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Results for "Luis Fernández Barquín"

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Dipolar-coupled moment correlations in clusters of magnetic nanoparticlesMar 05 2018Oct 30 2018Here, we investigate the nature of the moment coupling between 10-nm DMSA-coated magnetic nanoparticles, in both colloidal dispersion and in powder form. The individual iron oxide cores were composed of > 95% maghemite and agglomerated to clusters. At ... More
The magnetic structure factor of correlated nanoparticle moments in small-angle neutron scatteringApr 12 2019Here, we derive expressions for the magnetic small-angle neutron scattering (SANS) cross section of magnetic nanoparticle ensembles under consideration of a magnetic structure factor. We show that for structurally disordered ensembles with correlated ... More
Controllability properties for some semilinear parabolic PDE with a quadratic gradient termFeb 03 2012We study several controllability properties for some semilinear parabolic PDE with a quadratic gradient term. For internal distributed controls, it is shown that the system is approximately and null controllable. The proof relies on the Cole-Hopf transformation. ... More
Some relationships between intrinsic and extrinsic invariants of submanifolds in generalized S-space-formsJun 07 2013We establish some inequalities of Chen's type between certain intrinsic invariants (involving sectional, Ricci and scalar curvatures) and the squared mean curvature of submanifolds tangent to the structure vector fields of a generalized S-space-form and ... More
Reconstruction of the neutron star equation of state from w-quasinormal modes spectra with a piecewise polytropic meshing and refinement methodJan 30 2019Apr 23 2019In this paper we present a new approach to the inverse problem for relativistic stars using quasinormal modes and the piecewise polytropic parametrization of the equation of state. The algorithm is a piecewise polytropic meshing and refinement method ... More
Piecewise polytropic meshing and refinement method for the reconstruction of the neutron star equation of state using tidal deformabilities and constraints in the piecewise polytropic parameters given by the GW170817 eventMar 21 2019In this paper we present a new approach to the inverse problem for relativistic stars using the piecewise polytropic parametrization of the equation of state. The algorithm is a piecewise polytropic meshing and refinement method that reconstructs the ... More
Contact 5-manifolds with SU(2)-structureJun 04 2007Jun 20 2008We consider 5-manifolds with a contact form arising from a hypo structure, which we call \emph{hypo-contact}. We provide conditions which imply that there exists such a structure on an oriented hypersurface of a 6-manifold with a half-flat SU(3)-structure. ... More
Bianchi type A hyper-symplectic and hyper-Kähler metrics in 4DFeb 08 2011Nov 30 2011We present a simple explicit construction of hyper-Kaehler and hyper-symplectic (also known as neutral hyper-Kaehler or hyper-parakaehler) metrics in 4D using the Bianchi type groups of class A. The construction underlies a correspondence between hyper-Kaehler ... More
Uniqueness of Limit Cycles for Quadratic Vector FieldsSep 04 2017This article deals with the study of the number of limit cycles surrounding a critical point of a quadratic planar vector field, which, in normal form, can be written as $x'= a_1 x-y-a_3x^2+(2 a_2+a_5)xy + a_6 y^2$, $y'= x+a_1 y + a_2x^2+(2 a_3+a_4)xy ... More
Strongly misaligned triple system in SR 24 revealed by ALMAJul 04 2017We report the detection of the 1.3 mm continuum and the molecular emission of the disks of the young triple system SR24 by analyzing ALMA (The Atacama Large Millimeter/Submillimter Array) subarcsecond archival observations. We estimate the mass of the ... More
Non-Kaehler Heterotic String Compactifications with non-zero fluxes and constant dilatonApr 10 2008Jun 17 2008We construct new explicit compact supersymmetric valid solutions with non-zero field strength, non-flat instanton and constant dilaton to the heterotic equations of motion in dimension six. We present balanced Hermitian structures on compact nilmanifolds ... More
The L-sectional curvature of S-manifoldsFeb 08 2013Apr 22 2013We investigate L-sectional curvature of S-manifolds with respect to the Rieman- nian connection and to certain semi-symmetric metric and non-metric connections naturally related with the structure, obtaining conditions for them to be constant and giving ... More
Dynamic analysis in Greenberg's traffic modelMay 26 2017Based on the classical traffic model by Greenberg, a linear differential equation, we analyze it by means of varying the critical velocity $v_o$ that appears in it as a parameter. In order to make such analysis we have obtained a solution for such a model ... More
ALMA Reveals A Collision Between Protostellar Outflows in BHR71Apr 02 2018Apr 03 2018For a binary protostellar outflow system in which its members are located so close to each other (the separation being smaller than the addition of the widths of the flows) and with large opening angles, the collision seems unavoidable regardless of the ... More
On the local monodromy of A-hypergeometric functions and some monodromy invariant subspacesJul 15 2016Jul 18 2016We study the local monodromy of A-hypergeometric functions with respect to small loops around a coordinate hyperplane $x_i = 0$ for nonresonant parameters. In particular we obtain a formula for the characteristic polynomial of this local monodromy which ... More
Asymptotic normality and greatest common divisorsFeb 10 2013May 08 2013We report on some statistical regularity properties of greatest common divisors: for large random samples of integers, the number of coprime pairs and the average of the gcd's of those pairs are approximately normal, while the maximum of those gcd's (appropriately ... More
A moduli approach to quadratic Q-curves realizing projective mod p Galois representationsJun 03 2005For a fixed odd prime p and a representation \rho of the absolute Galois group of Q into the projective group PGL(2,p), we provide the twisted modular curves whose rational points supply the quadratic Q-curves of degree N prime to p that realize \rho ... More
Versions of the Central Sets Theorem with higher degree termsNov 03 2017Jun 12 2018We explain how Furstenberg's Central Sets Theorem can be seen as a Ramsey-theoretic result that provides us, given a specific colouring of $\mathbb N$, with a specific sequence of polynomials of degree one satisfying certain strong monochromaticity condition. ... More
An estinatiion for the essential norm of Compositiion operators acting on Bloch-type spacesJan 13 2013Let \mu be any weight function defined on the unit disk $\Bbb D$ and let $\phi$ be an analytic self-map of $\Bbb D$. In the present paper we show that the essential norm of composition operator $C_\phi$ mapping from the $\alpha$-Bloch space, with $\alpha ... More
A note on the computation of the Frobenius number of a numerical semigroupJul 06 2011Feb 09 2014In this note we observe that the Frobenius number and therefore the conductor of a numerical semigroup can be obtained from the maximal socle degree of the quotient of the corresponding semigroup algebra by the ideal generated by the biggest generator ... More
Bounded superposition operators between weighted Banach spaces of analytic functionsMar 27 2012Sep 28 2012We characterize all entire functions that transform a weighted Banach spaces of analytic functions $\mathcal{H}^{\infty}_{\mu_1}$ into another space of the same kind $\mathcal{H}^{\infty}_{\mu_2}$ by superposition for very general weights $\mu_1$ and ... More
On multi-index filtrations associated to Weierstrass semigroupsDec 19 2013The aim of this paper is to review the main techniques in the computation of Weierstra\ss semigroup at several points of curves defined over perfect fields, with special emphasis on the case of two points. Some hints about the usage of some packages of ... More
Alzheimer's Disease Diagnosis Based on Cognitive Methods in Virtual Environments and Emotions AnalysisOct 25 2018Dementia is a syndrome characterised by the decline of different cognitive abilities. Alzheimer's Disease (AD) is the most common dementia affecting cognitive domains such as memory and learning, perceptual-motion or executive function. High rate of deaths ... More
Uniqueness Properties for Discrete equations and Carleman estimatesSep 28 2015Using Carleman estimates, we give a lower bound for solutions to the discrete Schr\"odinger equation in both dynamic and stationary settings that allows us to prove uniqueness results, under some assumptions on the decay of the solutions.
The TP3-WFS: a new guy in townNov 14 2018The TP3-WFS (Two Pupil Plane Positions Wavefront Sensor) is, to the best of the authors' knowledge, the first physical implementation of the geometrical wavefront reconstruction algorithm that has been tested in a telescope as part of an actual AO-enabled ... More
Soliton almost Kähler structures on 6-dimensional nilmanifolds for the symplectic curvature flowMar 21 2013Jun 26 2013The aim of this paper is to study self-similar solutions to the symplectic cuvature flow on 6-dimensional nilmanifolds. For this purpose, we focus our attention in the family of symplectic Two- and Three-step nilpotent Lie algebras admitting a "minimal ... More
Functions and differentials on the non-split Cartan modular curve of level 11Nov 24 2014The genus $4$ modular curve $X_{ns}(11)$ attached to a non-split Cartan group of level $11$ admits a model defined over $\mathbb{Q}$. We compute generators for its function field in terms of Siegel modular functions. We also show that its Jacobian is ... More
Fractional ideals and integration with respect to the generalised Euler characteristicJun 29 2011Let $b$ be a fractional ideal of a one-dimensional Cohen-Macaulay local ring $O$ containing a perfect field $k$. This paper is devoted to the study some $O$-modules associated with $b$. In addition, different motivic Poincar\'e series are introduced by ... More
Poincaré series for plane curve singularities and their behaviour under projectionsJul 06 2011Our purpose is to investigate all defined Poincar\'e series associated with multi-index filtrations and value semigroups of curve singularities---not necessarily complex---with regard to the property of forgetting variables, i.e., by making variables ... More
On the coefficients of the Stöhr Zeta FunctionJun 29 2011Let $O$ be a one-dimensional Cohen-Macaulay local ring having a finite field as a coefficient field. The aim of this work is to extend the explicit computations of the St\"ohr Zeta Function of $O$ for one and two branches to an arbitrary number of them, ... More
Characteristic cycles and Gevrey series solutions of $A$-hypergeometric systemsFeb 12 2019We compute the $L$-characteristic cycle of an $A$-hypergeometric system and higher Euler-Koszul homology modules of the toric ring. We also prove upper semicontinuity results about the multiplicities in these cycles and apply our results to analyze the ... More
An extension problem related to the fractional LaplacianAug 25 2006Feb 13 2007The operator square root of the Laplacian $(-\lap)^{1/2}$ can be obtained from the harmonic extension problem to the upper half space as the operator that maps the Dirichlet boundary condition to the Neumann condition. In this paper we obtain similar ... More
Non-commutative Courant algebroids and Quiver algebrasMay 11 2017In this paper, we develop a differential-graded symplectic (Batalin-Vilkovisky) version of the framework of Crawley-Boevey, Etingof and Ginzburg on noncommutative differential geometry based on double derivations to construct non-commutative analogues ... More
Feasible combinatorial matrix theoryMar 26 2013We show that the well-known Konig's Min-Max Theorem (KMM), a fundamental result in combinatorial matrix theory, can be proven in the first order theory $\LA$ with induction restricted to $\Sigma_1^B$ formulas. This is an improvement over the standard ... More
The Segre cone of Banach spaces and multilinear operatorsApr 27 2018We prove that any pair of reasonable cross norms defined on the tensor product of $n$ Banach spaces induce $(2k)^{n-1}$-Lipschitz equivalent metrics (and thus, a unique topology) on the set $S^k_{X_1,\ldots, X_n}$ of vectors of rank $\leq k$. With this, ... More
On non-formal simply connected manifoldsDec 10 2002Jan 24 2003We construct examples of non-formal simply connected and compact oriented manifolds of any dimension bigger or equal to 7.
Generalised Poincaré series and embedded resolution of curvesJul 06 2011The purpose of this paper is to extend the notions of generalised Poincar\'e series and divisorial generalised Poincar\'e series (of motivic nature) introduced by Campillo, Delgado and Gusein-Zade for complex curve singularities to curves defined over ... More
On some curve singularity invariants and reductionsJul 03 2011This paper deals with the study of the behaviour of the value semigroup of a curve singularity define over a global field reduced modulo a maximal ideal. We also define a global zeta function of the curve by means of motivic integration over a suitable ... More
Time resolution studies for scintillating plastics coupled to silicon photo-multipliersJan 15 2019We present results for time resolution studies performed on three different scintillating plastics and two silicon photo-multipliers. These studies are intended to determine whether scintillating plastic/silicon photo-multiplier systems can be employed ... More
A non local Monge-Ampere equationOct 01 2014Jun 26 2015We introduce a non local analog to the Monge-Ampere operator and show some of its properties. We prove that a global problem involving this operator has C 1,1 solutions in the full space.
$A_\infty$ structures and Massey productsMay 19 2017Jan 11 2018We study the relationship between the higher Massey products on the cohomology $H$ of a differential graded algebra, and the $A_\infty$ structures induced on $H$ via homotopy transfer techniques.
Vacuum polarization of the quantized massive scalar field in the global monopole spacetime II: the renormalized quantum stress energy tensorApr 19 2019This paper is devoted to the construction of the renormalized quantum stress energy tensor $\left<T_{\mu}^{\nu}\right>_{ren}$ for a massive scalar field with arbitrary coupling to the gravitational field of a pointlike global monopole, using the Schwinger-DeWitt ... More
Hindman's Theorem is only a countable phenomenonJun 18 2015Oct 04 2016We pursue the idea of generalizing Hindman's Theorem to uncountable cardinalities, by analogy with the way in which Ramsey's Theorem can be generalized to weakly compact cardinals. But unlike Ramsey's Theorem, the outcome of this paper is that the natural ... More
Strongly Summable Ultrafilters, Union Ultrafilters, and the Trivial Sums PropertyJun 23 2013May 14 2015We answer two questions of Hindman, Stepr\=ans and Strauss, namely we prove that every strongly summable ultrafilter on an abelian group is sparse and has the trivial sums property. Moreover we show that in most cases the sparseness of the given ultrafilter ... More
Einstein almost cokähler manifoldsSep 15 2014Jan 08 2016We study an odd-dimensional analogue of the Goldberg conjecture for compact Einstein almost K\"ahler manifolds. We give an explicit non-compact example of an Einstein almost cok\"ahler manifold that is not cok\"ahler. We prove that compact Einstein almost ... More
Classification of Nilsoliton metrics in dimension sevenNov 17 2013The aim of this paper is to classify Ricci soliton metrics on $7$-dimensional nilpotent Lie groups. It can be considered as a continuation of our paper in [Transformation Groups, Volume 17, Number 3 (2012), 639--656]. To this end, we use the classification ... More
Nonlinear and spin-glass susceptibilities of three site-diluted systemsAug 13 2011The nonlinear magnetic $\chi_{3}$ and spin-glass $\chi_{sg}$ susceptibilities in zero applied field are obtained, from tempered Monte Carlo simulations, for three different spin glasses (SGs) of Ising spins with quenched site disorder. We find that the ... More
The universal zeta function for curve singularities and its relation with global zeta functionsMar 02 2017The purpose of this note is to give a brief overview on zeta functions of curve singularities and to provide some evidences on how these and global zeta functions associated to singular algebraic curves over perfect fields relate to each other.
Symplectic nilmanifolds with a symplectic non-free $Z_3$-actionJun 22 2005Dec 12 2006This paper expands some of the issues of the paper math.SG/0506449. We introduce a new technique to produce symplectic manifolds, by taking a symplectic non-free action of a finite group on a symplectic manifold and resolving symplectically the singularities ... More
Harmonic Oscillator SUSY Partners and Evolution LoopsMay 28 2012Jul 11 2012Supersymmetric quantum mechanics is a powerful tool for generating exactly solvable potentials departing from a given initial one. If applied to the harmonic oscillator, a family of Hamiltonians ruled by polynomial Heisenberg algebras is obtained. In ... More
Stable ordered union ultrafilters and $\mathrm{cov}(\mathcal{M})<\mathfrak c$Oct 19 2018Mar 24 2019A union ultrafilter is an ultrafilter over the finite subsets of $\omega$ that has a base of sets of the form $\mathrm{FU}(X)$, where $X$ is an infinite pairwise disjoint family and $\mathrm{FU}(X)=\{\bigcup F\big|F\in[X]^{<\omega}\setminus\{\varnothing\}\}$. ... More
Every strongly summable ultrafilter on $\bigoplus\mathbb Z_2$ is sparseFeb 22 2013Mar 25 2013We investigate the possibility of the existence of nonsparse strongly summable ultrafilters on certain abelian groups. In particular, we show that every strongly summable ultrafilter on the countably infinite Boolean group is sparse. This answers a question ... More
Automatic Evaluation of Neural Personality-based ChatbotsSep 30 2018Stylistic variation is critical to render the utterances generated by conversational agents natural and engaging. In this paper, we focus on sequence-to-sequence models for open-domain dialogue response generation and propose a new method to evaluate ... More
Geometry of the moduli of parabolic bundles on elliptic curvesNov 16 2016The goal of this paper is the study of simple rank 2 parabolic vector bundles over a $2$-punctured elliptic curve $C$. We show that the moduli space of these bundles is a non-separated gluing of two charts isomorphic to $\mathbb{P}^1 \times \mathbb{P}^1$. ... More
Behavior of Friedmann-Lemaitre-Robertson-Walker SingularitiesMar 09 2016A regularization procedure has been recently suggested for regularizing Big Bang singularities in Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetimes. We argue that this procedure is only appliable to one case of Big Bang singularities and does not ... More
Cyclic $A_{\infty}$-algebras and double Poisson algebrasFeb 02 2019In this article we prove that there exists an explicit bijection between nice $d$-pre-Calabi-Yau algebras and $d$-double Poisson differential graded algebras, where $d \in \mathbb{Z}$, extending a result proved by N. Iyudu and M. Kontsevich. We also show ... More
On permutation symmetry of atomic and molecular wavefunctionsApr 12 2019In this paper we analyze a recently proposed approach for the construction of antisymmetric functions for atomic and molecular systems. It is based on the assumption that the main problems with Hartree-Fock wavefunctions stem from their lack of proper ... More
The Maximin Support Method: An Extension of the D'Hondt Method to Approval-Based Multiwinner ElectionsSep 17 2016Sep 05 2018We propose the maximin support method, a novel extension of the D'Hondt apportionment method to approval-based multiwinner elections. The maximin support method is based on maximizing the support of the least supported elected candidate. It can be computed ... More
Divergence Measure Between Chaotic AttractorsNov 14 2000We propose a measure of divergence of probability distributions for quantifying the dissimilarity of two chaotic attractors. This measure is defined in terms of a generalized entropy. We illustrate our procedure by considering the effect of additive noise ... More
$K(π,1)$ conjecture for Artin groupsNov 30 2012The purpose of this paper is to put together a large amount of results on the $K(\pi,1)$ conjecture for Artin groups, and to make them accessible to non-experts. Firstly, this is a survey, containing basic definitions, the main results, examples and an ... More
The proof of Birman's conjecture on singular braid monoidsJun 30 2003Sep 29 2004Let B_n be the Artin braid group on n strings with standard generators sigma_1, ..., sigma_{n-1}, and let SB_n be the singular braid monoid with generators sigma_1^{+-1}, ..., sigma_{n-1}^{+-1}, tau_1, ..., tau_{n-1}. The desingularization map is the ... More
A variation on the homological nerve theoremSep 12 2016An equivalent but useful version on the Homological Nerve Theorem is proved.
Nilpotent Types and Fracture Squares in Homotopy Type TheoryMar 08 2019We develop the basic theory of nilpotent types and their localizations away from sets of numbers in Homotopy Type Theory. For this, general results about the classifying spaces of fibrations with fiber an Eilenberg-Mac Lane space are proven. We also construct ... More
Fluid--Gravity Correspondence under the presence of viscosityJun 18 2012The present work addresses the analogy between the speed of sound of a viscous, barotropic, and irrotational fluid and the equation of motion for a non--massive field in a curved manifold. It will be shown that the presence of viscosity implies the introduction, ... More
Fast Compatibility Testing for Phylogenies with Nested TaxaMay 06 2016Semi-labeled trees are phylogenies whose internal nodes may be labeled by higher-order taxa. Thus, a leaf labeled Mus musculus could nest within a subtree whose root node is labeled Rodentia, which itself could nest within a subtree whose root is labeled ... More
Strongly productive ultrafilters on semigroupsSep 14 2013Aug 06 2015We prove that if S is a commutative semigroup with well founded universal semilattice or a solvable inverse semigroup with well founded semilattice of idempotents, then every strongly productive ultrafilter on S is idempotent. Moreover we show that any ... More
Nonlinear fractional Laplacian problems with nonlocal "gradient terms"Dec 02 2018Let $\Omega \subset \mathbb{R}^N$, $N \geq 2$, be a smooth bounded domain. For $s \in (1/2,1)$, we consider a problem of the form \[ \left\{\begin{aligned} (-\Delta)^s u & = \mu(x)\, \mathbb{D}_s^{2}(u) + \lambda f(x)\,, & \quad \mbox{in} \Omega,\\ u ... More
Magnitude and size distribution of long-period comets in Earth-crossing or approaching orbitsApr 10 2012We analyse the population of near-Earth Long-Period Comets (LPCs) (perihelion distances q < 1.3 AU and orbital periods P > 10^3 yr). We have considered the sample of LPCs discovered during the period 1900-2009 and their estimated absolute total visual ... More
Braiding for categorical algebras and crossed modules of algebras II: Leibniz algebrasApr 25 2018In this paper we study the category of braided categorical Leibniz algebras and braided crossed modules of Leibniz algebras and we relate these structures with the categories of braided categorical Lie algebras and braided crossed modules of Lie algebras ... More
On the modularity of rigid Calabi-Yau threefolds: EpilogueAug 10 2009Jun 15 2010In a recent preprint of F. Gouvea and N. Yui (see arXiv:0902.1466) a detailed account is given of a patching argument due to Serre that proves that the modularity of all rigid Calabi-Yau threefolds defined over the rationals follows from Serre's modularity ... More
Appendix to: The level 1 weight 2 case of Serre's conjecture - a strategy for a proofDec 08 2004In this appendix, we observe that our March preprint on Serre's conjecture was indeed correct: the only "missing argument" follows automatically from a result of Bockle and Ramakrishna. Thus, we get a proof of the level 1 weight 2 case of Serre's conjecture ... More
Existence of non-elliptic mod l Galois representations for every l >5Apr 02 2004For $\ell = 3$ and 5 it is known that every odd, irreducible, 2-dimensional representation of $\Gal(\bar{\Q}/\Q)$ with values in $\F_\ell$ and determinant equal to the cyclotomic character must "come from" the $\ell$-torsion points of an elliptic curve ... More
Anomalous massless modesDec 04 2014Some years ago Anton Yu. Alekseev et al. conjectured the existence of massless modes in the spectrum of excitations ("anomalous massless modes") building upon certain similarities between a spontaneous symmetry breaking and the interplay of axial and ... More
The Lagrangian cobordism group of $T^2$Oct 30 2013Nov 25 2014We compute the Lagrangian cobordism group of the standard symplectic 2-torus and prove that it is isomorphic to the Grothendieck group of its derived Fukaya category. The proofs use homological mirror symmetry for the 2-torus.
Spectral methods for orthogonal rational functionsApr 25 2007An operator theoretic approach to orthogonal rational functions on the unit circle with poles in its exterior is presented in this paper. This approach is based on the identification of a suitable matrix representation of the multiplication operator associated ... More
On the question of embedding a semigroup into an idempotent generated oneMay 15 2012In this paper we present a new embedding of a semigroup into a semiband (idempotent-generated semigroup) of depth 4 (every element is the product of 4 idempotents) using a semidirect product construction. Our embedding does not assume that S is a monoid ... More
Solving diophantine equations x^4 + y^4 = q z^pApr 27 2003We give a method to solve generalized Fermat equations of type $x^4 + y^4 = q z^p$, for some prime values of $q$ and every prime $p$ bigger than 13. We illustrate the method by proving that there are no solutions for $q= 73, 89$ and 113.
On unique continuation for solutions of the Schr{ö}dinger equation on treesJun 27 2017Mar 22 2018We prove that if a solution of the time-dependent Schr{\"o}dinger equation on an homogeneous tree with bounded potential decays fast at two distinct times then the solution is trivial. For the free Schr{\"o}dinger operator, we use the spectral theory ... More
Gruff UltrafiltersApr 08 2016Oct 01 2017We investigate the question of whether $\mathbb Q$ carries an ultrafilter generated by perfect sets (such ultrafilters were called gruff ultrafilters by van Douwen). We prove that one can (consistently) obtain an affirmative answer to this question in ... More
Braiding for categorical algebras and crossed modules of algebras I: Associative and Lie algebrasNov 23 2017In this paper we study the categories of braided categorical associative algebras and braided crossed modules of associative algebras and we relate these structures with the categories of braided categorical Lie algebras and braided crossed modules of ... More
Integrable Quantum Field Theories with Unstable ParticlesOct 27 1999Nov 03 1999A new family of S-matrix theories with resonance poles is constructed and conjectured to correspond to the Homogeneous sine-Gordon theories associated with simply laced compact Lie groups, where some of the resonance poles can be traced to the presence ... More
The $dδ$--lemma for weakly Lefschetz symplectic manifoldsJan 17 2005For a symplectic manifold $(M,\omega)$, not necessarily hard Lefschetz, we prove a version of the Merkulov $d\delta$--lemma. We also study the $d\delta$--lemma and related cohomologies for compact symplectic solvmanifolds.
Committees providing EJR can be computed efficientlyApr 02 2017Apr 18 2017We identify a whole family of approval-based multi-winner voting rules that satisfy PJR. Moreover, we identify a subfamily of voting rules within this family that satisfy EJR. All these voting rules can be computed in polynomial time as long as the subalgorithms ... More
Quasiperiodicity, bistability and chaos in the Landau-Lifshitz equationMay 04 1999The dynamics of an individual magnetic moment is studied through the Landau-Lifshitz equation with a periodic driving in the direction perpendicular to the applied field. For fields lower than the anisotropy field and small values of the perturbation ... More
Monotonicity axioms in approval-based multi-winner voting rulesOct 11 2017In this paper we study several monotonicity axioms in approval-based multi-winner voting rules. We consider monotonicity with respect to the support received by the winners and also monotonicity in the size of the committee. Monotonicity with respect ... More
Monotonicity axioms in approval-based multi-winner voting rulesOct 11 2017Feb 22 2019In this paper we study several monotonicity axioms in approval-based multi-winner voting rules. We consider monotonicity with respect to the support received by the winners and also monotonicity in the size of the committee. Monotonicity with respect ... More
Reconstruction of the neutron star equation of state from w-quasinormal modes spectra with a piecewise polytropic meshing and refinement methodJan 30 2019In this paper we present a new approach to the inverse problem for relativistic stars using quasinormal modes and the piecewise polytropic parametrization of the equation of state. The algorithm is a piecewise polytropic meshing and refinement method ... More
ELDAR, a new method to identify AGN in multi-filter surveys: the ALHAMBRA test-caseJul 24 2017We present ELDAR, a new method that exploits the potential of medium- and narrow-band filter surveys to securely identify active galactic nuclei (AGN) and determine their redshifts. Our methodology improves on traditional approaches by looking for AGN ... More
On the Quantum Homology of Real Lagrangians in Fano Toric ManifoldsAug 29 2011Oct 30 2013We study the Lagrangian quantum homology of real parts of Fano toric manifolds of minimal Chern number at least 2, using coefficients in a ring of Laurent polynomials over Z/2Z. We show that these Lagrangians are wide, in the sense that their quantum ... More
Regularity of solutions of the fractional porous medium flow with exponent 1/2Sep 29 2014We study the regularity of a porous medium equation with nonlocal diffusion effects given by an inverse fractional Laplacian operator. The precise model is $u_t=\nabla\cdot(u\nabla (-\Delta)^{-1/2}u).$ For definiteness, the problem is posed in $\{x\in\mathbb{R}^N, ... More
A control theorem for the images of Galois actions on certain infinite families of modular formsJan 18 2007In this letter we show that for certain infinite families of modular forms of growing level it is possible to have a control result for the exceptional primes of the attached Galois representations. As an application, a uniform version of a result of ... More
The level 1 weight 2 case of Serre's conjectureDec 05 2004Apr 02 2007We give a proof of some small weight and level cases of Serre's conjecture.
Existence of families of Galois representations and new cases of the Fontaine-Mazur conjectureApr 27 2003In a previous article, we have proved a result asserting the existence of a compatible family of Galois representations containing a given crystalline irreducible odd two-dimensional representation. We apply this result to establish new cases of the Fontaine-Mazur ... More
Remarks on Serre's modularity conjectureMar 17 2006Apr 24 2011In this article we give a proof of Serre's conjecture for the case of odd level and arbitrary weight. Our proof does not depend on any generalization of Kisin's modularity lifting results to characteristic 2 (moreover, we will not consider at all characteristic ... More
Modularity of abelian surfaces with Quaternionic MultiplicationApr 27 2003We prove that any abelian surface defined over $\Q$ of $GL_2$-type having quaternionic multiplication and good reduction at 3 is modular. We generalize the result to higher dimensional abelian varieties with ``sufficiently many endomorphisms".
Gauge Mediation with Gauge Messengers in SU(5)Jul 21 2010Nov 18 2010The inclusion of gauge messengers in models of gauge mediation allows for more general predictions that those described by the framework of general gauge mediation. Motivated by this, we explore some models of gauge mediation with gauge messengers in ... More
Advanced Programming Platform for efficient use of Data Parallel HardwareMar 22 2012Mar 23 2012Graphics processing units (GPU) had evolved from a specialized hardware capable to render high quality graphics in games to a commodity hardware for effective processing blocks of data in a parallel schema. This evolution is particularly interesting for ... More
Residual $p$ properties of mapping class groups and surface groupsMar 23 2007Let $\mathcal M (\Sigma, \mathcal P)$ be the mapping class group of a punctured oriented surface $(\Sigma, \mathcal P)$ (where $\mathcal P$ may be empty), and let $\mathcal T_p(\Sigma,\mathcal P)$ be the kernel of the action of $\mathcal M (\Sigma, \mathcal ... More
Holder estimates for advection fractional-diffusion equationsSep 29 2010Apr 22 2011We analyse conditions for an evolution equation with a drift and fractional diffusion to have a Holder continuous solution. In case the diffusion is of order one or more, we obtain Holder estimates for the solution for any bounded drift. In the case when ... More
Maps preserving common zeros between subspaces of vector-valued continuous functionsOct 13 2009For metric spaces $X$ and $Y$, normed spaces $E$ and $F$, and certain subspaces $A(X,E)$ and $A(Y,F)$ of vector-valued continuous functions, we obtain a complete characterization of linear and bijective maps $T:A(X,E)\to A(Y,F)$ preserving common zeros, ... More