrics on the basis of quantum model, where a new type of matter is introduced, which energy density is dependent on velocity of the expansion. It is shown that such an improvement of the model forms potential barrier for the flat universe at k0 in contrast with generalized Chaplygin gas model. Peculiarities of wave function are analyzed in details, which is calculated by fully quantum nonsemiclassic approach, for the different barrier regions and stages of evolution. Resonant influence of the initial and boundary conditions on the barrier penetrability is shown in contrast with Vilenkin and Hawking approaches. In order to perform a comparative analysis, how much quickly the universe is expanded by different models, new quantum definitions of velocity and Hubble function are introduced. These notions allow us to study dynamics of evolution of universe in quantum cosmology both in the first stage, and in later times.

BoseEinstein condensate dark matter model tested by galactic rotation curves ; Rotation curves of spiral galaxies are fundamental tools in the study of dark matter. Here we test the BoseEinstein condensate BEC dark matter model against rotation curve data of High and Low Surface Brightness HSB and LSB galaxies, respectively. When the rotational velocities increase over the whole observed range, the fit of the BEC model is similar to the one of the NavarroFrenkWhite NFW dark matter model. When however the rotation curves exhibit long flat regions, the NFW profiles provide a slightly better fit.

A CurieWeiss model of selforganized criticality ; We try to design a simple model exhibiting selforganized criticality, which is amenable to a rigorous mathematical analysis. To this end, we modify the generalized Ising CurieWeiss model by implementing an automatic control of the inverse temperature. For a class of symmetric distributions whose density satisfies some integrability conditions, we prove that the sum Sn of the random variables behaves as in the typical critical generalized Ising CurieWeiss model. The fluctuations are of order n34, and the limiting law is Cexplambda x4,dx where C and lambda are suitable positive constants.

Coevolution of networks and quantum dynamics a generalization of preferential attachment ; We propose a model of network growth in which the network is coevolving together with the dynamics of a quantum mechanical system, namely a quantum walk taking place over the network. The model naturally generalizes the Barab'asiAlbert model of preferential attachment and has a rich set of tunable parameters, such as the initial conditions of the dynamics or the interaction of the system with its environment. We show that the model produces networks with twomodal powerlaw degree distributions, superhubs, finite clustering coefficient, smallworld behaviour and nontrivial degreedegree correlations.

Analytically solvable model of an electronic MachZehnder interferometer ; We consider a class of models of nonequilibrium electronic MachZehnder interferometers built on integer quantum Hall edges states. The models are characterized by the electronelectron interaction being restricted to the inner part of the interferometer and transmission coefficients of the quantum quantum point contacts, defining the interferometer, which may take arbitrary values from zero to one. We establish an exact solution of these models in terms of singleparticle quantities determinants and resolvents of Fredholm integral operators. In the general situation, the results can be obtained numerically. In the case of strong charging interaction, the operators acquire the block Toeplitz form. Analyzing the corresponding RiemannHilbert problem, we reduce the result to certain singular singlechannel determinants which are a generalization of Toeplitz determinants with FisherHartwig singularities, and obtain an analytic result for the interference current and, in particular, for the visibility of AharonovBohm oscillations. Our results, which are in good agreement with experimental observations, show an intimate connection between the observed lobe structure in the visibility of AharonovBohm oscillations and multiple branches in the asymptotics of singular integral determinants.

Dualities in population genetics a fresh look with new dualities ; We apply our general method of duality, introduced in Giardina', Kurchan, Redig, J. Math. Phys. 48, 033301 2007, to models of population dynamics. The classical dualities between forward and ancestral processes can be viewed as a change of representation in the classical creation and annihilation operators, both for diffusions dual to coalescents of Kingman's type, as well as for models with finite population size. Next, using SU1,1 raising and lowering operators, we find new dualities between the WrightFisher diffusion with d types and the Moran model, both in presence and absence of mutations. These new dualities relates two forward evolutions. From our general scheme we also identify selfduality of the Moran model.

Robust NearSeparable Nonnegative Matrix Factorization Using Linear Optimization ; Nonnegative matrix factorization NMF has been shown recently to be tractable under the separability assumption, under which all the columns of the input data matrix belong to the convex cone generated by only a few of these columns. Bittorf, Recht, R'e and Tropp Factoring nonnegative matrices with linear programs', NIPS 2012 proposed a linear programming LP model, referred to as Hottopixx, which is robust under any small perturbation of the input matrix. However, Hottopixx has two important drawbacks i the input matrix has to be normalized, and ii the factorization rank has to be known in advance. In this paper, we generalize Hottopixx in order to resolve these two drawbacks, that is, we propose a new LP model which does not require normalization and detects the factorization rank automatically. Moreover, the new LP model is more flexible, significantly more tolerant to noise, and can easily be adapted to handle outliers and other noise models. Finally, we show on several synthetic datasets that it outperforms Hottopixx while competing favorably with two stateoftheart methods.

Hermitian versus nonHermitian representations for minimal length uncertainty relations ; We investigate four different types of representations of deformed canonical variables leading to generalized versions of Heisenberg's uncertainty relations resulting from noncommutative spacetime structures. We demonstrate explicitly how the representations are related to each other and study three characteristically different solvable models on these spaces, the harmonic oscillator, the manifestly nonHermitian Swanson model and an intrinsically noncommutative model with PoeschlTeller type potential. We provide an analytical expression for the metric in terms of quantities specific to the generic solution procedure and show that when it is appropriately implemented expectation values are independent of the particular representation. A recently proposed inequivalent representation resulting from Jordan twists is shown to lead to unphysical models. We suggest an antiPTsymmetric modification to overcome this shortcoming.

Is EddingtonBornInfeld theory really free of cosmological singularities ; The EddingtoninspiredBornInfeld EiBI theory has been recently resurrected. Such a theory is characterized by being equivalent to Einstein theory in vacuum but differing from it in the presence of matter. One of the virtues of the theory is to avoid the Big Bang singularity for a radiation filled universe. In this paper, we analyze singularity avoidance in this kind of model. More precisely, we analyze the behavior of a homogeneous and isotropic universe filled with phantom energy in addition to the dark and baryonic matter. Unlike the Big Bang singularity that can be avoided in this kind of model through a bounce or a loitering effect on the physical metric, we find that the Big Rip singularity is unavoidable in the EiBI phantom model even though it can be postponed towards a slightly further future cosmic time as compared with the same singularity in other models based on the standard general relativity and with the same matter content described above.

Longitudinal analysis of gene expression profiles using functional mixedeffects models ; In many longitudinal microarray studies, the gene expression levels in a random sample are observed repeatedly over time under two or more conditions. The resulting time courses are generally very short, highdimensional, and may have missing values. Moreover, for every gene, a certain amount of variability in the temporal profiles, among biological replicates, is generally observed. We propose a functional mixedeffects model for estimating the temporal pattern of each gene, which is assumed to be a smooth function. A statistical test based on the distance between the fitted curves is then carried out to detect differential expression. A simulation procedure for assessing the statistical power of our model is also suggested. We evaluate the model performance using both simulations and a real data set investigating the human host response to BCG exposure.

On asymptotically optimal confidence regions and tests for highdimensional models ; We propose a general method for constructing confidence intervals and statistical tests for single or lowdimensional components of a large parameter vector in a highdimensional model. It can be easily adjusted for multiplicity taking dependence among tests into account. For linear models, our method is essentially the same as in Zhang and Zhang J. R. Stat. Soc. Ser. B Stat. Methodol. 76 2014 217242 we analyze its asymptotic properties and establish its asymptotic optimality in terms of semiparametric efficiency. Our method naturally extends to generalized linear models with convex loss functions. We develop the corresponding theory which includes a careful analysis for Gaussian, subGaussian and bounded correlated designs.

Intrinsic energy of LemaitreTolmanBondi models and cosmological implications ; Recently, some LemaitreTolmanBondi metrics have been considered as models alternative to the dark energy within the FriedmannLemaitreRobertsonWalker universes. The vanishing of the intrinsic energy of these metrics is examined since such a vanishing, in the present case and in general, could be interpreted as a necessary condition to consider the possibility of the quantum creation of a metric. More specifically, this vanishing is examined in the particular case where the LemaitreTolmanBondi metrics behave asymptotically like a FriedmannLemaitreRobertsonWalker universe. Finally, we deal with a particular model ruled out after being confronted with cosmic observations. In a minimal agreement with this negative result, leaving aside an unstable case, the value of the intrinsic energy of this particular model does not vanish and becomes in fact minus infinite.

Baryon Asymmetry and Dark Matter Through the VectorLike Portal ; A possible connection between the cosmological baryon asymmetry, dark matter and vectorlike fermions is investigated. In this scenario an asymmetry generated through baryogenesis or leptogenesis in the vectorlike matter sector connects the baryon asymmetry to the dark matter density. We present explicit renormalizable models where this connection occurs. These models have asymmetric dark matter and a significant invisible Higgs decay width to dark matter particles is possible. We refer to this type of scenario as the vectorlike portal. In some asymmetric dark matter models there are potential naturalness issues for the low energy effective theory. We address that issue in the models we consider by starting with a Lagrangian that is the most general renormalizable one consistent with the gauge and discrete symmetries and showing the low energy effective theory automatically has the required form as a consequence of the symmetries of the full theory. We show that the mass of the dark matter candidate is predicted in these scenarios.

Topological phase transition in a generalized KaneMeleHubbard model A combined Quantum Monte Carlo and Green's function study ; We study a generalized KaneMeleHubbard model with thirdneighbor hopping, an interacting twodimensional model with a topological phase transition as a function of thirdneighbor hopping, by means of the determinant projector Quantum Monte Carlo QMC method. This technique is essentially numerically exact on models without a fermion sign problem, such as the one we consider. We determine the interactiondependence of the Z2 topological insulatortrivial insulator phase boundary by calculating the Z2 invariants directly from the singleparticle Green's function. The interactions push the phase boundary to larger values of thirdneighbor hopping, thus stabilizing the topological phase. The observation of boundary shifting entirely stems from quantum deguctuations. We also identify qualitative features of the singleparticle Green's function which are computationally useful in numerical searches for topological phase transitions without the need to compute the full topological invariant.

Predictions in multifield models of inflation ; This paper presents a method for obtaining an analytic expression for the density function of observables in multifield models of inflation with sumseparable potentials. The most striking result is that the density function in general possesses a sharp peak and the location of this peak is only mildly sensitive to the distribution of initial conditions. A simple argument is given for why this result holds for a more general class of models than just those with sumseparable potentials and why for such models, it is possible to obtain robust predictions for observable quantities. As an example, the joint density function of the spectral index and running in double quadratic inflation is computed. For scales leaving the horizon 55 efolds before the end of inflation, the density function peaks at ns0.967 and alpha0.0006 for the spectral index and running respectively.

Visualization of the Godel universe ; The standard model of modern cosmology, which is based on the FriedmannLemaitreRobertsonWalker metric, allows the definition of an absolute time. However, there exist cosmological models consistent with the theory of general relativity for which such a definition cannot be given since they offer the possibility of time travel. The simplest of these models is the cosmological solution discovered by Kurt Godel, which describes a homogeneous, rotating universe. Disregarding the paradoxes that come along with the abolishment of causality in such spacetimes, we are interested in the purely academical question how an observer would visually perceive the time travel of an object in Godel's universe. For this purpose, we employ the technique of ray tracing, a standard tool in computer graphics, and visualize various scenarios to bring out the optical effects experienced by an observer located in this universe. In this way, we provide a new perspective on the spacetime structure of Godel's model.

Novel discrete symmetries in the general N 2 supersymmetric quantum mechanical model ; In addition to the usual supersymmetric SUSY continuous symmetry transformations for the general N 2 SUSY quantum mechanical model, we show the existence of a set of novel discrete symmetry transformations for the Lagrangian of the above SUSY quantum mechanical model. Out of all these discrete symmetry transformations, a unique discrete transformation corresponds to the Hodge duality operation of differential geometry and the above SUSY continuous symmetry transformations and their anticommutator provide the physical realizations of the de Rham cohomological operators of differential geometry. Thus, we provide a concrete proof of our earlier conjecture that any arbitrary N 2 SUSY quantum mechanical model is an example of a Hodge theory where the cohomological operators find their physical realizations in the language of symmetry transformations of this theory. Possible physical implications of our present study are pointed out, too.

Reliability and efficiency of generalized rumor spreading model on complex social networks ; We introduce the generalized rumor spreading model and investigate some properties of this model on different complex social networks. Despite pervious rumor models that both the spreaderspreader SS and the spreaderstifler SR interactions have the same rate alpha, we define alpha1 and alpha2 for SS and SR interactions, respectively. The effect of variation of alpha1 and alpha2 on the final density of stiflers is investigated. Furthermore, the influence of the topological structure of the network in rumor spreading is studied by analyzing the behavior of several global parameters such as reliability and efficiency. Our results show that while networks with homogeneous connectivity patterns reach a higher reliability, scalefree topologies need a less time to reach a steady state with respect the rumor.

ABC Reinforcement Learning ; This paper introduces a simple, general framework for likelihoodfree Bayesian reinforcement learning, through Approximate Bayesian Computation ABC. The main advantage is that we only require a prior distribution on a class of simulators generative models. This is useful in domains where an analytical probabilistic model of the underlying process is too complex to formulate, but where detailed simulation models are available. ABCRL allows the use of any Bayesian reinforcement learning technique, even in this case. In addition, it can be seen as an extension of rollout algorithms to the case where we do not know what the correct model to draw rollouts from is. We experimentally demonstrate the potential of this approach in a comparison with LSPI. Finally, we introduce a theorem showing that ABC is a sound methodology in principle, even when nonsufficient statistics are used.

Noncommutative gauge theories on mathbbR2 as matrix models ; We study a class of noncommutative gauge theory models on 2dimensional Moyal space from the viewpoint of matrix models and explore some related properties. Expanding the action around symmetric vacua generates non local matrix models with polynomial interaction terms. For a particular vacuum, we can invert the kinetic operator which is related to a Jacobi operator. The resulting propagator can be expressed in terms of Chebyschev polynomials of second kind. We show that non vanishing correlations exist at large separations. General considerations on the kinetic operators stemming from the other class of symmetric vacua, indicates that only one class of symmetric vacua should lead to fast decaying propagators. The quantum stability of the vacuum is briefly discussed.

Agentbased modeling of a price information trading business ; We describe an agentbased simulation of a fictional but feasible information trading business. The Gas Price Information Trader GPIT buys information about realtime gas prices in a metropolitan area from drivers and resells the information to drivers who need to refuel their vehicles. Our simulation uses real world geographic data, lifestyledependent driving patterns and vehicle models to create an agentbased model of the drivers. We use real world statistics of gas price fluctuation to create scenarios of temporal and spatial distribution of gas prices. The price of the information is determined on a casebycase basis through a simple negotiation model. The trader and the customers are adapting their negotiation strategies based on their historical profits. We are interested in the general properties of the emerging information market the amount of realizable profit and its distribution between the trader and customers, the business strategies necessary to keep the market operational such as promotional deals, the price elasticity of demand and the impact of pricing strategies on the profit.