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Continuous-wave mirrorless lasing at 2.21 μm in sodium vaporsAug 31 2018We demonstrate backward-directed continuous-wave (cw) emission at 2.21 {\mu}m generated on the 4P3/2-4S1/2 population-inverted transition in Na vapors two-photon excited with resonant laser light at 589 and 569 nm. Our study of power and atom-number-density ... More

Remote sensing of geomagnetic fields and atomic collisions in the mesosphereFeb 09 2018Magnetic-field sensing has contributed to the formulation of the plate-tectonics theory, the discovery and mapping of underground structures on Earth, and the study of magnetism in other planets. Filling the gap between space-based and near-Earth observation, ... More

Twisted Pseudo-differential Operators on Type I Locally Compact GroupsMay 16 2016Let $\G$ be a locally compact group satisfying some technical requirements and $\wG$ its unitary dual. Using the theory of twisted crossed product $C^*$-algebras, we develop a twisted global quantization for symbols defined on $\G\times\wG$ and taking ... More

Cayley-type graphs for group-subgroup pairsJun 12 2014Nov 24 2014In this paper we introduce a Cayley-type graph for group-subgroup pairs and present some elementary properties of such graphs, including connectedness, their degree and partition structure, and vertex-transitivity. We relate these properties to those ... More

The Proper Motion of the Large Magellanic Cloud: A ReanalysisJan 10 2006We have determined the proper motion (PM) of the Large Magellanic Cloud (LMC) relative to four background quasi-stellar objects, combining data from two previous studies made by our group, and new observations carried out in four epochs not included the ... More

The Large-Scale 3-point correlation function of SDSS Luminous Red GalaxiesNov 19 2010We present new measurements of the redshift-space three-point correlation function (3PCF) of Luminous Red Galaxies (LRGs) from the Sloan Digital Sky Survey (SDSS). Using the largest dataset to date, the Data Release 7 (DR7) LRGs, and an improved binning ... More

Integrable Abelian Vortex-like solitonsDec 06 2016We propose a modified version of the Ginzburg-Landau energy functional admitting static solitons and determine all the Painlev\'e-integrable cases of its Bogomolny equations of a given class of models. Explicit solutions are determined in terms of the ... More

On the constancy regions for mixed test idealsAug 25 2012Dec 04 2012In this note we study the partition of $\mathbb{R}_{\geq0}^{n}$ given by the regions where the mixed test ideals $\tau(\mathfrak{a}_{1}^{t_{1}}... \mathfrak{a}_{n}^{t_{n}})$ are constant. We show that each region can be described as the preimage of a ... More

Orthogonal Polynomials and Sharp Estimates for the Schrödinger EquationFeb 21 2017Aug 24 2017In this paper we study sharp estimates for the Schr\"odinger operator via the framework of orthogonal polynomials. We use spherical harmonics and Gegenbauer polynomials to prove a new weighted inequality for the Schr\"odinger equation that is maximized ... More

H - T phase diagram of YbCo2Si2 with H // [100]Oct 30 2009May 23 2011We report on the first high-resolution dc-magnetisation ($M$) measurements on a single crystal of \ycs. $M$ was measured down to 0.05 K and in fields up to 12 T, with the magnetic field $H$ parallel to the crystallographic direction [100]. Two antiferromagnetic ... More

Proper motions of Local Group dwarf spheroidal galaxies I: First ground-based results for FornaxMay 26 2010In this paper we present in detail the methodology and the first results of a ground-based program to determine the absolute proper motion of the Fornax dwarf spheroidal galaxy. The proper motion was determined using bona-fide Fornax star members measured ... More

Twistorial constructions of spacelike surfaces in Lorentzian 4-manifoldsFeb 17 1999We investigate the twistor space and the Grassmannian fibre bundle of a Lorentzian 4-space with natural almost optical structures and its induced CR-structures. The twistor spaces of the Lorentzian space forms $\R^4_1, \Di{S}^4_1$ and $\Di{H}^4_1$ are ... More

Genoogle: an indexed and parallelized search engine for similar DNA sequencesJul 10 2015The search for similar genetic sequences is one of the main bioinformatics tasks. The genetic sequences data banks are growing exponentially and the searching techniques that use linear time are not capable to do the search in the required time anymore. ... More

A Central Limit Theorem for OperatorsOct 28 2015Nov 28 2015We prove an analogue of the Central Limit Theorem for operators. For every operator $K$ defined on $\mathbb{C}[x]$ we construct a sequence of operators $K_N$ defined on $\mathbb{C}[x_1,...,x_N]$ and demonstrate that, under certain orthogonality conditions, ... More

Minimality of one invariant lamination for partially hyperbolic attractorsApr 22 2014We prove that at least one of the two invariant laminations of a strongly partially hyperbolic attractor with one-dimensional center bundle is minimal. This result extends those in [7] about minimal foliations for robustly transitive diffeomorphisms.

Improving Sparsity in Kernel Adaptive Filters Using a Unit-Norm DictionaryJul 13 2017Kernel adaptive filters, a class of adaptive nonlinear time-series models, are known by their ability to learn expressive autoregressive patterns from sequential data. However, for trivial monotonic signals, they struggle to perform accurate predictions ... More

Three-dimensional numerical simulations of fast-to-Alfven conversion in sunspotsAug 28 2012The conversion of fast waves to the Alfven mode in a realistic sunspot atmosphere is studied through three-dimensional numerical simulations. An upward propagating fast acoustic wave is excited in the high-beta region of the model. The new wave modes ... More

A remark on conformal $\SU(p,q)$-holonomyApr 18 2006If the conformal holonomy group $Hol(\mathcal{T})$ of a simply connected space with conformal structure of signature $(2p-1,2q-1)$ is reduced to $\U(p,q)$ then the conformal holonomy is already contained in the special unitary group $\SU(p,q)$. We present ... More

Counterexamples to Ruelle's inequality in the noncompact caseOct 16 2015In this paper we show that there exists a large family of smooth dynamical systems defined over noncompact spaces that does not satisfy Ruelle's inequality between entropy and Lyapunov exponents.

A Sharpened Strichartz Inequality For Radial FunctionsSep 23 2017Jul 25 2018We prove a sharpened version of the Strichartz inequality for radial solutions of the Schr\"odinger equation in $\mathbb{R}^2\times \mathbb{R}$. We establish an improved upper bound for functions that nearly extremize the inequality, with a negative second ... More

Conformal holonomy of bi-invariant metricsJun 15 2004We discuss in this paper the conformal geometry of bi-invariant metrics on compact semisimple Lie groups. For this purpose we develop a conformal Cartan calculus adapted to this problem. In particular, we derive an explicit formula for the holonomy algebra ... More

A decomposition for the Schrodinger equation with applications to bilinear and multilinear estimatesJul 27 2015A new decomposition for frequency-localized solutions to the Schrodinger equation is given which describes the evolution of the wavefunction using a weighted sum of Lipschitz tubes. As an application of this decomposition, we provide a new proof of the ... More

C*-algebras associated with endomorphisms of groupsAug 06 2013Aug 07 2013In this work we construct a C*-algebra from an injective endomorphisms of some group G, allowing the endomorphism to have infinite cokernel. We generalize results obtained by I. Hirshberg and also by J. Cuntz and A. Vershik. In good cases we show that ... More

Computing Tropical Linear SpacesSep 19 2011May 02 2012We define and study the cyclic Bergman fan of a matroid M, which is a simplicial polyhedral fan supported on the tropical linear space T(M) of M and is amenable to computational purposes. It slightly refines the nested set structure on T(M), and its rays ... More

Partially Hyperbolic Sets with a Dynamically Minimal Invariant LaminationMar 21 2017We study partially hyperbolic sets of C1-diffeomorphisms. For these sets there are defined the strong stable and strong unstable laminations. A lamination is called dynamically minimal when the orbit of each leaf intersects the set densely. We prove that ... More

Holography of negative energy statesSep 13 2018Jan 07 2019Quantum states with negative energy densities have been long known to exist in quantum field theories. We explore the structure of such states for holographic theories using quantum information theory tools and show how certain negative energy states ... More

Dissipative charging of a quantum batteryFeb 01 2019We show that a cyclic unitary process can extract work from the thermodynamic equilibrium state of an engineered quantum dissipative process. Systems in the equilibrium states of these processes serve as batteries, storing energy. The dissipative process ... More

Large gaps imputation in remote sensed imagery of the environmentJun 22 2010Imputation of missing data in large regions of satellite imagery is necessary when the acquired image has been damaged by shadows due to clouds, or information gaps produced by sensor failure. The general approach for imputation of missing data, that ... More

Magnetic phase diagram of YbCo2Si2 derived from magnetization measurementsNov 12 2011Dec 20 2011We report on high-resolution dc-magnetization (M) measurements on a high-quality single crystal of YbCo2Si2. M was measured down to 0.05K and in fields up to 4T, with the magnetic field oriented along the crystallographic directions [100], [110] and [001] ... More

Basic parameters of three star clusters in the Small Magellanic Cloud: Kron 11, Kron 63 and NGC 121Aug 26 2008We present observations for three star clusters, Kron 11, Kron 63 and NGC 121, in the Small Magellanic Cloud. We have studied their structure and derived their fundamental parameters by means of their luminosity functions, their color magnitude diagrams ... More

Ruelle's inequality and Pesin's entropy formula for the geodesic flow on negatively curved noncompact manifoldsJan 12 2016Jun 15 2016In this paper we study different notions of entropy of measure-preserving dynamical systems defined on noncompact spaces. We see that some classical results for compact spaces remain partially valid in this setting. We define a new kind of entropy for ... More

The Standard Candle Method for Type II-Plateau SupernovaeOct 30 2008In this thesis we study the "standardized candle method" using a sample of 37 nearby (redshift < 0.06) Type II-plateau supernovae with BVRI photometry and optical spectroscopy. An analytic procedure is implemented to fit light, color, and velocity curves. ... More

Normal Conformal Killing FormsJun 16 2004We introduce in this paper normal twistor equations for differential forms and study their solutions, the so-called normal conformal Killing forms. The twistor equations arise naturally from the canonical normal Cartan connection of conformal geometry. ... More

About Twistor Spinors with Zero in Lorentzian GeometryJun 15 2004Jul 28 2009We describe the local conformal geometry of a Lorentzian spin manifold $(M,g)$ admitting a twistor spinor $\phi$ with zero. Moreover, we describe the shape of the zero set of $\phi$. If $\phi$ has isolated zeros then the metric $g$ is locally conformally ... More

Universal C*-algebras of endomorphisms of groups and partial actionsJun 08 2017Jul 09 2017We present a different way to study the C*-algebra associated with an injective endomorphism of a group G of infinite cokernel. We follow the work of Boava and Exel to construct a partial crossed product representation of that C*-algebra and show properties ... More

Ruelle's inequality in negative curvatureJan 12 2016Jan 16 2018In this paper we study different notions of entropy for measure-preserving dynamical systems defined on noncompact spaces. We see that some classical results for compact spaces remain partially valid in this setting. We define a new kind of entropy for ... More

Local tropical linear spacesNov 22 2012Jun 16 2013In this paper we study general tropical linear spaces locally: For any basis B of the matroid underlying a tropical linear space L, we define the local tropical linear space L_B to be the subcomplex of L consisting of all vectors v that make B a basis ... More

Transient Anomaly Imaging in Visco-Elastic Media Obeying a Frequency Power-LawMay 31 2010In this work, we consider the problem of reconstructing a small anomaly in a viscoelastic medium from wave-field measurements. We choose Szabo's model to describe the viscoelastic properties of the medium. Expressing the ideal elastic field without any ... More

Determinant expressions of constraint polynomials and the spectrum of the asymmetric quantum Rabi modelDec 12 2017Dec 05 2018The purpose of this paper is to study the exceptional eigenvalues of the asymmetric quantum Rabi models (AQRM), specifically, to determine the degeneracy of their eigenstates. Here, the Hamiltonian $H^{\epsilon}_{\text{Rabi}}$ of the AQRM is defined by ... More

String Dual of N=1 Super Yang-Mills on the CylinderApr 30 2008We study the stringy description of N=1 supersymmetric SU(N) gauge theory on R^{1,2}xS^1. Our description is based on the known Maldacena-Nunez solution, properly modified to account for the compact dimension. The most interesting of its properties is ... More

On pseudo-Hermitian Einstein spacesFeb 14 2005We describe and construct here pseudo-Hermitian structures $\theta$ without torsion (i.e. with transversal symmetry) whose Webster-Ricci curvature tensor is a constant multiple of the exterior differential $d\theta$. We call these structures pseudo-Hermitian ... More

A Note on Band-limited Minorants of an Euclidean BallApr 04 2017Dec 08 2017We study the Beurling-Selberg problem of finding band-limited $L^1$-functions that lie below the indicator function of an Euclidean ball. We compute the critical radius of the support of the Fourier transform for which such construction can have a positive ... More

Integrable Abelian Vortex-like solitonsDec 06 2016Feb 26 2017We propose a modified version of the Ginzburg-Landau energy functional admitting static solitons and determine all the Painlev\'e-integrable cases of its Bogomolny equations of a given class of models. Explicit solutions are determined in terms of the ... More

Interpolation Formulas With Derivatives in De Branges SpacesMar 17 2015The purpose of this paper is to prove an interpolation formula involving derivatives for entire functions of exponential type. We extend the interpolation formula derived by J. Vaaler in [37, Theorem 9] to general $L^p$ de Branges spaces. We extensively ... More

Some remarks on non-symmetric polarizationJun 08 2018Let $P:\mathbb{C}^n\rightarrow \mathbb{C}$ be an $m$-homogeneous polynomial given by \[P(x)= \sum_{1\leq j_1\leq \ldots \leq j_m \leq n} c_{j_1 \ldots j_m} x_{j_1}\ldots x_{j_m}.\] Defant and Schl\"uters defined a non-symmetric associated $m$-form $L_P: ... More

Holographic heat engines and static black holes: a general efficiency formulaJan 23 2018Feb 04 2018Starting from simple observations regarding heat flows for static black holes (or any thermodynamic system with $C_V=0$), we get inequalities which restrict their change in energy and adiabatic curves in the $p-T$ plane. From these observations we then ... More

C*-algebras of endomorphisms of groups with finite cokernel and partial actionsJul 10 2017In this paper we extend the constructions of Boava and Exel to present the C*-algebra associated with an injective endomorphism of a group with finite cokernel as a partial group algebra and consequently as a partial crossed product. With this representation ... More

Properties of a Hilbertian Norm for PerimeterSep 24 2017Oct 10 2017A recent paper of Jerison and Figalli proved a relationship between the $H^{1/2}$ norms of smoothed out indicator functions of sets and their perimeter. We continue this line of investigation and extend it in two ways. First, we describe a description ... More

Ferromagnetic Quantum Criticality in the Quasi-One-Dimensional Heavy Fermion Metal YbNi4P2Aug 22 2011We present a new Kondo-lattice system, YbNi4P2, which is a clean heavy-fermion metal with a severely reduced ferromagnetic ordering temperature at T_C=0.17K, evidenced by distinct anomalies in susceptibility, specific-heat, and resistivity measurements. ... More

Smoothed Analysis of Moore-Penrose InversionFeb 25 2010Apr 30 2010We perform a smoothed analysis of the condition number of rectangular matrices. We prove that, asymptotically, the expected value of this condition number depends only of the elongation of the matrix, and not on the center and variance of the underlying ... More

Constructive proof of extended Kapranov theoremOct 27 2008Kapranov Theorem is a well known generalization of Newton-Puiseux theorem for the case of several variables. This theorem is stated mainly in the context of tropical geometry. We present a new, constructive proof, that also characterizes the possible ... More

Tropical Plane Geometric Constructions: a Transfer Technique in Tropical GeometryNov 29 2005Oct 10 2007The notion of geometric construction is introduced. This notion allows to compare incidence configurations in the algebraic and tropical plane. We provide an algorithm such that, given a tropical instance of a geometric construction, it computes sufficient ... More

On the Chern-Simons topological term at finite temperatureSep 10 1997Sep 11 1997The parity-violating topological term in the effective action for 2+1 massive fermions is computed at finite temperature in the presence of a constant background field strength tensor. Gauge invariance of the finite-temperature effective action is also ... More

Transport and dynamics on open quantum graphsJul 13 2001We study the classical limit of quantum mechanics on graphs by introducing a Wigner function for graphs. The classical dynamics is compared to the quantum dynamics obtained from the propagator. In particular we consider extended open graphs whose classical ... More

Torsion points on y^2=x^6+1Oct 20 1997Let C be the curve y^2=x^6+1 of genus 2 over a field of characteristic zero. Consider C embedded in its Jacobian J by sending one of the points at infinity on C to the origin of J. In this brief note we show that the points of C whose image on J are torsion ... More

Componentwise condition numbers of random sparse matricesJul 07 2008Jul 08 2008We prove an O(log n) bound for the expected value of the logarithm of the componentwise (and, a fortiori, the mixed) condition number of a random sparse n x n matrix. As a consequence, small bounds on the average loss of accuracy for triangular linear ... More

Partial Crossed Product of a group G vs Crossed Product of S(G)May 23 2008In this work we present a new definition to the Partial Crossed Product by actions of inverse semigroups in a C^*-algebra, without using the covariant representations as Sieben did in [5]. Also we present an isomorphism between the partial crossed products ... More

Tropical IdealsSep 13 2016We introduce and study a special class of ideals, called tropical ideals, in the semiring of tropical polynomials, with the goal of developing a useful and solid algebraic foundation for tropical geometry. The class of tropical ideals strictly includes ... More

Fluctuations of the Longest Common Subsequence for Sequences of Independent BlocksJan 08 2010Nov 12 2010The problem of the fluctuation of the Longest Common Subsequence (LCS) of two i.i.d. sequences of length $n>0$ has been open for decades. There exist contradicting conjectures on the topic. Chvatal and Sankoff conjectured in 1975 that asymptotically the ... More

Control and Stabilization of the Benjamin-Ono Equation on a Periodic DomainSep 22 2012It was proved by Linares and Ortega that the linearized Benjamin-Ono equation posed on a periodic domain T with a distributed control supported on an arbitrary subdomain is exactly controllable and exponentially stabilizable. The aim of this paper is ... More

Smoothed analysis of componentwise condition numbers for sparse matricesFeb 25 2013We perform a smoothed analysis of the componentwise condition numbers for determinant computation, matrix inversion, and linear equations solving for sparse n times n matrices. The bounds we obtain for the ex- pectations of the logarithm of these condition ... More

Nonequilibrium mesoscopic Fermi reservoirs distributions and particle current through a coherent quantum systemFeb 01 2013We study particle current and occupation distribution in a recently proposed model for coherent quantum transport. In this model a system connected to mesoscopic Fermi reservoirs (mesoreservoir) is driven out of equilibrium by the action of superreservoirs ... More

Higher cohomology for Anosov actions on certain homogeneous spacesJul 23 2011Aug 24 2012We study the smooth untwisted cohomology with real coefficients for the action on [SL(2, R) \times \cdot \cdot \cdot \times SL(2, R)]/{\Gamma} by the subgroup of diagonal matrices, where {\Gamma} is an irreducible lattice. In the top degree, we show that ... More

Computing Hypercircles by Moving HyperplanesJun 07 2011Let K be a field of characteristic zero, alpha algebraic of degree n over K. Given a proper parametrization psi of a rational curve C, we present a new algorithm to compute the hypercircle associated to the parametrization psi. As a consequence, we can ... More

Parque Astronómico de Atacama: An ideal site for millimeter, submillimeter, and mid-infrared astronomyOct 09 2014Mar 30 2015The area of Chajnantor, at more than 5000 meters altitude in northern Chile, offers unique atmospheric and operational conditions which arguably make it the best site in the world for millimeter, submillimeter, and mid-infrared observatories. Long-term ... More

First integrals of affine connections and Hamiltonian systems of hydrodynamic typeOct 07 2015Aug 26 2016We find necessary and sufficient conditions for a local geodesic flow of an affine connection on a surface to admit a linear first integral. The conditions are expressed in terms of two scalar invariants of differential orders 3 and 4 in the connection. ... More

About a new family of sequencesJul 20 2016First we define a new kind of function over $\mathbb{N}$. For each $i\in\mathbb{N}$ we have an associated function, which will be called $S_i$ . Then we define a new kind of sequence, to be made from the functions $S_i$ . Finally, we will see that some ... More

Metrisability of Painlevé equationsApr 12 2016Feb 05 2018We solve the metrisability problem for the six Painlev\'e equations, and more generally for all 2nd order ODEs with Painlev\'e property, and determine for which of these equations their integral curves are geodesics of a (pseudo) Riemannian metric on ... More

A stable, polynomial-time algorithm for the eigenpair problemOct 01 2014We describe algorithms for computing eigenpairs (eigenvalue--eigenvector) of a complex $n\times n$ matrix $A$. These algorithms are numerically stable, strongly accurate, and theoretically efficient (i.e., polynomial-time). We do not believe they outperform ... More

Higher cohomology of parabolic actions on certain homogeneous spacesDec 14 2013We show that for a parabolic R^d-action on a compact quotient of PSL(2,R)^d, the cohomologies in degrees 1 through d-1 trivialize, and we give the obstructions to solving the degree-d coboundary equation, along with bounds on Sobolev norms of primitives. ... More

Instanton Solutions from Abelian Sinh-Gordon and Tzitzeica VorticesDec 29 2014Sep 22 2015We study the Abelian Higgs vortex solutions to the sinh-Gordon equation and the elliptic Tzitzeica equation. Starting from these particular vortices, we construct solutions to the Taubes equation with higher vortex number, on surfaces with conical singularities. ... More

Khintchine's Theorem with random fractionsAug 09 2017Dec 17 2018We prove versions of Khintchine's Theorem (1924) for approximations by rational numbers whose numerators lie in randomly chosen sets of integers, and we explore the extent to which the monotonicity assumption can be removed. Roughly speaking, we show ... More

Pesin's Entropy Formula for $C^1$ non-uniformly expanding mapsJul 13 2017Jan 18 2019We prove existence of equilibrium states with special properties for a class of distance expanding local homeomorphisms on compact metric spaces and continuous potentials. Moreover, we formulate a C$^1$ generalization of Pesin's Entropy Formula: all ergodic ... More

Stochastic thermodynamics of quantum maps with and without equilibriumApr 20 2017Oct 01 2017We study stochastic thermodynamics for a quantum system of interest whose dynamics are described by a completely positive trace-preserving (CPTP) map as a result of its interaction with a thermal bath. We define CPTP maps with equilibrium as CPTP maps ... More

Condition number and matricesMar 13 2017It is well known the concept of the condition number $\kappa(A) = \|A\|\|A^{-1}\|$, where $A$ is a $n \times n$ real or complex matrix and the norm used is the spectral norm. Although it is very common to think in $\kappa(A)$ as "the" condition number ... More

The Frobenius exponent of Cartier subalgebrasNov 08 2018Let $R$ be a standard graded finitely generated algebra over an $F$-finite field of prime characteristic, localized at its maximal homogeneous ideal. In this note, we prove that that Frobenius complexity of $R$ is finite. Moreover, we extend this result ... More

Bounded Model Checking of State-Space Digital Systems: The Impact of Finite Word-Length Effects on the Implementation of Fixed-Point Digital Controllers Based on State-Space ModelingOct 31 2016The extensive use of digital controllers demands a growing effort to prevent design errors that appear due to finite-word length (FWL) effects. However, there is still a gap, regarding verification tools and methodologies to check implementation aspects ... More

First-order justification logic with constant domain semanticsAug 29 2018Justification logic is a term used to identify a relatively new family of modal-like logics. There is an established literature about propositional justification logic, but incursions on the first-order case are scarce. In this paper we present a constant ... More

Learning non-Gaussian Time Series using the Box-Cox Gaussian ProcessMar 19 2018Gaussian processes (GPs) are Bayesian nonparametric generative models that provide interpretability of hyperparameters, admit closed-form expressions for training and inference, and are able to accurately represent uncertainty. To model general non-Gaussian ... More

Topology of Spaces of Valuations and Geometry of SingularitiesNov 10 2017Given an algebraic variety X defined over an algebraically closed field, we study the space RZ(X,x) consisting of all the valuations of the function field of X which are centered in a closed point x of X. We concentrate on its homeomorphism type. We prove ... More

Spectral Mixture Kernels for Multi-Output Gaussian ProcessesSep 05 2017Nov 03 2017Early approaches to multiple-output Gaussian processes (MOGPs) relied on linear combinations of independent, latent, single-output Gaussian processes (GPs). This resulted in cross-covariance functions with limited parametric interpretation, thus conflicting ... More

Vacuum-enhanced optical nonlinearities with organic molecular photoswitchesApr 05 2018We propose a cavity QED scheme to enable cross-phase modulation between two arbitrarily weak classical fields in the optical domain, using organic molecular photoswitches as a disordered intracavity nonlinear medium. We show that a long-lived vibrational ... More

Improved convergence of Complex Langevin simulationsOct 17 2017The sign problem appears in lattice QCD as soon as a non-zero chemical potential is introduced. This prevents direct simulations to determine the phase structure of the strongly interacting matter. Complex Langevin methods have been successfully used ... More

Existence and Approximability Results for variational problems under uniform constraints on the gradient by power penaltyMay 28 2014Variational problems under uniform quasiconvex constraints on the gradient are studied. In particular, existence of solutions to such problems is proved as well as existence of lagrange multipliers associated to the uniform constraint. They are shown ... More

Weak forms of topological and measure theoretical equicontinuity: relationships with discrete spectrum and sequence entropyFeb 28 2014Sep 15 2015We define weaker forms of topological and measure theoretical equicontinuity for topological dynamical systems and we study their relationships with systems with discrete spectrum and zero sequence entropy. In the topological category we show systems ... More

Free Energy Evaluation in Polymer Translocation via Jarzynski EqualityJan 31 2014Apr 21 2014We perform, with the help of cloud computing resources, extensive Langevin simulations which provide free energy estimates for unbiased three dimensional polymer translocation. We employ the Jarzynski equality in its rigorous setting, to compute the variation ... More

Power of earthquake cluster detection testsApr 05 2012Testing the global earthquake catalogue for indications of non-Poissonian attributes has been an area of intense research, especially since the 2011 Tohoku earthquake. The usual approach is to test statistically for the hypothesis that the global earthquake ... More

Stiefel tropical linear spacesMay 27 2013May 31 2015The tropical Stiefel map associates to a tropical matrix A its tropical Pluecker vector of maximal minors, and thus a tropical linear space L(A). We call the L(A)s obtained in this way Stiefel tropical linear spaces. We prove that they are dual to certain ... More

Counting the Number of Minimal Paths in Weighted Coloured-Edge GraphsDec 13 2011A weighted coloured-edge graph is a graph for which each edge is assigned both a positive weight and a discrete colour, and can be used to model transportation and computer networks in which there are multiple transportation modes. In such a graph paths ... More

On the combinatorics of commutators of Lie algebrasSep 29 2016Nov 26 2018Motivated by the combinatorial properties of products in Lie algebras, we investigate the subset of permutations that naturally appears when we write the long commutator $[x_1, x_2, ..., x_m]$ as a sum of associative monomials. We characterize this subset ... More

Polarization-driven spin precession of mesospheric sodium atomsSep 11 2018We report experimental results on the first on-sky observation of atomic spin precession of mesospheric sodium driven by polarization modulation of a continuous-wave laser. The magnetic resonance was remotely detected from the ground by observing the ... More

Non-equilibrium Lorentz gas on a curved spaceJan 12 2007The periodic Lorentz gas with external field and iso-kinetic thermostat is equivalent, by conformal transformation, to a billiard with expanding phase-space and slightly distorted scatterers, for which the trajectories are straight lines. A further time ... More

Natural braneworld inflation and baryogenesisNov 26 2004May 29 2005In natural inflation models, the inflaton is a pseudo Nambu-Goldstone boson and the flatness of the potential is protected by shift symmetries. In this framework, a successful inflation requires the global symmetry to be spontaneously broken at a scale ... More

Asymptotic almost-equivalence of abstract evolution systemsApr 14 2009We study the asymptotic behavior of almost-orbits of abstract evolution systems in Banach spaces with or without a Lipschitz assumption. In particular, we establish convergence, convergence in average and almost-convergence of almost-orbits both for the ... More

Fields of Parametrization and Optimal Affine Reparametrization of Rational CurvesOct 30 2008In this paper we present three related results on the subject of fields of parametrization. Let C be a rational curve over a field of characteristic zero. Let K be a field finitely generated over Q, such that it is a field of definition of C but not a ... More

Rescaling, thinning or complementing? On goodness-of-fit procedures for point process models and Generalized Linear ModelsNov 18 2010Generalized Linear Models (GLMs) are an increasingly popular framework for modeling neural spike trains. They have been linked to the theory of stochastic point processes and researchers have used this relation to assess goodness-of-fit using methods ... More

Metrisability of Painlevé equationsApr 12 2016We solve the metrisability problem for the six Painlev\'e equations, and more generally for all 2nd order ODEs with Painlev\'e property, and determine for which of these equations their integral curves are geodesics of a (pseudo) Riemannian metric on ... More

On the M-theory description of supersymmetric gluodynamicsMar 08 2007Jul 13 2007We study the stringy description of N=1 supersymmetric SU(N) gauge theory on R^{1,2} X S^1. Our description is based on the known Klebanov-Strassler and Maldacena-Nunez solutions, properly modified to account for the compact dimension. The presence of ... More

A sampling theorem for functions in Besov spaces on spaces of homogeneous typeJun 29 2017In this work we establish a sampling theorem for functions in Besov spaces on spaces of homogeneous type as defined in [HY] in the spirit of their recent counterpart for R d established by Jaming-Malinnikova in [JM]. The main tool is the wavelet decomposition ... More

Dissipation in small systems: A Landau-Zener approachFeb 05 2016We establish a stochastic thermodynamics for a Fermionic level driven by a time-dependent force and interacting with initially thermalized levels playing the role of a reservoir. The driving induces consecutive avoided crossings between system and reservoir ... More