Results for "Albert Mas"

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Dirac operators, shell interactions and discontinuous gauge functions across the boundaryDec 11 2015Given a bounded smooth domain $\Omega\subset\mathbb{R}^3$, we explore the relation between couplings of the free Dirac operator $-i\alpha\cdot\nabla+m\beta$ with pure electrostatic shell potentials $\lambda\delta_{\partial\Omega}$ ($\lambda\in\mathbb{R}$) ... More
Discrepancy of minimal Riesz energy pointsJul 10 2019We find upper bounds for the spherical cap discrepancy of the set of minimizers of the Riesz $s$-energy on the sphere $\mathbb S^d.$ Our results are based in bounds for a Sobolev discrepancy introduced by Thomas Wolff in an unpublished manuscript where ... More
Variation and oscillation for singular integrals with odd kernel on Lipschitz graphsJan 10 2011Sep 02 2011We prove that, for r>2, the r-variation and oscillation for the smooth truncations of the Cauchy transform on Lipschitz graphs are bounded in L^p for 1<p finite. The analogous result holds for the n-dimensional Riesz transform on n-dimensional Lipschitz ... More
Klein's Paradox and the Relativistic $δ$-shell Interaction in $\mathbb{R}^3$Nov 28 2016Under certain hypothesis of smallness of the regular potential $\mathbf{V}$, we prove that the Dirac operator in $\mathbb{R}^3$ coupled with a suitable re-scaling of $\mathbf{V}$ converges in the strong resolvent sense to the Hamiltonian coupled with ... More
A dual characterization of the C^1 harmonic capacity and applicationsMar 20 2009Oct 09 2010The Lipschitz and C^1 harmonic capacities K and K_c in R^n can be considered as high-dimensional versions of the so-called analytic and continuous analytic capacities G and A (respectively). In this paper we provide a dual characterization of K_c in the ... More
Characterization of balls as minimizers of an endpoint Gagliardo seminorm on the boundaryMay 09 2018Given a bounded $C^2$ domain $\Omega\subset{\mathbb R}^d$ with $d\geq3$, we prove a sharp inequality which relates the perimeter of ${\partial\Omega}$ to the endpoint Gagliardo seminorm in $W^{r,2}({\partial\Omega})$, corresponding to $r=0$, of the normal ... More
Variation for singular integrals on Lipschitz graphs: L^p and endpoint estimatesOct 04 2011Let 0<n<d be integers and let H denote the n-dimensional Hausdorff measure restricted to an n-dimensional Lipschitz graph in R^d with slope strictly less than 1. For r>2, we prove that the r-variation and oscillation for Calder\'on-Zygmund singular integrals ... More
Failure of rational approximation on some Cantor type setsFeb 17 2019Let $A(K)$ be the algebra of continuous functions on a compact set $K\subset\mathbb C$ which are analytic on the interior of $K$, and $R(K)$ the closure (with the uniform convergence on $K$) of the functions that are analytic on a neighborhood of $K$. ... More
High-energy emission of variable objects in the OMC--VAR catalogueFeb 27 2013OMC-VAR is the first catalogue of variable sources observed by the Optical Monitoring Camera (OMC) on board INTEGRAL. It includes photometry and variability data for more than 5000 sources of very different nature. In order to study the multi-wavelength ... More
The MIT Bag Model as an infinite mass limitAug 29 2018The Dirac operator, acting in three dimensions, is considered. Assuming that a large mass $m>0$ lies outside a smooth and bounded open set $\Omega\subset\R^3$, it is proved that its spectrum is approximated by the one of the Dirac operator on $\Omega$ ... More
Lp-estimates for the variation for singular integrals on uniformly rectifiable setsApr 27 2015May 14 2016The $L^p$ ($1<p<\infty$) and weak-$L^1$ estimates for the variation for Calder\'on-Zygmund operators with smooth odd kernel on uniformly rectifiable measures are proven. The $L^2$ boundedness and the corona decomposition method are two key ingredients ... More
Variation for the Riesz transform and uniform rectifiabilitySep 02 2011For 0<n<d integers and r>2, we prove that an n-dimensional Ahlfors-David regular measure M in R^d is uniformly n-rectifiable if and only if the r-variation for the Riesz transform with respect to M is a bounded operator in L^2(M). This result can be considered ... More
The relativistic spherical $δ$-shell interaction in $\mathbb{R}^3$: spectrum and approximationApr 25 2017Nov 03 2017This note revolves on the free Dirac operator in $\mathbb{R}^3$ and its $\delta$-shell interaction with electrostatic potentials supported on a sphere. On one hand, we characterize the eigenstates of those couplings by finding sharp constants and minimizers ... More
Vapor-liquid-solid growth of serrated GaN nanowires: Shape selection driven by kinetic frustrationMay 16 2013Compound semiconducting nanowires are promising building blocks for several nanoelectronic devices yet the inability to reliably control their growth morphology is a major challenge. Here, we report the Au-catalyzed vapor-liquid-solid (VLS) growth of ... More
On the total absolute curvature of sphere eversionsMar 22 2005Oct 04 2005This paper has been withdrawn by the author, due to an error in Proposition 2.2.
Bayesian Estimates of the Large-Scale Velocity Field in Real Space and Redshift SpaceOct 04 1993Methods for inferring the velocity field from the peculiar velocity data are described and applied to old and newer data. Inhomogeneous Malmquist bias and ways to avoid it are discussed and utilized. We infer that these biases are probably important in ... More
The CMBR SpectrumMay 22 1997A short review of the measured spectrum of the Cosmic Microwave Background Radiation (CMBR) and implications. Extensions of the Kompaneets equation and Sunyaev-Zel'dovich effect are given.
Gauge theories on noncommutative spacesNov 29 2000I review my results about noncommutative gauge theories and about the relation of these theories to M(atrix) theory following my lecture on ICMP 2000.
Symmetry transformations in Batalin-Vilkovisky formalismOct 19 1993This short note is closely related to Sen-Zwiebach paper on gauge transformations in Batalin-Vilkovisky theory (hep-th 9309027). We formulate some conditions of physical equivalence of solutions to the quantum master equation and use these conditions ... More
Planetary nebulae in 2014: A review of researchJun 17 2015Jun 29 2015Planetary nebulae had a double anniversary in 2014, 250 year since their discovery and 150 year since the correct spectroscopic identification. This paper gives an overview of planetary nebula research published in 2014. Topics include surveys, central ... More
TV-min and Greedy Pursuit for Constrained Joint Sparsity and Application to Inverse ScatteringMay 17 2012Dec 19 2012This paper proposes a general framework for compressed sensing of constrained joint sparsity (CJS) which includes total variation minimization (TV-min) as an example. TV- and 2-norm error bounds, independent of the ambient dimension, are derived for the ... More
Scale- free networks in cell biologyOct 28 2005A cell's behavior is a consequence of the complex interactions between its numerous constituents, such as DNA, RNA, proteins and small molecules. Cells use signaling pathways and regulatory mechanisms to coordinate multiple processes, allowing them to ... More
Statistics of the First Galois Cohomology Group: A Refinement of Malle's ConjectureJul 14 2019Malle proposed a conjecture for counting the number of $G$-extensions $L/K$ with discriminant bounded above by $X$, denoted $N(K,G;X)$, where $G$ is a fixed transitive subgroup $G\subset S_n$ and $X$ tends towards infinity. We introduce a refinement of ... More
Shell interactions for Dirac operatorsMar 11 2013May 23 2013The self-adjointness of $H+V$ is studied, where $H=-i\alpha\cdot\nabla +m\beta$ is the free Dirac operator in $\R^3$ and $V$ is a measure-valued potential. The potentials $V$ under consideration are given by singular measures with respect to the Lebesgue ... More
Invariant manifolds and the parameterization method in coupled energy harvesting piezoelectric oscillatorsSep 11 2016Oct 08 2016Energy harvesting systems based on oscillators aim to capture energy from mechanical oscillations and convert it into electrical energy. Widely extended are those based on piezoelectric materials, whose dynamics are Hamiltonian submitted to different ... More
Graded Unification: A Framework for Interactive ProcessingJun 05 1994An extension to classical unification, called {\em graded unification} is presented. It is capable of combining contradictory information. An interactive processing paradigm and parser based on this new operator are also presented.
Twitch Plays Pokemon, Machine Learns Twitch: Unsupervised Context-Aware Anomaly Detection for Identifying Trolls in Streaming DataFeb 17 2019With the increasing importance of online communities, discussion forums, and customer reviews, Internet "trolls" have proliferated thereby making it difficult for information seekers to find relevant and correct information. In this paper, we consider ... More
Geometric approach to quantum theoryJun 12 2019We formulate quantum theory taking as a starting point the cone of states.
Three remarks on Matula numbersMay 23 2013In SIAM Review 10, page 273, D. W. Matula described a bijection between N and the set of topological rooted trees; the number is called the Matula number of the rooted tree. The Gutman-Ivic-Matula (GIM) function g(n) computes the number of edges of the ... More
Local structures and local exchange interactions in doped magnetic materials of different dimensionalityOct 02 2015Defects intentionally introduced into magnetic materials often have a profound effect on the physical properties. Specifically tailored neutron spectroscopic experiments can provide detailed information on both the local exchange interactions and the ... More
Removable singularities for Hölder continuous quasiregular mappings in the planeApr 20 2006We give necessary conditions for a set E to be removable for Holder continuous quasiregular mappings in the plane. We also obtain some removability results for Holder continuous mappings of finite distortion.
Un théorème limite pour les covariances des spins dans le modèle de Sherrington--Kirkpatrick avec champ externeMar 27 2007On \'{e}tudie la covariance (pour la mesure de Gibbs) des spins en deux sites dans le cas d'un mod\`{e}le de Sherrington--Kirkpatrick avec champ externe; lorsque le nombre de sites du mod\`{e}le tend vers l'infini, une \'{e}valuation asymptotique des ... More
Shell interactions for Dirac operators: on the point spectrum and the confinementJan 07 2014Jul 15 2014Spectral properties and the confinement phenomenon for the coupling $H+V$ are studied, where $H=-i\alpha\cdot\nabla +m\beta$ is the free Dirac operator in $\mathcal{R}^3$ and $V$ is a measure-valued potential. The potentials $V$ under consideration are ... More
Dynamics of coupled piezoelectric energy harvestersSep 11 2016In this article we consider an energy harvesting device given by the coupling of two piezoelastic oscillators. We write the system as two coupled duffing equations (which model the mechanical part of the piezoelastic beams) plus a perturbation. The latter ... More
Universal Numerical Encoder and Profiler Reduces Computing's Memory Wall with Software, FPGA, and SoC ImplementationsMar 20 2013In the multicore era, the time to computational results is increasingly determined by how quickly operands are accessed by cores, rather than by the speed of computation per operand. From high-performance computing (HPC) to mobile application processors, ... More
Remarks on QFT in the Coordinate SpaceSep 06 2016Generators of the Poincar\'e group, for a free massive scalar field, are usually expressed in the momentum space. In this work we perform a transformation of these generators into the coordinate space. This (spatial)-position space is spanned by eigenvectors ... More
Compressive Spectral Estimation with Single-Snapshot ESPRIT: Stability and ResolutionJul 06 2016In this paper Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) is developed for spectral estimation with single-snapshot measurement. Stability and resolution analysis with performance guarantee for Single-Snapshot ESPRIT ... More
Absolute Uniqueness of Phase Retrieval with Random IlluminationOct 23 2011Jul 20 2012Random illumination is proposed to enforce absolute uniqueness and resolve all types of ambiguity, trivial or nontrivial, from phase retrieval. Almost sure irreducibility is proved for any complex-valued object of a full rank support. While the new irreducibility ... More
Time Reversal Communication in Multi-Path Fading Channels with PinholesSep 18 2005The paper presents an analysis of the time reversal in multi-path Rayleigh-fading channels with $N$ inputs (transmitters) and $M$ outputs (receivers). The main issues addressed are the condition of statistical stability, the rate of information transfer ... More
Adaptive methods for PDE's: wavelets or mesh refinement?Dec 01 2002Adaptive mesh refinement techniques are nowadays an established and powerful tool for the numerical discretization of PDE's. In recent years, wavelet bases have been proposed as an alternative to these techniques. The main motivation for the use of such ... More
From Tarski to Gödel. Or, how to derive the Second Incompleteness Theorem from the Undefinability of Truth without Self-referenceMar 11 2018In this paper, we provide a fairly general self-reference-free proof of the Second Incompleteness Theorem from Tarski's Theorem of the Undefinability of Truth.
An isoperimetric-type inequality for electrostatic shell interactions for Dirac operatorsApr 16 2015In this article we investigate spectral properties of the coupling $H+V_\lambda$, where $H=-i\alpha\cdot\nabla +m\beta$ is the free Dirac operator in $\mathbb R^3$, $m>0$ and $V_\lambda$ is an electrostatic shell potential (which depends on a parameter ... More
Error and attack tolerance of complex networksAug 03 2000Many complex systems, such as communication networks, display a surprising degree of robustness: while key components regularly malfunction, local failures rarely lead to the loss of the global information-carrying ability of the network. The stability ... More
Mean-field theory for scale-free random networksJul 05 1999Random networks with complex topology are common in Nature, describing systems as diverse as the world wide web or social and business networks. Recently, it has been demonstrated that most large networks for which topological information is available ... More
The diameter of the world wide webJul 02 1999Sep 10 1999Despite its increasing role in communication, the world wide web remains the least controlled medium: any individual or institution can create websites with unrestricted number of documents and links. While great efforts are made to map and characterize ... More
Pointwise monotonicity of heat kernelsJul 29 2018May 25 2019In this paper the authors present a proof of a pointwise radial monotonicity property of heat kernels that is shared by the euclidean spaces, spheres and hyperbolic spaces. The main result deals with monotonicity from special points on revolution hypersurfaces ... More
A Teflon-based system for applying multidirectional voltages to lipid bilayers as a novel platform for membrane proteinsJul 12 2019Artificial bilayer lipid membranes (BLMs), along with patch-clamped membranes, are frequently used for functional analyses of membrane proteins. In both methods, the electric properties of membranes are characterized by only one parameter, namely, transmembrane ... More
Knowledge-Defined NetworkingJun 20 2016Jun 23 2016The research community has considered in the past the application of Artificial Intelligence (AI) techniques to control and operate networks. A notable example is the Knowledge Plane proposed by D.Clark et al. However, such techniques have not been extensively ... More
Pointwise monotonicity of heat kernelsJul 29 2018In this paper the authors present a proof of a pointwise radial monotonicity property of heat kernels that is shared by the euclidean spaces, spheres and hyperbolic spaces. The main result deals with monotonicity from special points on revolution hypersurfaces ... More
New Upper Bound for Sums of DilatesJul 17 2016For $\lambda \in \mathbb{Z}$, let $\lambda \cdot A = \{ \lambda a : a \in A\}$. We prove that if $|A+A| \le K |A|$ and $|\lambda_i| \le 2^r$ then \[ |\lambda_1 \cdot A + \ldots + \lambda_h \cdot A | \le K^{O((r+h)^2/\ln (r+h))} |A|. \] When $r$ and $h$ ... More
Quantization of classical curvesMar 05 2014Aug 18 2014We discuss the relation between quantum curves (defined as solutions of equation $[P,Q]=\hbar$, where $P,Q$ are ordinary differential operators) and classical curves. We illustrate this relation for the case of quantum curve that corresponds to the $(p,q)$-minimal ... More
Integrality theorems in the theory of topological stringsJul 10 2008Mar 12 2009We give a simplified derivation of the expression of instanton numbers and of mirror map in terms of Frobenius map on p-adic cohomology and use this expression to prove integrality theorems. Modifying this proof we verify that the Aganagic-Vafa formulas ... More
On Some Algebraic Structures Arising in String TheoryDec 11 1992Dec 18 1992Lian and Zuckerman proved that the homology of a topological chiral algebra can be equipped with the structure of a BV-algebra; \ie one can introduce a multiplication, an odd bracket, and an odd operator $\Delta$ having the same properties as the corresponding ... More
VLA Measurements of a sample of Planetary NebulaeMar 29 1994We report on new radio measurements of Galactic planetary nebulae, aimed at resolving the controversies on the reliability of older VLA flux densities and the suggested deviations from the standard Galactic extinction law found for planetary nebulae. ... More
Cohomological uniqueness, Massey products and the modular isomorphism problem for 2-groups of maximal nilpotency classMay 05 2011Nov 09 2011Let $G$ be a finite 2-group of maximal nilpotency class, and let $BG$ be its classifying space. We prove that iterated Massey products in $H^*(BG;\F_2)$ do characterize the homotopy type of $BG$ among 2-complete spaces with the same cohomological structure. ... More
Weighted estimates for Beltrami equationsDec 23 2011We obtain a priori estimates in $L^p(\omega)$ for the generalized Beltrami equation, provided that the coefficients are compactly supported $VMO$ functions with the expected ellipticity condition, and the weight $\omega$ lies in the Muckenhoupt class ... More
Counterexamples to quasiconcavity for the heat equationFeb 13 2018Jul 17 2018We construct solutions to the heat equation on convex rings showing that quasiconcavity may not be preserved along the flow, even for smooth and subharmonic initial data.
On a question of Krajewski'sDec 05 2017In this paper we provide a (negative) solution to a problem posed by Stanis{\l}aw Krajewski. Consider a recursively enumerable theory U and a finite expansion of the signature of U that contains at least one predicate symbol of arity $\ge$ 2. We show ... More
An Introduction to Hyperbolic Barycentric Coordinates and their ApplicationsMar 31 2013Barycentric coordinates are commonly used in Euclidean geometry. The adaptation of barycentric coordinates for use in hyperbolic geometry gives rise to hyperbolic barycentric coordinates, known as gyrobarycentric coordinates. The aim of this article is ... More
Uniquely-Wilf classesApr 11 2019Two permutations in a class are Wilf-equivalent if, for every size, $n$, the number of permutations in the class of size $n$ containing each of them is the same. Those infinite classes that have only one equivalence class in each size for this relation ... More
The $\Box_b$-heat equation on quadric manifoldsJul 01 2009In this article, we give an explicit calculation of the partial Fourier transform of the $\Box_b$-heat equation on quadric submanifolds of $M\subset C^n\times C^m$. As a consequence, we can also compute the heat kernel associated to the weighted dbar-equation ... More
A Simplified Calculation for the Fundamental Solution to the Heat Equation on the Heisenberg GroupNov 26 2007Let $L = -1/4 (\sum_{j=1}^n(X_j^2+Y_j^2)+i\gamma T)$ where $\gamma$ is a complex number, $X_j$, $Y_j$, and $T$ are the left invariant vector fields of the Heisenberg group structure for $R^n \times R^n \times R$. We explicitly compute the Fourier transform ... More
Space-frequency correlation of classical waves in disordered media: high-frequency and small scale asymptoticsJun 25 2007Two-frequency radiative transfer (2f-RT) theory is developed for geometrical optics in random media. The space-frequency correlation is described by the two-frequency Wigner distribution (2f-WD) which satisfies a closed form equation, the two-frequency ... More
Self-Averaging Scaling Limits of Two-Frequency Wigner Distribution for Random Paraxial WavesSep 23 2006Apr 24 2007Two-frequency Wigner distribution is introduced to capture the asymptotic behavior of the space-frequency correlation of paraxial waves in the radiative transfer limits. The scaling limits give rises to deterministic transport-like equations. Depending ... More
The MUSIC Algorithm for Sparse Objects: A Compressed Sensing AnalysisJun 09 2010Nov 09 2010The MUSIC algorithm, with its extension for imaging sparse {\em extended} objects, is analyzed by compressed sensing (CS) techniques. The notion of restricted isometry property (RIP) and an upper bound on the restricted isometry constant (RIC) are employed ... More
Compressive Inverse Scattering II. SISO Measurements with Born scatterersAug 27 2009Jan 05 2010Inverse scattering methods capable of compressive imaging are proposed and analyzed. The methods employ randomly and repeatedly (multiple-shot) the single-input-single-output (SISO) measurements in which the probe frequencies, the incident and the sampling ... More
Limit Theorems for Motions in a Flow with a Nonzero DriftJul 27 1999We establish diffusion and fractional Brownian motion approximations for motions in a Markovian Gaussian random field with a nonzero mean.
Rateless Lossy Compression via the ExtremesJun 25 2014Mar 08 2016We begin by presenting a simple lossy compressor operating at near-zero rate: The encoder merely describes the indices of the few maximal source components, while the decoder's reconstruction is a natural estimate of the source components based on this ... More
Binary central stars of planetary nebulaeOct 18 2006This paper reviews our knowledge on binary central stars of planetary nebulae and presents some personal opinions regarding their evolution. Three types of interactions are distinguished: type I, where the binary companion induces the mass loss; type ... More
Low-mass supernovae in the early Galactic halo: source of the double r/s-process enriched halo stars?Dec 18 2003Several stars at the low-metallicity extreme of the Galactic halo ([Fe/H]=-2.5) show strong enhancements of both s-process and r-process elements. The presence of s-process elements in main-sequence stars is explained via mass transfer from an AGB companion ... More
Hydrogen-poor planetary nebulaeMay 25 2001Five planetary nebulae are known to show hydrogen-poor material near the central star. In the case of A58, this gas was ejected following a late thermal pulse similar to Sakurai's Object. In this paper I will review these five objects. One of them, IRAS ... More
Stellar Evolution and Mass Loss on the Asymptotic Giant BranchNov 07 1994Mass loss dominates the stellar evolution on the Asymptotic Giant Branch. The phase of highest mass-loss occurs during the last 1--10\% of the AGB and includes the so-called Miras and OH/IR stars. In this review I will discuss the characteristics and ... More
Helical, Angular and Radial Ordering in Narrow CapillariesApr 27 2007To enlighten the nature of the order-disorder and order-order transitions in block copolymer melts confined in narrow capillaries we analyze peculiarities of the conventional Landau weak crystallization theory of systems confined to cylindrical geometry. ... More
Systematic search for VHE gamma-ray emission from X-ray bright high-frequency BL Lac objectsJun 29 2007Dec 21 2007All but three (M87, BL Lac and 3C 279) extragalactic sources detected so far at very high energy (VHE) gamma-rays belong to the class of high-frequency peaked BL Lac (HBL) objects. This suggested to us a systematic scan of candidate sources with the MAGIC ... More
Confirmation of the Copernican principle at Gpc radial scale and above from the kinetic Sunyaev Zel'dovich effect power spectrumSep 20 2010Jun 24 2011The Copernican principle, a cornerstone of modern cosmology, remains largely unproven at Gpc radial scale and above. Here we will show that, violations of this type will inevitably cause a first order anisotropic kinetic Sunyaev Zel'dovich (kSZ) effect. ... More
Minimum degree thresholds for bipartite graph tilingOct 16 2014For any bipartite graph $H$, we determine a minimum degree threshold for a balanced bipartite graph $G$ to contain a perfect $H$-tiling. We show that this threshold is best possible up to a constant depending only on $H$. Additionally, we prove a corresponding ... More
Global approximation of CR functions on Bloom-Graham model graphs in $C^n$Sep 08 2004We define a class of generic CR submanifolds of $C^n$ of real codimension $d$, with $d$ in $1, ..., n-1$, called the Bloom-Graham model graphs, whose graphing functions are partially decoupled in their dependence on the variables in the real directions. ... More
Lewisian Fixed Points I: Two Incomparable ConstructionsMay 23 2019Our paper is the first study of what one might call "reverse mathematics of explicit fixpoints". We study two methods of constructing such fixpoints for formulas whose principal connective is the intuitionistic Lewis arrow. Our main motivation comes from ... More
Kolmogorov widths under holomorphic mappingsFeb 24 2015If $L$ is a bounded linear operator mapping the Banach space $X$ into the Banach space $Y$ and $K$ is a compact set in $X$, then the Kolmogorov widths of the image $L(K)$ do not exceed those of $K$ multiplied by the norm of $L$. We extend this result ... More
Prolific CompositionsApr 11 2019Under what circumstances might every extension of a combinatorial structure contain more copies of another one than the original did? This property, which we call prolificity, holds universally in some cases (e.g., finite linear orders) and only trivially ... More
Fundamental Solutions to $\Box_b$ on Certain QuadricsOct 26 2011The purpose of this article is to expand the number of examples for which the complex Green operator, that is, the fundamental solution to the Kohn Laplacian, can be computed. We use the Lie group structure of quadric submanifolds of $\mathbb C^n\times\mathbb ... More
On the length of the longest subsequence avoiding an arbitrary pattern in a random permutationMay 23 2005May 31 2005We consider the distribution of the length of the longest subsequence avoiding a given pattern in a random permutation of length n. The well-studied case of a longest increasing subsequence corresponds to avoiding the pattern 21. We show that there is ... More
Information gain in quantum continual measurementsDec 01 2006Inspired by works on information transmission through quantum channels, we propose the use of a couple of mutual entropies to quantify the efficiency of continual measurement schemes in extracting information on the measured quantum system. Properties ... More
Pulsation-triggered mass loss from AGB stars: the 60-day critical periodMay 09 2016Low- and intermediate-mass stars eject much of their mass during the late, red giant branch (RGB) phase of evolution. The physics of their strong stellar winds is still poorly understood. In the standard model, stellar pulsations extend the atmosphere, ... More
V_ud and V_us: CKM 2010 working group I summaryDec 01 2011The present status of universality tests of the weak couplings for quarks and leptons is reviewed, with updated information for the muon lifetime and for first-row inputs in the CKM matrix. We discuss the impact of this high-precision SM test in constraining ... More
Gauge Structures: From Stabilizer Codes to Continuum ModelsSep 26 2018Feb 09 2019Stabilizer codes are a powerful method for implementing fault-tolerant quantum memory and in the case of topological codes, they form useful models for topological phases of matter. In this paper, we discuss the theory of stabilizer codes as a discrete ... More
Firing-rate, symbolic dynamics and frequency dependence in periodically driven spiking models: a piecewise-smooth approachOct 04 2013Apr 04 2014In this work we consider a periodically forced generic integrate-and-fire model with a unique attracting equilibrium in the subthreshold dynamics and study the dependence of the firing-rate on the frequency of the drive. In an earlier study we have obtained ... More
Additive Polynomials for Finite Groups of Lie TypeJun 07 2009Feb 03 2010This paper provides a realization of all classical and most exceptional finite groups of Lie type as Galois groups over function fields over F_q and derives explicit additive polynomials for the extensions. Our unified approach is based on results of ... More
Reduced fusion systems over $p$-groups with abelian subgroup of index $p$: IIIAug 29 2017Dec 14 2017We finish the classification, begun in two earlier papers, of all simple fusion systems over finite nonabelian $p$-groups with an abelian subgroup of index $p$. In particular, this gives many new examples illustrating the enormous variety of exotic examples ... More
Magnetic Cluster ExcitationsNov 20 2012Magnetic clusters, i.e., assemblies of a finite number (between two or three and several hundred) of interacting spin centers which are magnetically decoupled from their environment, can be found in many materials ranging from inorganic compounds, magnetic ... More
Metabolic and Chaperone Gene Loss Marks the Origin of Animals: Evidence for Hsp104 and Hsp78 Sharing Mitochondrial ClientsJan 15 2013Feb 28 2015The evolution of animals involved acquisition of an emergent gene repertoire for gastrulation. Whether loss of genes also co-evolved with this developmental reprogramming has not yet been addressed. Here, we identify twenty-four genetic functions that ... More
Non-Singular Cosmology and Gauge Theories of GravitationJun 08 2004The resolution of the problem of cosmological singularity in the framework of gauge theories of gravitation is discussed. Generalized cosmological Friedmann equations for homogeneous isotropic models filled by interacting scalar fields and usual gravitating ... More
Observation of VHE Gamma Radiation from HESS J1834-087/W41 with the MAGIC TelescopeApr 10 2006Recently, the HESS array has reported the detection of gamma-ray emission above a few hundred GeV from eight new sources located close to the Galactic Plane. The source HESS J1834-087 is spatially coincident with SNR G23.3-0.3 (W41). Here we present MAGIC ... More
Structure-dynamics relation in shaken optical latticesMay 28 2015Shaken optical lattices permit to coherently modify the tunneling of particles in a controllable manner. We introduce a general relation between the geometry of shaken lattices and their admissible effective dynamics. Using three different examples, we ... More
Existence and stability of a two-parameter family of solitary waves for an NLS-KdV systemDec 17 2012We prove existence and stability results for a two-parameter family of solitary-wave solutions to a system in which an equation of nonlinear Schr\"odinger type is coupled to an equation of Korteweg-de Vries type. Such systems model interactions between ... More
The standard coder: a machine learning approach to measuring the effort required to produce source code changeMar 06 2019We apply machine learning to version control data to measure the quantity of effort required to produce source code changes. We construct a model of a `standard coder' trained from examples of code changes produced by actual software developers together ... More
Heat Kernels, Smoothness Estimates and Exponential DecayApr 01 2010In this article, we establish Gaussian decay for the Box_b-heat kernel on polynomial models in C^2. Our technique attains the exponential decay via a partial Fourier transform. On the transform side, the problem becomes finding quantitative smoothness ... More
Weak KAM theorem on non compact manifoldsFeb 22 2015In this paper, we consider a time independent $C^2$ Hamiltonian, sa\-tisfying the usual hypothesis of the classical Calculus of Variations, on a non-compact connected manifold. Using the Lax-Oleinik semigroup, we give a proof of the existence of weak ... More
Kolmogorov widths and low-rank approximations of parametric elliptic PDEsFeb 10 2015Kolmogorov $n$-widths and low-rank approximations are studied for families of elliptic diffusion PDEs parametrized by the diffusion coefficients. The decay of the $n$-widths can be controlled by that of the error achieved by best $n$-term approximations ... More
Nested critical points for a directed polymer on a disordered diamond latticeFeb 22 2016Sep 28 2017We consider a model for a directed polymer in a random environment defined on a hierarchical diamond lattice in which i.i.d. random variables are attached to the lattice bonds. Our focus is on scaling schemes in which a size parameter $n$, counting the ... More