Results for "Ruben Gomez-Ojeda"

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Transient dynamics of a colloidal particle driven through a viscoelastic fluidMay 25 2015Sep 17 2015We experimentally study the transient motion of a colloidal particle actively dragged by an optical trap through different viscoelastic fluids (wormlike micelles, polymer solutions, and entangled $\lambda$-phage DNA). We observe that, after sudden removal ... More
Geometric-based Line Segment Tracking for HDR Stereo SequencesSep 25 2018In this work, we propose a purely geometrical approach for the robust matching of line segments for challenging stereo streams with severe illumination changes or High Dynamic Range (HDR) environments. To that purpose, we exploit the univocal nature of ... More
Fluctuations in an aging system: absence of effective temperature in the sol-gel transition of a quenched gelatin sampleSep 03 2015We study the fluctuations of a Brownian micro particle trapped with optical tweezers in a gelatin solution undergoing a fast local temperature quench below the sol-gel transition. Contrary to what was previously reported, we observe no anomalous fluctuations ... More
Active particles in geometrically confined viscoelastic fluidsAug 27 2019We experimentally study the dynamics of active particles (APs) in a viscoelastic fluid under various geometrical constraints such as flat walls, spherical obstacles and cylindrical cavities. We observe that the main effect of the confined viscoelastic ... More
Non-equilibrium work distribution for interacting colloidal particles under frictionJan 12 2015Mar 25 2015We experimentally investigate the distribution of the non-equilibrium work done by an external force on a mesoscopic system with many coupled degrees of freedom: a colloidal monolayer mechanically driven across a periodic light field. Since this system ... More
Finite sampling effects on generalized fluctuation-dissipation relations for steady statesFeb 10 2011We study the effects of the finite number of experimental data on the computation of a generalized fluctuation-dissipation relation around a nonequilibrium steady state of a Brownian particle in a toroidal optical trap. We show that the finite sampling ... More
Fluctuations and response in a non-equilibrium micron-sized systemJun 16 2010Nov 30 2010The linear response of non-equilibrium systems with Markovian dynamics satisfies a generalized fluctuation-dissipation relation derived from time symmetry and antisymmetry properties of the fluctuations. The relation involves the sum of two correlation ... More
Steady state fluctuation relations for systems driven by an external random forceDec 07 2009We experimentally study the fluctuations of the work done by an external Gaussian random force on two different stochastic systems coupled to a thermal bath: a colloidal particle in an optical trap and an atomic force microscopy cantilever. We determine ... More
Memory-induced transition from a persistent random walk to circular motion for achiral microswimmersJul 21 2018We experimentally study the motion of light-activated colloidal microswimmers in a viscoelastic fluid. We find that, in such a non-Newtonian environment, the active colloids undergo an unexpected transition from enhanced angular diffusion to persistent ... More
Learning-based Image Enhancement for Visual Odometry in Challenging HDR EnvironmentsJul 05 2017Apr 09 2018One of the main open challenges in visual odometry (VO) is the robustness to difficult illumination conditions or high dynamic range (HDR) environments. The main difficulties in these situations come from both the limitations of the sensors and the inability ... More
PL-SLAM: a Stereo SLAM System through the Combination of Points and Line SegmentsMay 26 2017Apr 09 2018Traditional approaches to stereo visual SLAM rely on point features to estimate the camera trajectory and build a map of the environment. In low-textured environments, though, it is often difficult to find a sufficient number of reliable point features ... More
Training a Convolutional Neural Network for Appearance-Invariant Place RecognitionMay 27 2015Place recognition is one of the most challenging problems in computer vision, and has become a key part in mobile robotics and autonomous driving applications for performing loop closure in visual SLAM systems. Moreover, the difficulty of recognizing ... More
Automatic Multi-Sensor Extrinsic Calibration for Mobile RobotsJun 11 2019In order to fuse measurements from multiple sensors mounted on a mobile robot, it is needed to express them in a common reference system through their relative spatial transformations. In this paper, we present a method to estimate the full 6DoF extrinsic ... More
The short resolution of a semigroup algebraDec 01 2015Feb 25 2017This work generalizes the short resolution given in Proc. Amer. Math. Soc. \textbf{131}, 4, (2003), 1081--1091, to any affine semigroup. Moreover, a characterization of Ap\'{e}ry sets is given. This characterization lets compute Ap\'{e}ry sets of affine ... More
Non-euclidean shadows of classical projective theoremsDec 24 2014Jan 22 2015Some translations into non-euclidean geometry of classical theorems of planar projective geometry are explored. The existence of some common triangle centers is dedeuced from theorems of Pascal and Chasles. Desargues' Theorem allows to construct a non-euclidean ... More
Dileptons and Direct Photons at SPSJul 22 2009Sep 11 2009The study of dilepton and direct photon emission was one of the main topics of the experimental program at the SPS devoted to the search of signals for QGP formation. Three generations of experiments, Helios-3, NA38/NA50, CERES and NA60 measured e+e- ... More
An alternative representation of the negative binomial-Lindley distribution. New results and applicationsMar 14 2017In this paper we present an alternative representation of the Negative Binomial--Lindley distribution recently proposed by Zamani and Ismail (2010) which shows some advantages over the latter model. This new formulation provides a tractable model with ... More
Almost symmetric numerical semigroups with given Frobenius number and typeJun 28 2018Nov 14 2018We give two algorithmic procedures to compute the whole set of almost symmetric numerical semigroups with fixed Frobenius number and type, and the whole set of almost symmetric numerical semigroups with fixed Frobenius number. Our algorithms allow to ... More
Berry phase of the Tavis-Cummings model with three modes of oscillationAug 01 2019In this paper we develop a general method to obtain the Berry phase of time-dependent Hamiltonians with a linear structure given in terms of the $SU(1,1)$ and $SU(2)$ groups. This method is based on the similarity transformations of the displacement operator ... More
Limitations Of Richardson Extrapolation For Kernel Density EstimationDec 20 2018This paper develops the process of using Richardson Extrapolation to improve the Kernel Density Estimation method, resulting in a more accurate (lower Mean Squared Error) estimate of a probability density function for a distribution of data in $R_d$ given ... More
Martingale Characterizations of Risk-Averse Stochastic Optimization ProblemsFeb 10 2018Feb 13 2018This paper addresses risk awareness of stochastic optimization problems. Nested risk measures appear naturally in this context, as they allow beneficial reformulations for algorithmic treatments. The reformulations presented extend usual Hamilton-Jacobi-Bellman ... More
Automorphism groups of origami curvesJul 24 2019A closed Riemann surface $S$ (of genus at least one) is called an origami curve if it admits a non-constant holomorphic map $\beta:S \to E$ with at most one branch value, where $E$ is a genus one Riemann surface. In this case, $(S,\beta)$ is called an ... More
HDG-NEFEM with degree adaptivity for Stokes flowsJan 20 2018The NURBS-enhanced finite element method (NEFEM) combined with a hybridisable discontinuous Galerkin (HDG) approach is presented for the first time. The proposed technique completely eliminates the uncertainty induced by a polynomial approximation of ... More
Bipartite graphs and their dessins d'enfantsNov 09 2016Aug 22 2017Each finite and connected bipartite graph induces a finite collection of non-isomorphic dessins d'enfants, that is, $2$-cell embeddings of it into some closed orientable surface. We describe an algorithm to compute all these dessins d'enfants, together ... More
Extended States in a One-dimensional Generalized Dimer ModelApr 03 2002The transmission coefficient for a one dimensional system is given in terms of Chebyshev polynomials using the tight-binding model. This result is applied to a system composed of two impurities located between $N$ sites of a host lattice. It is found ... More
Supertubes versus superconducting tubesMay 13 2005In this paper we show the relationship between cylindrical D2-branes and cylindrical superconducting membranes described by a generic effective action at the bosonic level. In the first case the extended objects considered, arose as blown up type IIA ... More
Modified pure spinors and mirror symmetryDec 08 2004It has been argued recently that mirror symmetry exchanges two pure spinors characterizing a generic manifold with SU(3)-structure. We show how pure spinors are modified in the presence of topological D-branes, so that they are still exchanged by mirror ... More
Equivariant K-homology for some Coxeter groupsApr 18 2006We obtain the equivariant K-homology of the classifying space \underline{E}W for W a right-angled or, more generally, an even Coxeter group. The key result is a formula for the relative Bredon homology of \underline{E}W in terms of Coxeter cells. Our ... More
Incremental copying garbage collection for WAM-based Prolog systemsJan 02 2006The design and implementation of an incremental copying heap garbage collector for WAM-based Prolog systems is presented. Its heap layout consists of a number of equal-sized blocks. Other changes to the standard WAM allow these blocks to be garbage collected ... More
Funneled Bayesian Optimization for Design, Tuning and Control of Autonomous SystemsOct 02 2016Feb 05 2019Bayesian optimization has become a fundamental global optimization algorithm in many problems where sample efficiency is of paramount importance. Recently, there has been proposed a large number of new applications in fields such as robotics, machine ... More
Equivalence of the Traditional and Non-Standard Definitions of Concepts from Real AnalysisJun 06 2014ACL2(r) is a variant of ACL2 that supports the irrational real and complex numbers. Its logical foundation is based on internal set theory (IST), an axiomatic formalization of non-standard analysis (NSA). Familiar ideas from analysis, such as continuity, ... More
N=2 higher-derivative couplings from stringsNov 19 2013We consider the Calabi-Yau reduction of the Type IIA eight derivative one-loop stringy corrections focusing on the couplings of the four dimensional gravity multiplet with vector multiplets and a tensor multiplet containing the NS two-form. We obtain ... More
D-brane couplings and Generalised GeometryJan 30 2013The goal of this paper is to re-examine D-brane Ramond-Ramond field couplings in the presence of a B-field. We will argue that the generalised geometry induced on the world volume by the B-field results in an important but subtle change on the coupling. ... More
Conformal invariant interaction of a scalar field with the higher spin field in AdS_{D}Feb 28 2009May 19 2010The explicit form of linearized gauge invariant interactions of scalar and general higher even spin fields in the $AdS_{D}$ space is obtained. In the case of general spin $\ell$ a generalized 'Weyl' transformation is proposed and the corresponding 'Weyl' ... More
Ageing of a space-based CCD: photometric performance development of the low Earth orbiting detectors of the CoRoT missionSep 08 2016In this thesis we have analysed the time evolution of the photometric precision achieved by the space-based exoplanet-hunting mission CoRoT during its flight phase (2007-2012). This study of the noise level of CoRoT light curves has been based on a previous ... More
The Fundamental Theorem of Algebra in ACL2Oct 10 2018We report on a verification of the Fundamental Theorem of Algebra in ACL2(r). The proof consists of four parts. First, continuity for both complex-valued and real-valued functions of complex numbers is defined, and it is shown that continuous functions ... More
Dark matter bound states via emission of scalar mediatorsAug 14 2018Jan 14 2019If dark matter (DM) couples to a force carrier that is much lighter than itself, then it may form bound states in the early universe and inside haloes. While bound-state formation via vector emission is known to be efficient and have a variety of phenomenological ... More
A Neural Network Approach for the Peak Profile CharacterizationDec 22 2016The neural network-based approach, presented in this paper, was developed for the analysis of peak profiles and for the prediction of base profile characteristics, such as width, asymmetry, asymptotic ("peak tales"), etc. of the observed distributions. ... More
Lyalpha heating and its impact on early structure formationJul 24 2007In this paper we have calculated the effect of Lyalpha photons emitted by the first stars on the evolution of the IGM temperature. We have considered both a standard Salpeter IMF and a delta-function IMF for very massive stars with mass 300 M_sun. We ... More
Holographic QCD predictions for rare B decaysJun 21 2019Jun 26 2019Light-front wavefunctions obtained from holographic light-front QCD are used to obtain the distributions amplitudes for $K^*$ vector meson. Consequently, alternate predictions for rare B transitions to $K^*$ form factors are presented. In this talk, I ... More
M-theoretic Lichnerowicz formula and supersymmetryMay 11 2017A suitable generalisation of the Lichnerowicz formula can relate the squares of supersymmetric operators to the effective action, the Bianchi identities for fluxes, and some equations of motion. Recently, such formulae have also been shown to underlie ... More
The Lie Transform Method for perturbations of contravariant antisymmetric tensor fields and its applications to Hamiltonian dynamicsAug 01 2013By means of the Schouten calculus for contravariant antisymmetric tensor fields, we apply the Lie transform method to investigate smooth deformations of tensor fields and, in particular, to perturbations of Hamiltonian systems generated by deformations ... More
Diffractive vector meson production at HERA using holographic AdS/QCD wavefunctionsMay 16 2013We demonstrate another success of the AdS/QCD correspondence by showing that an AdS/QCD holographic light-front wavefunction for the $\rho$ meson generates predictions for the cross-sections of diffractive $\rho$ production that are in agreement with ... More
How Computers Work: Computational Thinking for EveryoneJan 22 2013What would you teach if you had only one course to help students grasp the essence of computation and perhaps inspire a few of them to make computing a subject of further study? Assume they have the standard college prep background. This would include ... More
Physics inspired algorithms for (co)homology computationDec 06 2012The issue of computing (co)homology generators of a cell complex is gaining a pivotal role in various branches of science. While this issue can be rigorously solved in polynomial time, it is still overly demanding for large scale problems. Drawing inspiration ... More
Ten-dimensional lifts of global supersymmetry on curved spacesOct 30 2017Admissible curved space backgrounds for four-dimensional supersymmetric field theories are determined by solving Killing spinor equations of four-dimensional off-shell supergravities. These can be obtained by combining ten-dimensional type IIB supersymmetry ... More
Periodic first integrals for Hamiltonian systems of Lie typeApr 07 2010We prove the existence of a Lie algebra of first integrals for time dependent Hamiltonian systems of Lie type. Moreover, applying the Floquet theory for periodic Euler systems on Lie algebras, we show the existence of an abelian Lie algebra of periodic ... More
Topology Change from (Heterotic) Narain T-DualityNov 24 2008Dec 13 2008We consider Narain T-duality on a nontrivially fibered n-torus bundle in the presence of a topologically nontrivial NS H flux. The action of the duality group on the topology and H flux of the corresponding type II and heterotic string backgrounds is ... More
Mirror symmetry & supersymmetry on SU(4)-structure backgroundsJan 12 2016We revisit the backgrounds of type IIB on manifolds with $SU(4)$-structure and discuss two sets of solutions arising from internal geometries that are complex and symplectic respectively. Both can be realized in terms of generalized complex geometry. ... More
Perfect Numbers in ACL2Sep 21 2015A perfect number is a positive integer n such that n equals the sum of all positive integer divisors of n that are less than n. That is, although n is a divisor of n, n is excluded from this sum. Thus 6 = 1 + 2 + 3 is perfect, but 12 < 1 + 2 + 3 + 4 + ... More
Geometrical structure of Weyl invariants for spin three gauge field in general gravitational background in $d=4$Apr 28 2018May 20 2018We construct all possible Weyl invariant actions in $d=4$ for linearized spin three field in a general gravitational background. The first action is obtained as the square of the generalized Weyl tensor for a spin three gauge field in nonlinear gravitational ... More
Fields of definition of cyclic p-gonal curvesSep 26 2013Let $S$ be cyclic $p$-gonal Riemann surface, that is, a closed Riemann surface of genus $g \geq 2$ admitting a conformal automorphism $\varphi$ of prime order $p$ so that $S/\langle \varphi \rangle$ has genus zero. In this article we provide a short argument ... More
Cohomology in electromagnetic modelingNov 10 2011Electromagnetic modeling provides an interesting context to present a link between physical phenomena and homology and cohomology theories. Over the past twenty-five years, a considerable effort has been invested by the computational electromagnetics ... More
Discontinuous Galerkin approximations in computational mechanics: hybridization, exact geometry and degree adaptivityAug 19 2019Discontinuous Galerkin (DG) discretizations with exact representation of the geometry and local polynomial degree adaptivity are revisited. Hybridization techniques are employed to reduce the computational cost of DG approximations and devise the hybridizable ... More
A Comment on the K-theory Meaning of the Topology of Gauge FixingApr 24 2001Based on the recently discovered K-theory description of D-branes in string theory a K-theory interpretation of the topology of gauge conditions for four dimensional gauge theories, in particular 't Hooft abelian projection, is presented. The interpretation ... More
Elliptic Singularities, θ-Puzzle and Domain WallsNov 11 1997Nov 14 1997We study N=1 four dimensional gluodynamics in the context of M-theory compactifications on elliptically fibered Calabi-Yau fourfolds. Gaugino condensates, \theta-dependence, Witten index and domain walls are considered for singularities of type $\hat{A}_{n-1}$ ... More
Fast and direct visualization of piezo-generated charges at the nanoscale using direct piezoelectric force microscopySep 07 2018The denominated surface charge scraping mechanism was discovered in 2014 by using a new Atomic Force Microscopy (AFM) based mode called Charge Gradient Microscopy. The measurements to probe such mechanism are achieved with the use of a current-to-voltage ... More
Selfadjoint time operators and invariant subspacesJul 20 2006Nov 02 2006For classical dynamical systems time operators are introduced as selfadjoint operators satisfying the so called weak Weyl relation with the unitary groups of time evolution. Dynamical systems with time operators are intrinsically irreversible because ... More
A Comment on Masses, Quantum Affine Symmetries and PP-Wave BackgroundsNov 14 2002Jul 04 2003Two dimensional light cone world sheet massive models can be used to define good string backgrounds.In many cases these light cone world sheet lagrangians flow from a CFT in the UV to a theory of massive particles in the IR. The relevant symmetry in the ... More
The Role of Resonances in the Stochastic LimitJul 17 2006In the stochastic limit the resonances play a fundamental role because they determine the generalized susceptivities which are the building blocks of all the physical information which survives in this limit. There are two sources of possible divergences: ... More
$SU(1,1)$ solution for the Dunkl-Coulomb problem in two dimensions and its coherent statesSep 12 2016We study the radial part of the Dunkl-Coulomb problem in two dimensions and show that this problem possesses the $su(1,1)$ symmetry. We introduce two different realizations for the $su(1,1)$ Lie algebra and use the theory of irreducible representations ... More
The number radial coherent states for the generalized MICZ-Kepler problemOct 09 2015We study the radial part of the MICZ-Kepler problem in an algebraic way by using the $su(1,1)$ Lie algebra. We obtain the energy spectrum and the eigenfunctions of this problem from the $su(1,1)$ theory of unitary representations and the tilting transformation ... More
Affine semigroups having a unique Betti elementMar 19 2012Jun 01 2012We characterize affine semigroups having one Betti element and we compute some relevant non-unique factorization invariants for these semigroups. As an example, we particularize our description to numerical semigroups.
The nonlinear distribution of employment across municipalitiesNov 23 2018In this paper, the nonlinear distribution of employment across Spanish municipalities is analyzed. In addition, we explore the properties of the family of generalized power law (GPL) distributions, and test its adequacy for modelling employment data. ... More
A few filters are enough: Convolutional Neural Network for P300 DetectionSep 16 2019In this paper, we aim to provide elements to contribute to the discussion about the usefulness of deep CNNs with several filters to solve both within-subject and cross-subject classification for single-trial P300 detection. To that end, we present SepConv1D, ... More
IR Renormalons and Fractional Instantons in SUSY Gauge TheoriesMar 25 2004We study IR-renormalon divergences in N=1 supersymmetric Yang Mills gauge theories and in two dimensional non linear sigma models with mass gap. We derive, in both types of theories, a direct connection between IR- renormalons and fractional instanton ... More
On the Wilsonian meaning of quantum error correctionApr 24 2019We sketch a recipe to define renormalization group transformations based on Kadanoff-Wilson block packing using a quantum error correction code. In such a case the RG transformations of the couplings are determined by the error matrix of the QEC code. ... More
The Bessel-Plancherel theorem and applicationsNov 26 2012Let $G$ be a simple Lie Group with finite center, and let $K\subset G$ be a maximal compact subgroup. We say that $G$ is a Lie group of tube type if $G/K$ is a hermitian symmetric space of tube type. For such a Lie group $G$, we can find a parabolic subgroup ... More
Wave Propagation in Shallow-Water Acoustic Random WaveguidesNov 30 2009In shallow-water waveguides a propagating field can be decomposed over three kinds of modes: the propagating modes, the radiating modes and the evanescent modes. In this paper we consider the propagation of a wave in a randomly perturbed waveguide and ... More
D-Brane Probes and Mirror SymmetryDec 10 1996We study the effect of mirror symmetry for K3 surfaces on D-brane probe physics. The case of elliptically fibered K3 surfaces is considered in detail. In many cases, mirror can transform a singular fiber of Kodaira's type ADE into sets of singular fibers ... More
Loss of Resolution for the Time Reversal of Waves in Random Underwater Acoustic ChannelsJan 24 2012In this paper we analyze a time-reversal experiment in a random underwater acoustic channel. In this kind of waveguide with semi-infinite cross section a propagating field can be decomposed over three kinds of modes: the propagating modes, the radiating ... More
Probing linear and nonlinear microrheology of viscoelastic fluidsDec 16 2014Bulk rheological properties of viscoelastic fluids have been extensively studied in macroscopic shearing geometries. However, little is known when an active microscopic probe is used to locally perturb them far from the linear-response regime. Using a ... More
Coupling nuclear reaction rates with temperature in explosive conditionsOct 15 2002Oct 16 2002We present a straightforward integration method to compute the abundance and temperature evolution in explosive scenarios. In this approach the thermal equation is implicitely coupled with chemical equations in order to avoid instabilities and ensure ... More
Gauge/String Duality in Confining TheoriesFeb 02 2006Aug 31 2006This is the content of a set of lectures given at the XIII Jorge Andre Swieca Summer School on Particles and Fields, held in Campos do Jordao, Brazil in January 2005. They intend to be a basic introduction to the topic of gauge/gravity duality in confining ... More
Scalable Deep Learning on Distributed Infrastructures: Challenges, Techniques and ToolsMar 27 2019Deep Learning (DL) has had an immense success in the recent past, leading to state-of-the-art results in various domains such as image recognition and natural language processing. One of the reasons for this success is the increasing size of DL models ... More
On the isomorphism problem for even Artin groupsSep 02 2019An even Artin group is a group which has a presentation with relations of the form $(st)^n=(ts)^n$ with $n\ge 1$. With a group $G$ we associate a Lie $\mathbb Z$-algebra $\mathcal{TG}r(G)$. This is the usual Lie algebra defined from the lower central ... More
Exact Chern-Simons / Topological String dualityJun 12 2015We invoke universal Chern-Simons theory to analytically calculate the exact free energy of the refined topological string on the resolved conifold. In the unrefined limit we reproduce non-perturbative corrections for the resolved conifold found elsewhere ... More
Heterotic Sigma Models with N=2 Space-Time SupersymmetryOct 26 2010Jun 08 2012We study the non-linear sigma model realization of a heterotic vacuum with N=2 space-time supersymmetry. We examine the requirements of (0,2) + (0,4) world-sheet supersymmetry and show that a geometric vacuum must be described by a principal two-torus ... More
A framework for the comparison of different EEG acquisition solutionsOct 04 2018The purpose of this work is to propose a framework for the benchmarking of EEG amplifiers, headsets, and electrodes providing objective recommendation for a given application. The framework covers: data collection paradigm, data analysis, and statistical ... More
Towards spin injection from silicon into topological insulators: Schottky barrier between Si and Bi2Se3May 21 2012A scheme is proposed to electrically measure the spin-momentum coupling in the topological insulator surface state by injection of spin polarized electrons from silicon. As a first approach, devices were fabricated consisting of thin (<100nm) exfoliated ... More
Chaotic motion and the evolution of morphological components in a time-dependent model of a barred galaxy within a dark matter haloMar 07 2016Apr 07 2016Studies of dynamical stability (chaotic versus regular motion) in galactic dynamics often rely on static analytical models of the total gravitational potential. Potentials based upon self-consistent N-body simulations offer more realistic models, fully ... More
New Integrable Deformations of Higher Spin Heisenberg-Ising ChainsMar 12 1992We show that the anisotropic Heisenberg-Ising chains with higher spin allow, for special values of the anisotropy, integrable deformations intimately related to the theory of quantum groups at roots of unity. For the spin one case we construct and study ... More
On the String Description of ConfinementMar 23 2000Mar 27 2000A non supersymmetric string background, directly derived from the string soft dilaton theorem, is used to compute, in the semiclassical approximation, the expectation value of Wilson loops in static gauge. The resulting potential shares common features ... More
A Comment on the Holographic Renormalization Group and the Soft Dilaton TheoremJan 05 2000Jan 24 2000The equivalence between the holographic renormalization group and the soft dilaton theorem is shown for a class of wrapped metrics solutions of the string beta function equations for the bosonic string.
Nonequilibrium Chiral Dynamics and Effective LagrangiansSep 14 2001We review our recent work on Chiral Lagrangians out of thermal equilibrium, which are introduced to analyse the pion gas formed after a Relativistic Heavy Ion Collision. Chiral Perturbation Theory is extended by letting $\fpi$ be time dependent and allows ... More
Baryonic symmetries in AdS_4/CFT_3: an overviewFeb 27 2011Mar 22 2011Global symmetries play an important role in classifying the spectrum of a gauge theory. In the context of the AdS/CFT duality, global baryon-like symmetries are specially interesting. In the gravity side, they correspond to vector fields in AdS arising ... More
Branes wrapping black holes as a purely gravitational dielectric effectSep 30 2005Jan 13 2006In this paper we give a microscopical description of certain configurations of branes wrapping black hole horizons in terms of dielectric gravitational waves. Interestingly, the configurations are stable only due to the gravitational background. Therefore, ... More
Irreducibility of the moduli space of vector bundles on surfaces and Brill-Noether theory on singular curvesOct 27 1997Mar 23 2000We prove the irreducibility of the moduli space of rank 2 semistable torsion free sheaves (with a generic polarization and any value of c_2) on a K3 or a del Pezzo surface. In the case of a K3 surface, we need to prove a result on the connectivity of ... More
Global diffeomorphism of the Lagrangian flow-map defining Equatorially trapped water wavesMay 07 2015The aim of this paper is to prove that a three dimensional Lagrangian flow which defines equatorially trapped water waves is dynamically possible. This is achieved by applying a mixture of analytical and topological methods to prove that the nonlinear ... More
Study of VBF/VBS in the LHC at 13 TeV, the EFT ApproachOct 24 2016We review the current status of vector boson fusion and vector boson scattering studies in the frame of Run-2 of LHC. These processes are equally interesting and challenging, and new ideas have to be applied for their experimental analysis. These channels ... More
Effective field theories and pseudo-observables in the quest for physics beyond the Standard ModelOct 08 2015We discuss briefly the kappa framework, proposed originally as a test for the Higgs couplings of the Standard Model (SM). Further, we discuss a generalization of this idea in terms of effective field theory. We sketch how to add dimension 6 operators ... More
Stability of conic bundles (with an appendix by Mundet i Riera)Nov 25 1999Roughly speaking, a conic bundle is a surface, fibered over a curve, such that the fibers are conics (not necessarily smooth). We define stability for conic bundles and construct a moduli space. We prove that (after fixing some invariants) these moduli ... More
QCD phase diagram in nonlocal chiral quark modelsSep 08 2004The QCD phase diagram is analyzed within chiral quark models with nonlocal separable interactions. For the case of two light flavors, we describe in detail the characteristics of the chiral phase transition in the T-mu plane, and analyze the color superconducting ... More
Main phenomenological features of the spontaneous CP violation in SU(3) x U(1) modelsMar 29 1996We analyze the phenomenological consequences of assuming spontaneous CP violation in an SU(3) x U(1) model with three Higgs triplets and one sextuplet. After the identification of the relevant physical scalars, we estimate the contributions to the parameters ... More
On the integrability of N=2 supersymmetric massive theoriesDec 03 1993Dec 09 1993In this paper we propose a criteria to establish the integrability of N=2 supersymmetric massive theories.The basic data required are the vacua and the spectrum of Bogomolnyi solitons, which can be neatly encoded in a graph (nodes=vacua and links= Bogomolnyi ... More
Non-Critical Confining Strings and the Renormalization GroupFeb 01 1999Mar 01 1999String vacua for non critical strings satisfying the requirements of Zig-Zag invariance are constructed. The Liouville mode is shown to play the r\^ole of scale in the Renormalization Group operation. Differences and similarities with the D-brane near ... More
Finding the Exact Delay Bound for Consensus of Linear Multi-Agent SystemsOct 22 2014This paper focuses on consensus problems for high-order, linear multi-agent systems. Undirected communication topologies and fixed, uniform communication time delay are taken into account. This class of problems has been widely study in the literature, ... More
Asymptotic dynamics, large gauge transformations and infrared symmetriesAug 19 2016Infrared finite S matrices enjoy an infinite family of symmetries, namely decoupling of asymptotic soft modes with arbitrary direction. The infrared structure of the theory manifests itself in the form of vacuum degeneracy and in nontrivial asymptotic ... More
A simple strobe to study high-order harmonics and multifrequency oscillations in mechanical resonatorsNov 02 2012A simple strobe setup with potential to study higher-order eigenmodes and multifrequency oscillations in micromechanical resonators is described. It requires standard equipment, commonly found in many laboratories, and it can thus be employed for public ... More
Auditory power-law activation-avalanches exhibit a fundamental computational ground-stateMar 15 2016The cochlea provides a biological information-processing paradigm that we only begin to under- stand in its full complexity. Our work reveals an interacting network of strongly nonlinear dynami- cal nodes, on which even simple sound input triggers subnetworks ... More