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Ohmic contact engineering in few-layer black Phosphorus field effect transistorsMay 14 2019Achieving good quality Ohmic contacts to van der Waals materials is a challenge, since at the interface between metal and van der Waals material, different conditions can occur, ranging from the presence of a large energy barrier between the two materials ... More

Decoration of exfoliated black phosphorus with nickel nanoparticles and application in catalysisSep 16 2016Aug 28 2017Nickel nanoparticles were dispersed on the surface of exfoliated black phosphorus and the resulting nanohybrid Ni/2DBP showed an improved stability respect to pristine 2D BP when kept in ambient conditions in the darkness. Ni/2DBP was applied as catalyst ... More

Novel polystyrene-based nanocomposites by phosphorene dispersionFeb 14 2017Polystyrene-based phosphorene nanocomposites were prepared by a solvent blending procedure allowing the embedding of black phosphorus (BP) nanoflakes in the polymer matrix. Raman spectroscopy, X Ray Diffraction and TEM microscopy were employed to characterize ... More

Reconstruction of the singularities of a potential from backscattering data in 2D and 3DFeb 18 2009We prove that the singularities of a potential in the two and three dimensional Schr\"odinger equation are the same as the singularities of the Born approximation (Diffraction Tomography), obtained from backscattering inverse data, with an accuracy of ... More

Large spin-mixing conductance in highly Bi-doped Cu thin filmsJun 04 2018Jul 24 2018Spin Hall effect provides an efficient tool for the conversion of a charge current into a spin current, opening the possibility of producing pure spin currents in non-magnetic materials for the next generation of spintronics devices. In this sense, giant ... More

Black Phosphorus/Palladium Nanohybrid: Unraveling the Nature of P-Pd Interaction and Application in Selective HydrogenationMar 06 2019The burgeoning interest in 2D black phosphorus (bP) contributes to expand its applications in countless fields. In the present study, 2D bP is used as a support for homogeneously dispersed palladium nanoparticles directly grown on it by a wet chemical ... More

Non-Classical Longitudinal Magneto-Resistance in Anisotropic Black PhosphorusAug 02 2018Dec 05 2018Resistivity measurements of a few-layer black phosphorus (bP) crystal in parallel magnetic fields up to 45 T are reported as a function of the angle between the in-plane field and the source-drain (S-D) axis of the device. The crystallographic directions ... More

A Perspective on Recent Advances in Phosphorene Functionalization and its Application in DevicesMar 28 2019Phosphorene, the 2D material derived from black phosphorus, has recently attracted a lot of interest for its properties, suitable for applications in material science. In particular, the physical features and the prominent chemical reactivity on its surface ... More

Chiral Corrections to Baryon Electromagnetic Form FactorsMar 03 2017Corrections motivated by chiral symmetry arguments have long been known to give important contributions to hadronic observables, particularly at low momentum transfer. It is possible to separate these approaches into two broad groups; either the corrections ... More

Relative equilibria in continuous stellar dynamicsJan 27 2010We study a three dimensional continuous model of gravitating matter rotating at constant angular velocity. In the rotating reference frame, by a finite dimensional reduction, we prove the existence of non radial stationary solutions whose supports are ... More

The Chemical Composition of the Small Magellanic Cloud H II Region NGC 346 and the Primordial Helium AbundanceMar 10 2000Jul 20 2000Spectrophotometry in the 3400-7400 range is presented for 13 areas of the brightest H II region in the SMC: NGC 346. The observations were obtained at CTIO with the 4-m telescope. Based on these observations its chemical composition is derived. The helium ... More

Group rings with Lie metabelian set of symmetric elementsOct 30 2013Let $R$ be a commutative ring of characteristic zero and $G$ an arbitrary group. In the present paper we classify the groups $G$ for which the set of symmetric elements with respect to the classical involution of the group ring $RG$ is Lie metabelian. ... More

Escape of photons from two fixed extreme Reissner-Nordström black holesJan 09 2007Nov 20 2008We study the scattering of light (null geodesics) by two fixed extreme Reissner-Nordstr\"om black holes, in which the gravitational attraction of their masses is exactly balanced with the electrostatic repulsion of their charges, allowing a static spacetime. ... More

Chemical Composition of Two H II Regions in NGC 6822 Based on VLT SpectroscopyJul 04 2005We present long slit spectrophotometry of regions V and X of the local group irregular galaxy NGC 6822. The data consist of VLT FORS observations in the 3450 to 7500 A range. We have obtained electron temperatures and densities using different line intensity ... More

Inference of stochastic parameterizations for model error treatment using nested ensemble Kalman filtersJul 27 2018Stochastic parameterizations are increasingly being used to represent the uncertainty associated with model errors in ensemble forecasting and data assimilation. One of the challenges associated with the use of these parameterizations is the optimization ... More

Seven problems related to the determination of the primordial helium abundanceNov 22 2002Recent advances on the quest to determine the primordial or pregalactic helium abundance, Yp, are reviewed. There are seven problems affecting the He/H abundance determinations of H II regions that are briefly discussed: the underlying absorption lines ... More

Indices of the iterates of $R^3$-homeomorphisms at Lyapunov stable fixed pointsApr 18 2007Given any positive sequence (\{c_n\}_{n \in {\Bbb N}}), we construct orientation preserving homeomorphisms (f:{\Bbb R}^3 \to {\Bbb R}^3) such that (Fix(f)=Per(f)=\{0\}), (0) is Lyapunov stable and (\limsup \frac{|i(f^m, 0)|}{c_m}= \infty). We will use ... More

Baryon Octet Electromagnetic Form Factors in a confining NJL modelMar 08 2016Electromagnetic form factors of the baryon octet are studied using a Nambu--Jona-Lasinio model which utilizes the proper-time regularization scheme to simulate aspects of colour confinement. In addition, the model also incorporates corrections to the ... More

Rho meson form factors in a confining Nambu--Jona-Lasinio modelApr 30 2015Elastic electromagnetic form factors for the $\rho^+$ meson are calculated in a Nambu--Jona-Lasinio model which incorporates quark confinement through the use of the proper-time regularization scheme. A comparison is made with recent lattice QCD results ... More

Markov chain approach to anomalous diffusion on Newman-Watts networksJan 31 2019Feb 26 2019A Markov chain (MC) formalism is used to investigate the mean-square displacement (MSD) of a random walker on Newman-Watts (NW) networks. It leads to a precise analysis of the conditions for the emergence of anomalous sub- or super-diffusive regimes in ... More

Groups of units of integral group rings commensurable with direct products of free-by-free groupsNov 18 2005Oct 17 2006We classify the finite groups $G$ such that the group of units of the integral group ring ${\mathbb Z} G$ has a subgroup of finite index which is a direct product of free-by-free groups.

DADA: Data Assimilation for the Detection and Attribution of Weather- and Climate-related EventsMar 17 2015We describe a new approach allowing for systematic causal attribution of weather and climate-related events, in near-real time. The method is purposely designed to facilitate its implementation at meteorological centers by relying on data treatments that ... More

Modeling analysis and optimization for European network data mergingJul 08 2016In this paper, the problem of building a consistent European network state based on the data provided by different Transmission System Operators (TSOs) is addressed. A hierarchical merging procedure is introduced and consists in the resolution of several ... More

A Julia Module for Polynomial Optimization with Complex Variables applied to Optimal Power FlowApr 18 2019Many optimization problems in power transmission networks can be formulated as polynomial problems with complex variables. A polynomial optimization problem with complex variables consists in optimizing a real-valued polynomial whose variables and coefficients ... More

Why many theories of shock waves are necessary. Convergence error in formally path-consistent schemesAug 14 2008We are interested in nonlinear hyperbolic systems in nonconservative form arising in fluid dynamics, and, for solutions containing shock waves, we investigate the convergence of finite difference schemes applied to such systems. According to Dal Maso, ... More

Dephasing in strongly anisotropic black phosphorusJul 29 2016Aug 15 2016Weak localization was observed and determined in a black phosphorus (bP) field-effect transistor 65 nm thick. The weak localization behaviour was found to be in excellent agreement with the Hikami-Larkin-Nagaoka model for fields up to 1~T, from which ... More

Early Science with the Large Millimetre Telescope: Fragmentation of molecular clumps in the GalaxySep 26 2017Sensitive, imaging observations of the 1.1 mm dust continuum emission from a 1 deg^2 area collected with the AzTEC bolometer camera on the Large Millimeter Telescope are presented. A catalog of 1545 compact sources is constructed based on a Wiener-optimization ... More

Phosphorus oxide gate dielectric for black phosphorus field effect transistorsApr 10 2018The environmental stability of the layered semiconductor black phosphorus (bP) remains a challenge. Passivation of the bP surface with phosphorus oxide, POx, grown by a reactive ion etch with oxygen plasma is known to improve photoluminescence efficiency ... More

Calculo Estocastico, EDEs y EDPsApr 13 2015This manuscript is a self-contained overview of essential results of stochastic calculus and stochastic differential equations, and their connection with final-value problems for second order linear PDEs.

On the LP formulation in measure spaces of optimal control problems for jump-diffusionsApr 14 2015In this short note we formulate a infinite-horizon stochastic optimal control problem for jump-diffusions of Ito-Levy type as a LP problem in a measure space, and prove that the optimal value functions of both problems coincide. The main tools are the ... More

Intersection cuts for factorable MINLPDec 07 2018Given a factorable function f, we propose a procedure that constructs a concave underestimator of f that is tight at a given point. These underestimators can be used to generate intersection cuts. A peculiarity of these underestimators is that they do ... More

A note on space-time Holder regularity of mild solutions to stochastic Cauchy problems in Lp-spacesMay 01 2014This paper revisits the H\"{o}lder regularity of mild solutions of parabolic stochastic Cauchy problems in Lebesgue spaces $L^p(\mathcal{O}),$ with $p\geq 2$ and $\mathcal{O}\subset\mathbb{R}^d$ a bounded domain. We find conditions on $p, \beta$ and $\gamma$ ... More

Backward Ornstein-Uhlenbeck transition operators and mild solutions of non-autonomous Hamilton-Jacobi equations in Banach spacesOct 03 2014In this paper we revisit the mild-solution approach to second-order semi-linear PDEs of Hamilton-Jacobi type in infinite-dimensional spaces. We show that a well-known result on existence of mild solutions in Hilbert spaces can be easily extended to non-autonomous ... More

Noise-enhanced chaos in a weakly coupled GaAs/(Al,Ga)As superlatticeJan 10 2017Jan 11 2017Noise-enhanced chaos in a doped, weakly coupled GaAs/Al_{0.45}Ga_{0.55}As superlattice has been observed at room temperature in experiments as well as in the results of the simulation of nonlinear transport based on a discrete tunneling model. When external ... More

Comprehensive classification of the plant non-specific lipid transfer protein superfamily towards its Sequence -Structure -Function analysisMay 02 2019Background. Non-specific Lipid Transfer Proteins (nsLTPs) are widely distributed in the plant kingdom and constitute a superfamily of related proteins. More than 800 different sequences have been characterized so far, but their biological functions remain ... More

The role of water in the preparation and stabilization of high quality phosphorene flakesNov 13 2015Water is believed to be harmful for the stability of phosphorene.On the contrary, the presence of small amount of water allows the synthesis of high-quality material in liquid exfoliation of black phosphorus using dimethylsulfoxide as solvent. A phosphorus/water ... More

Hybrid 2D Black Phosphorus/Polymer Materials: New Platforms for Device FabricationFeb 04 2018Hybrid materials, containing a 2D filler embedded in a polymeric matrix, are an interesting platform for several applications, because of the variety of properties that the filler can impart to the polymer matrix when dispersed at the nanoscale. Moreover, ... More

Hop and HipHop : Multitier Web OrchestrationNov 30 2013Rich applications merge classical computing, client-server concurrency, web-based interfaces, and the complex time- and event-based reactive programming found in embedded systems. To handle them, we extend the Hop web programming platform by HipHop, a ... More

Early Science with the Large Millimetre Telescope: Molecules in the Extreme Outflow of a proto-Planetary NebulaJan 04 2017Extremely high velocity emission likely related to jets is known to occur in some proto-Planetary Nebulae. However, the molecular complexity of this kinematic component is largely unknown. We observed the known extreme outflow from the proto-Planetary ... More

The Role of Oligomeric Gold-Thiolate Units in Single Molecule Junc-tions of Thiol-Anchored MoleculesMar 20 2018Using the break junction (BJ) technique we show that Au(RS)2 units play a significant role in thiol-terminated molecular junctions formed on gold. We have studied a range of thiol-terminated compounds, either with the sulfur atoms in direct conjugation ... More

Noncovalent functionalization of few-layer black phosphorus with metal nanoparticles and its application in catalysisSep 16 2016Transition metal nanoparticles of Ni, Pd, Ru and Au, each of them stabilized by a suitable capping agent, were dispersed on the surface of few-layer black phosphorus (2D BP) achieving new nanocomposite 2D materials. Ni nanoparticles supported on 2D BP ... More

Perturbative quantization of Yang-Mills theory with classical double as gauge algebraDec 07 2015Feb 22 2016Perturbative quantization of Yang-Mills theory with a gauge algebra given by the classical double of a semisimple Lie algebra is considered. The classical double of a real Lie algebra is a nonsemisimple real Lie algebra that admits a nonpositive definite ... More

Gauge-fixing independence of IR divergences in non-commutative U(1), perturbative tachyonic instabilities and supersymmetryDec 19 2000Jan 19 2001It is argued that the quadratic and linear non-commutative IR divergences that occur in U(1) theory on non-commutative Minkowski spacetime for small non-commutativity matrices $\theta^{\mu\nu}$ are gauge-fixing independent. This implies in particular ... More

IASIS and BigMedilytics: Towards personalized medicine in EuropeSep 20 2018One field of application of Big Data and Artificial Intelligence that is receiving increasing attention is the biomedical domain. The huge volume of data that is customary generated by hospitals and pharmaceutical companies all over the world could potentially ... More

UV/IR mixing and the Goldstone theorem in noncommutative field theoryFeb 01 2002May 27 2002Noncommutative IR singularities and UV/IR mixing in relation with the Goldstone theorem for complex scalar field theory are investigated. The classical model has two coupling constants, $\lambda_1$ and $\lambda_2$, associated to the two noncommutative ... More

Yang-Mills theory for semidirect products ${\rm G}\ltimes\mathfrak{g}^*$ and its instantonsAug 05 2014Jun 26 2015Yang-Mills theory with a symmetry algebra that is the semidirect product $\mathfrak{h}\ltimes\mathfrak{h}^*$ defined by the coadjoint action of a Lie algebra $\mathfrak{h}$ on its dual $\mathfrak{h}^*$ is studied. The gauge group is the semidirect product ... More

Utility maximization in pure-jump models driven by marked point processes and nonlinear wealth dynamicsNov 04 2014Sep 21 2015We explore martingale and convex duality techniques to study optimal investment strategies that maximize expected risk-averse utility from consumption and terminal wealth. We consider a market model with jumps driven by (multivariate) marked point processes ... More

The PAU Survey: Operation and orchestration of multi-band survey dataNov 06 2018The Physics of the Accelerating Universe (PAU) Survey is an international project for the study of cosmological parameters associated with Dark Energy. PAU's 18-CCD camera (PAUCam), installed at the prime focus of the William Herschel Telescope at the ... More

Maximal fillings of moon polyominoes, simplicial complexes, and Schubert polynomialsSep 23 2010Jul 05 2011We exhibit a canonical connection between maximal (0,1)-fillings of a moon polyomino avoiding north-east chains of a given length and reduced pipe dreams of a certain permutation. Following this approach we show that the simplicial complex of such maximal ... More

Optimal relaxed control of dissipative stochastic partial differential equations in Banach spacesJan 18 2010Mar 17 2010We study an optimal relaxed control problem for a class of semilinear stochastic PDEs on Banach spaces perturbed by multiplicative noise and driven by a cylindrical Wiener process. The state equation is controlled through the nonlinear part of the drift ... More

Optimal continuous-time ALM for insurers: a martingale approachOct 19 2018We study a continuous-time asset-allocation problem for a firm in the insurance industry that backs up the liabilities raised by the insurance contracts with the underwriting profits and the income resulting from investing in the financial market. Using ... More

Towards Proxemic Mobile Collocated InteractionsSep 06 2017Research on mobile collocated interactions has been exploring situations where collocated users engage in collaborative activities using their personal mobile devices (e.g., smartphones and tablets), thus going from personal/individual toward shared/multiuser ... More

Thermodynamically consistent mesoscopic fluid particle models for a van der Waals fluidFeb 02 2000The GENERIC structure allows for a unified treatment of different discrete models of hydrodynamics. We first propose a finite volume Lagrangian discretization of the continuum equations of hydrodynamics through the Voronoi tessellation. We then show that ... More

Computer-assisted proofs in PDE: a surveyOct 01 2018In this survey we present some recent results concerning computer-assisted proofs in partial differential equations, focusing in those coming from problems in incompressible fluids. Particular emphasis is put on the techniques, as opposed to the results ... More

Quasi-symmetric and non-commutative affine Schur functionsMay 10 2012We introduce dual Hopf algebras which simultaneously combine the concepts of the k-Schur function theory with the quasi-symmetric Schur function theory. We construct dual basis of these Hopf algebras with remarkable properties.

On the existence of stationary patchesJul 18 2018In this paper, we show the existence of a family of analytic stationary patch solutions of the SQG and gSQG equations. This answers an open problem in [F. de la Hoz, Z. Hassainia, T. Hmidi. Arch. Ration. Mech. Anal., 220(3):1209-1281, 2016].

Realization Spaces of Uniform Phased MatroidsJul 19 2018A phased matroid is a matroid with additional structure which plays the same role for complex vector arrangements that oriented matroids play for real vector arrangements. The realization space of an oriented (resp., phased) matroid is the space of vector ... More

A general cipher for individual data anonymizationDec 07 2017Over the years, the literature on individual data anonymization has burgeoned in many directions. Borrowing from several areas of other sciences, the current diversity of concepts, models and tools available contributes to understanding and fostering ... More

A multiplicative masking method for preserving the skewness of the original micro-recordsDec 07 2017Masking methods for the safe dissemination of microdata consist of distorting the original data while preserving a pre-defined set of statistical properties in the microdata. For continuous variables, available methodologies rely essentially on matrix ... More

Drived diffusion of vector fieldsMar 16 1998Oct 29 1998A model for the diffusion of vector fields driven by external forces is proposed. Using the renormalization group and the $\epsilon$-expansion, the dynamical critical properties of the model with gaussian noise for dimensions below the critical dimension ... More

Noncommutative Einstein-Maxwell pp-wavesJul 25 2006Oct 23 2006The field equations coupling a Seiberg-Witten electromagnetic field to noncommutative gravity, as described by a formal power series in the noncommutativity parameters $\theta^{\alpha\beta}$, is investigated. A large family of solutions, up to order one ... More

On some consequences of the permutation paradigm for data anonymization: centrality of permutation matrices, universal measures of disclosure risk and information loss, evaluation by dominanceJan 29 2017Recently, the permutation paradigm has been proposed in data anonymization to describe any micro data masking method as permutation, paving the way for performing meaningful analytical comparisons of methods, something that is difficult currently in statistical ... More

On the Schrodinger-Poisson-Slater system: behavior of minimizers, radial and nonradial casesApr 19 2009This paper is motivated by the study of a version of the so-called Schrodinger-Poisson-Slater problem: $$ - \Delta u + \omega u + \lambda (u^2 \star \frac{1}{|x|}) u=|u|^{p-2}u,$$ where $u \in H^1(\R^3)$. We are concerned mostly with $p \in (2,3)$. The ... More

Polymer-based black phosphorus (bP) hybrid materials by in situ radical polymerization: an effective tool to exfoliate bP and stabilize bP nanoflakesApr 11 2018Black phosphorus (bP) has been recently investigated for next generation nanoelectronic multifunctional devices. However, the intrinsic instability of exfoliated bP (the bP nanoflakes) towards both moisture and air has so far overshadowed its practical ... More

Geometric construction of D-branes in WZW modelsApr 25 2011Sep 02 2011The geometric description of D-branes in WZW models is pushed forward. Our starting point is a gluing condition\, $J_{+}=FJ_-$ that matches the model's chiral currents at the worldsheet boundary through a linear map $F$ acting on the WZW Lie algebra. ... More

Seiberg--Witten maps for $\boldsymbol{SO(1,3)}$ gauge invariance and deformations of gravityAug 14 2008Dec 12 2008A family of diffeomorphism-invariant Seiberg--Witten deformations of gravity is constructed. In a first step Seiberg--Witten maps for an SO(1,3) gauge symmetry are obtained for constant deformation parameters. This includes maps for the vierbein, the ... More

Quantization of the open string on plane-wave limits of dS_n x S^n and non-commutativity outside branesNov 19 2007Feb 25 2008The open string on the plane-wave limit of $dS_n\times S^n $ with constant $B_2$ and dilaton background fields is canonically quantized. This entails solving the classical equations of motion for the string, computing the symplectic form, and defining ... More

Entropy budget for Hawking evaporationJul 24 2017Blackbody radiation, emitted from a furnace and described by a Planck spectrum, contains (on average) an entropy of $3.9\pm 2.5$ bits per photon. Since normal physical burning is a unitary process, this amount of entropy is compensated by the same amount ... More

Navigable maps of structural brain networks across speciesJan 18 2018Brains are spatially embedded networks whose architecture has been shaped by physical and biochemical constraints throughout evolution. While these networks provide global connectivity and sustain the broad spectrum of the functions of the brain, the ... More

Clustering in complex networks. II. Percolation propertiesAug 15 2006Aug 17 2006The percolation properties of clustered networks are analyzed in detail. In the case of weak clustering, we present an analytical approach that allows to find the critical threshold and the size of the giant component. Numerical simulations confirm the ... More

Topology of the World Trade WebJan 02 2003Economy, and consequently trade, is a fundamental part of human social organization which, until now, has not been studied within the network modelling framework. Networks are mathematical tools used in the modelling of a wide variety of systems in social ... More

Spectral determination of semi-regular polygonsSep 18 2017Let us say that an $n$-sided polygon is semi-regular if it is circumscriptible and its angles are all equal but possibly one, which is then larger than the rest. Regular polygons, in particular, are semi-regular. We prove that semi-regular polygons are ... More

Zassenhaus Conjecture on torsion units holds for $\text{SL}(2,p)$ and $\text{SL}(2,p^2)$Mar 14 2018Apr 09 2018H.J. Zassenhaus conjectured that any unit of finite order and augmentation $1$ in the integral group ring $\mathbb{Z}G$ of a finite group $G$ is conjugate in the rational group algebra $\mathbb{Q}G$ to an element of $G$. We prove the Zassenhaus Conjecture ... More

Network-based confidence scoring system for genome-scale metabolic reconstructionsAug 18 2010Reliability on complex biological networks reconstructions remains a concern. Although observations are getting more and more precise, the data collection process is yet error prone and the proofs display uneven certitude. In the case of metabolic networks, ... More

Weighted Configuration ModelJan 31 2005The configuration model is one of the most successful models for generating uncorrelated random networks. We analyze its behavior when the expected degree sequence follows a power law with exponent smaller than two. In this situation, the resulting network ... More

Entropy/information flux in Hawking radiationDec 07 2015Nov 25 2017Blackbody radiation contains (on average) an entropy of 3.9\pm2.5 bits per photon. If the emission process is unitary, then this entropy is exactly compensated by "hidden information" in the correlations. We extend this argument to the Hawking radiation ... More

Staircase skew Schur functions are Schur P-positiveAug 10 2011We prove Stanley's conjecture that, if delta_n is the staircase shape, then the skew Schur functions s_{delta_n / mu} are non-negative sums of Schur P-functions. We prove that the coefficients in this sum count certain fillings of shifted shapes. In particular, ... More

Power Challenges of Large Scale Research Infrastructures: the Square Kilometer Array and Solar Energy Integration; Towards a zero-carbon footprint next generation telescopeOct 17 2012The Square Kilometer Array (SKA) will be the largest Global science project of the next two decades. It will encompass a sensor network dedicated to radioastronomy, covering two continents. It will be constructed in remote areas of South Africa and Australia, ... More

Subhaloes gone Notts: Subhaloes as tracers of the dark matter halo shapeJan 09 2014Sep 10 2014We study the shapes of subhalo distributions from four dark-matter-only simulations of Milky Way type haloes. Comparing the shapes derived from the subhalo distributions at high resolution to those of the underlying dark matter fields we find the former ... More

Profiling lung cancer patients using electronic health recordsSep 18 2018If Electronic Health Records contain a large amount of information about the patients condition and response to treatment, which can potentially revolutionize the clinical practice, such information is seldom considered due to the complexity of its extraction ... More

Towards an Abstract Domain for Resource Analysis of Logic Programs Using Sized TypesAug 19 2013We present a novel general resource analysis for logic programs based on sized types.Sized types are representations that incorporate structural (shape) information and allow expressing both lower and upper bounds on the size of a set of terms and their ... More

Dynamical control of the constraints growth in free evolutions of Einstein's equationsApr 17 2003I present a new, simple method to dynamically control the growth of the discretized constraints during a free evolution of Einstein's equations. During an evolution, any given family of formulations is adjusted off the constraints surface in a way such ... More

Digital interferometric demodulation of Placido mires applied to corneal topographyApr 10 2012Apr 17 2012This paper presents a novel digital interferometric method to demodulate Placido fringe patterns. This is a synchronous method which uses a computer-stored conic-wavefront as demodulating reference. Here we focus on the experimental aspects to phase-demodulate ... More

Synchronous phase-demodulation of high spatial frequency, concentric-rings, Placido fringe patternsMar 08 2012Apr 17 2012Here a synchronous phase-demodulation method for high spatial frequency (HSF), concentric-rings Placido fringe pattern is proposed. The earliest use of this concentric-rings pattern was to gauge non-spherical irregularities of the human cornea by Portuguese ... More

On Methods for the Formal Specification of Fault Tolerant SystemsJul 08 2012This paper introduces different views for understanding problems and faults with the goal of defining a method for the formal specification of systems. The idea of Layered Fault Tolerant Specification (LFTS) is proposed to make the method extensible to ... More

A Supersymmetric Explanation of the Excess of Higgs--Like Events at the LHC and at LEPOct 24 2012Nov 29 2012The LHC collaborations have recently announced evidence for the production of a "Higgs--like" boson with mass near 125 GeV. The properties of the new particle are consistent (within still quite large uncertainties) with those of the Higgs boson predicted ... More

Supersymmetric Dark Matter 2004Oct 07 2004Recent cosmological data allow to determine the universal Dark Matter (DM) density to a precision of about 10%, if a simple, well-motivated ansatz for the spectrum of primordial density perturbations is correct. Not surprisingly, a thermal neutralino ... More

Recent Developments in Dark Matter PhysicsMar 07 1997After a short review of the arguments for the existence of Particle Dark Matter in the Universe, I list the most plausible candidates provided by particle physics, i.e. neutrinos, axions, and WIMPs. In each case I briefly describe how to estimate the ... More

An Introduction to SupersymmetryNov 25 1996A fairly elementary introduction to supersymmetric field theories in general and the minimal supersymmetric Standard Model (MSSM) in particular is given. Topics covered include the cancellation of quadratic divergencies, the construction of the supersymmetric ... More

Multiple Interactions in gamma gamma CollisionsJun 29 1995The cross--section for two--photon events with (at least) two independent partonic scatters is estimated, for LEP energies as well as a 500 GeV ``photon collider". This results in events with (at least) four central (mini--)jets. Such events might be ... More

Complexity Classification in Infinite-Domain Constraint SatisfactionJan 04 2012Sep 14 2016A constraint satisfaction problem (CSP) is a computational problem where the input consists of a finite set of variables and a finite set of constraints, and where the task is to decide whether there exists a satisfying assignment of values to the variables. ... More

An Application of Rational Trees in a Logic Programming Interpreter for a Procedural LanguageMar 16 2004We describe here a simple application of rational trees to the implementation of an interpreter for a procedural language written in a logic programming language. This is possible in languages designed to support rational trees (such as Prolog II and ... More

Formality of Positive Quaternion Kaehler ManifoldsNov 17 2009Dec 17 2011Positive Quaternion Kaehler Manifolds are Riemannian manifolds with holonomy contained in Sp(n)Sp(1) and with positive scalar curvature. Conjecturally, they are symmetric spaces. We offer a new approach to this field of study via Rational Homotopy Theory, ... More

Computational complexity of topological invariantsDec 05 2011We answer the following question posed by Lechuga: Given a simply-connected space $X$ with both $H_*(X,\qq)$ and $\pi_*(X)\otimes \qq$ being finite-dimensional, what is the computational complexity of an algorithm computing the cup-length and the rational ... More

Partial Classification Results for Positive Quaternion Kaehler ManifoldsNov 24 2009Positive Quaternion Kaehler Manifolds are Riemannian manifolds with holonomy contained in Sp(n)Sp(1) and with positive scalar curvature. Conjecturally, they are symmetric spaces. We prove this conjecture in dimension 20 under additional assumptions and ... More

Cohomological consequences of (almost) free torus actionsApr 27 2012The long-standing Halperin--Carlsson conjecture (basically also known as the toral rank conjecture) states that the sum of all Betti numbers of a well-behaved space $X$ (with cohomology taken with coefficients in the cyclic group $\zz_p$ in characteristic ... More

A note on the Hilali conjectureJan 13 2015In this short note we observe that the Hilali conjecture holds for two-stage spaces, i.e. we argue that the dimension of the rational cohomology is at least as large as the dimension of the rational homotopy groups for these spaces. We also prove the ... More

Three-body repulsive forces among identical bosons in one dimensionFeb 05 2019I consider non-relativistic bosons interacting via pairwise potentials with infinite scattering length and supporting no two-body bound states. To lowest order in effective field theory, these conditions lead to non-interacting bosons, since the coupling ... More

Disformal Transformations in Scalar-Torsion GravityMay 01 2019We study disformal transformations in the context of scalar extensions to teleparallel gravity, in which the gravitational interaction is mediated by the torsion of a flat, metric compatible connection. We find a generic class of scalar-torsion actions ... More

Dg algebras with enough idempotents, their dg modules and their derived categoriesDec 14 2016May 02 2017We develop the theory dg algebras with enough idempotents and their dg modules and show their equivalence with that of small dg categories and their dg modules. We introduce the concept of dg adjunction and show that the classical covariant tensor-Hom ... More