Results for "Elisa Prandini"

total 937took 0.11s
A TeV source in the 3C 66A/B regionJul 06 2009The MAGIC telescope observed the region around the distant blazar 3C 66A for 54.2 hr in 2007 August-December. The observations resulted in the discovery of a gamma-ray source centered at celestial coordinates R.A. = 2h23m12s and decl.= 43deg 0.7arcmin ... More
Estimating the redshift of PKS 0447-439 through its GeV-TeV emissionOct 18 2011Jun 30 2012Context. Blazars are radio-loud active galactic nuclei (AGN) with a jet pointing at small angles towards the observer. The overall emitted spectrum is typically non-thermal, and in some cases the emission and/or absorption lines are so faint as to prevent ... More
TeV blazars and their distanceJan 26 2011Feb 01 2011Recently, a new method to constrain the distance of blazars with unknown redshift using combined observations in the GeV and TeV regimes has been developed, with the underlying assumption that the Very High Energy (VHE) spectrum corrected for the absorption ... More
Blazars distance indications from Fermi and TeV dataJan 21 2011A new method to constrain the distance of blazars with unknown redshift using combined observations in the GeV and TeV regimes will be presented. The underlying assumption is that the Very High Energy (VHE) spectrum corrected for the absorption of TeV ... More
Slope equalities for genus 5 surface fibrationsJun 15 2010K. Konno proved a slope equality for fibred surfaces with fibres of odd genus and general fibre of maximal gonality. More precisely he found a relation between the invariants of the fibration and certain weights of special fibres (called the Horikawa ... More
Exotics Searches at ATLASMay 03 2013May 08 2013An overview of recent searches for exotic signatures using the ATLAS detector at the LHC is given. The results presented use data collected at center-of-mass energies of $\sqrt{s}$ = 7 TeV and $\sqrt{s}$ = 8 TeV, for datasets corresponding to a variety ... More
The G-biliaison class of symmetric determinantal schemesMay 19 2005Dec 13 2006We consider a family of schemes, that are defined by minors of a homogeneous symmetric matrix with polynomial entries. We assume that they have maximal possible codimension, given the size of the matrix and of the minors that define them. We show that ... More
Simple Non-Rational Convex Polytopes via Symplectic GeometryApr 30 1999Feb 04 2000In this article we consider a generalization of manifolds and orbifolds which we call quasifolds; quasifolds of dimension k are locally isomorphic to the quotient of R^k by the action of a discrete group - tipically they are not Hausdorff topological ... More
Sur une généralisation de la notion de V-variétéApr 30 1999Nous consid\'erons un espace topologique qui est localement isomorphe au quotient de R^k par l'action d'un groupe discret et nous l'appelons quasi-vari\'et\'e de dimension k. Les quasi-vari\'et\'es g\'en\'eralisent les vari\'et\'es et les V-vari\'et\'es ... More
Commissioning of the ATLAS Muon Trigger SelectionSep 30 2010The performance of the three-level ATLAS muon trigger as evaluated by using LHC data is presented. Events have been selected by using only the hardware-based Level-1 trigger in order to commission and to subsequently enable the (software-based) selections ... More
Rank-metric codesFeb 07 2019This is a chapter of the upcoming "A Concise Encyclopedia of Coding Theory", W.C. Huffman, J.-L. Kim, and P. Sole' Eds., CRC Press. The chapter gives an introduction to the mathematical theory of rank-metric codes. Treated topics include: definition of ... More
QuasifoldsOct 19 2017Quasifolds are singular spaces that generalize manifolds and orbifolds. They are locally modeled by manifolds modulo the smooth action of countable groups and they are typically not Hausdorff. If the countable groups happen to be all finite, then quasifolds ... More
B Physics at CDFMay 31 2010We present the latest B physics results from the CDF experiment at the Fermilab Tevatron collider. We focus on a number of analyses, including a measurement of the forward-backward asymmetry of B -> K^(*) mu mu decays, determination of the CP violating ... More
On boundedly generated subgroups of profinite groupsDec 30 2013Mar 24 2014In this paper we investigate the following general problem. Let $G$ be a group and let $i(G)$ be a property of $G$. Is there an integer $d$ such that $G$ contains a $d$-generated subgroup $H$ with $i(H)=i(G)$? Here we consider the case where $G$ is a ... More
Thin-walled beams with a cross-section of arbitrary geometry: derivation of linear theories starting from 3D nonlinear elasticityJun 30 2011The subject of this paper is the rigorous derivation of lower dimensional models for a nonlinearly elastic thin-walled beam whose cross-section is given by a thin tubular neighbourhood of a smooth curve. Denoting by h and {\delta}_h, respectively, the ... More
CP (and CPT) violation studies at the Super Flavour FactoriesJan 13 2011In this talk we present the perspectives about measurements of CP and CPT violating quantities at future Super Flavour Factories. In particular we will focus on the expected sensitivities reachable after 5 years of data taking with the SuperB detector: ... More
Lifting the determinantal propertyNov 22 2006Aug 13 2007In this note we study standard and good determinantal schemes. We show that there exist arithmetically Cohen-Macaulay schemes that are not standard determinantal, and whose general hyperplane section is good determinantal. We prove that if a general hyperplane ... More
16th International Conference in Quantum ChromoDynamics: Charmonium-like states at BaBarSep 17 2013We present new results on charmonium-like states from the BaBar experiment located at the PEP-II asymmetric energy $e^+e^-$ collider at the SLAC National Accelerator Laboratory.
Symmetric ladders and G-biliaisonSep 25 2008Jan 25 2010We study the family of ideals generated by minors of mixed size contained in a ladder of a symmetric matrix from the point of view of liaison theory. We prove that they can be obtained from ideals of linear forms by ascending G-biliaison. In particular, ... More
A generalized Gaeta's TheoremJan 16 2007We generalize Gaeta's Theorem to the family of determinantal schemes. In other words, we show that the schemes defined by minors of a fixed size of a matrix with polynomial entries belong to the same G-biliaison class of a complete intersection whenever ... More
A new proof of the Alexander-Hirschowitz interpolation TheoremMar 01 2010The classical polynomial interpolation problem in several variables can be generalized to the case of points with greater multiplicities. What is known, as yet, is essentially concentrated in the Alexander-Hirschowitz Theorem which says that a general ... More
Infinite horizon Stochastic Optimal Control for Volterra equations with completely monotone kernelsJan 21 2014The aim of the paper is to study an optimal control problem on infinite horizon for an infinite dimensional integro-differential equation with completely monotone kernelskernels, where we assume that the noise enters the system when we introduce a control. ... More
A negative answer to a conjecture arising in the study of selection-migration models in population geneticsJan 26 2017We deal with the study of the evolution of the allelic frequencies, at a single locus, for a population distributed continuously over a bounded habitat. We consider evolution which occurs under the joint action of selection and arbitrary migration, that ... More
Small time asymptotic on the diagonal for Hörmander's type hypoelliptic operatorsFeb 23 2015Jun 27 2015We compute the small time asymptotic of the fundamental solution of H\"ormander's type hypoelliptic operators with drift, at a stationary point, $x_0$, of the drift field. We show that the order of the asymptotic depends on the controllability of an associated ... More
Light vector meson production at the LHC with the ALICE detectorSep 13 2012Sep 24 2012The measurement of light vector meson production (\rho, \omega, \phi) in pp collisions provides insight into soft Quantum Chromodynamics (QCD) processes in the LHC energy range. Calculations in this regime are based on QCD inspired phenomenological models ... More
The Ultraviolet-X-ray connection in AGN outflowsNov 10 2010In this paper I review the recent progress in understanding the physics of the gas outflowing from active galactic nuclei and its impact on the surrounding environment, using the combined information provided by multiwavelength Ultraviolet-X-ray campaigns. ... More
Linearized plastic plate models as Gamma-limits of 3D finite elastoplasticityMay 02 2013The subject of this paper is the rigorous derivation of reduced models for a thin plate by means of {\Gamma}-convergence, in the framework of finite plasticity. Denoting by {\epsilon} the thickness of the plate, we analyse the case where the scaling factor ... More
Charm baryon production in pp, p-Pb and Pb-Pb collisions with ALICE at the LHCFeb 28 2019In this contribution, the latest ALICE results on charmed baryon production are presented. In particular the measurements of $\Lambda_{\rm c}^{+}$-baryon production in pp collisions at ${\sqrt{\rm s}}$ = 5.02 TeV and in p-Pb collisions at $\sqrt{\rm s_{NN}}$ ... More
Mixed ladder determinantal varieties from two-sided laddersOct 25 2005Apr 21 2006We study the family of ideals defined by mixed size minors of two-sided ladders of indeterminates. We compute their Groebner bases with respect to a skew-diagonal monomial order, then we use them to compute the height of the ideals. We show that these ... More
Secant Degree of Toric Surfaces and Delightful Planar Toric DegenerationsDec 11 2010The $k$-secant degree is studied with a combinatorial approach. A planar toric degeneration of any projective toric surface $X$ corresponds to a regular unimodular triangulation $D$ of the polytope defining $X$. If the secant ideal of the initial ideal ... More
A new upper limit on the redshift of PG 1553+113 from observations with the MAGIC TelescopeJul 01 2009Very high energy gamma ray emission from the active galactic nucleus PG 1553+113 was observed during 2005 and 2006 by the MAGIC collaboration, for a total observation time of 18.8 hours. Here we present the results of follow up observations: more than ... More
Supermassive black holes at high redshiftsMar 14 2019MeV blazars are the most luminous persistent sources in the Universe and emit most of their energy in the MeV band. These objects display very large jet powers and accretion luminosities and are known to host black holes with a mass often exceeding $10^9 ... More
Homogenization for A-quasiconvexity with variable coefficientsMay 26 2016A homogenization result for a family of oscillating integral energies is presented, where the fields under consideration are subjected to first order linear differential constraints depending on the space variable x. The work is based on the theory of ... More
Interactions of cosmological gravitational waves and magnetic fieldsSep 08 2008Jan 05 2009The energy momentum tensor of a magnetic field always contains a spin-2 component in its anisotropic stress and therefore generates gravitational waves. It has been argued in the literature (Caprini & Durrer \cite{CD}) that this gravitational wave production ... More
On Hyperfocused Arcs in PG(2,q)Jan 20 2006A k-arc in a Dearguesian projective plane whose secants meet some external line in k-1 points is said to be hyperfocused. Hyperfocused arcs are investigated in connection with a secret sharing scheme based on geometry due to Simmons. In this paper it ... More
Generalized toric varieties for simple non-rational convex polytopesApr 11 2000Jun 01 2001We call complex quasifold of dimension k a space that is locally isomorphic to the quotient of an open subset of the space C^k by the holomorphic action of a discrete group; the analogue of a complex torus in this setting is called a complex quasitorus. ... More
Compression for trace zero points on twisted Edwards curvesJul 27 2015We propose two optimal representations for the elements of trace zero subgroups of twisted Edwards curves. For both representations, we provide efficient compression and decompression algorithms. The efficiency of the algorithm is compared with the efficiency ... More
Patterns of variability in Be/X-ray pulsars during giant outburstsDec 24 2012Feb 12 2013The discovery of source states in the X-ray emission of black-hole binaries and neutron-star low-mass X-ray binaries constituted a major step forward in the understanding of the physics of accretion onto compact objects. While there are numerous studies ... More
Can supernova kicks trigger EMRIs in the Galactic Centre?Feb 12 2019One of the most promising gravitational wave (GW) sources detectable by the forthcoming LISA observatory are the so-called extreme-mass ratio inspirals (EMRIs), i.e. GW-driven inspirals of stellar-mass compact objects onto supermassive black holes (SMBHs). ... More
An indefinite nonlinear problem in population dynamics: high multiplicity of positive solutionsDec 09 2017Reaction-diffusion equations have several applications in the field of population dynamics and some of them are characterized by the presence of a factor which describes different types of food sources in a heterogeneous habitat. In this context, to study ... More
Construction of Brauer-Severi VarietiesJun 30 2017Dec 12 2018In this paper we give an algorithm for computing equations of Brauer-Severi varieties over perfect fields of characteristic 0. As an example we show the equations of all Brauer-Severi surfaces defined over $\mathbb{Q}$.
The Cauchy-Crofton formula and the Whitney arc property for definable setsDec 15 2008Nov 07 2010We use the Cauchy-Crofton formula to show that every definable cell (bounded by a ball with rational radius) in an O-minimal expansion of a field extension of the real numbers satisfies the Whitney arc property.
Ammann Tilings in Symplectic GeometryApr 14 2010Mar 06 2013In this article we study Ammann tilings from the perspective of symplectic geometry. Ammann tilings are nonperiodic tilings that are related to quasicrystals with icosahedral symmetry. We associate to each Ammann tiling two explicitly constructed highly ... More
On the global generalized solvability of a chemotaxis model with signal absorption and logistic growth termsMay 23 2018Introducing a suitable solution concept, we show that in bounded smooth domains $\Omega\subset \mathbb{R}^n$, $n\ge 1$, the initial boundary value problem for the chemotaxis system \begin{align*} u_t&=\Delta u -\chi\nabla\cdot\left(\frac{u}{v}\nabla v\right)+\kappa ... More
Carleman estimates for the parabolic transmission problem and Hölder propagation of smallness across an interfaceJun 11 2017In this paper we prove a H\"older propagation of smallness for solutions to second order parabolic equations whose general anisotropic leading coefficient has a jump at an interface. We assume that the leading coefficient is Lipschitz continuous with ... More
Bare Action and Regularized Functional Integral of Asymptotically Safe Quantum GravityNov 24 2008Dec 12 2008Investigations of Quantum Einstein Gravity (QEG) based upon the effective average action employ a flow equation which does not contain any ultraviolet (UV) regulator. Its renormalization group trajectories emanating from a non-Gaussian fixed point define ... More
Curvature terms in small time heat kernel expansion for a model class of hypoelliptic Hörmander operatorsOct 16 2015We consider the heat equation associated with a class of second order hypoelliptic H\"{o}rmander operators with constant second order term and linear drift. We describe the possible small time heat kernel expansion on the diagonal giving a geometric characterization ... More
Untangling the role of diverse social dimensions in the diffusion of microfinanceSep 06 2016Ties between individuals on a social networks can represent different dimensions of interactions, and the spreading of information and innovations on these networks could potentially be driven by some dimensions more than by others. In this paper we investigate ... More
An algebraic framework for end-to-end physical-layer network codingNov 14 2016We propose an algebraic setup for end-to-end physical-layer network coding based on submodule transmission. We introduce a distance function between modules, describe how it relates to information loss and errors, and show how to compute it. Then we propose ... More
Three positive solutions to an indefinite Neumann problem: a shooting methodJun 09 2017We deal with the Neumann boundary value problem \begin{equation*} \begin{cases} \, u" + \bigl{(} \lambda a^{+}(t)-\mu a^{-}(t) \bigr{)}g(u) = 0, \\ \, 0 < u(t) < 1, \quad \forall\, t\in\mathopen{[}0,T\mathclose{]},\\ \, u'(0) = u'(T) = 0, \end{cases} ... More
Two-well rigidity and multidimensional sharp-interface limits for solid-solid phase transitionsOct 15 2018Oct 30 2018We establish a quantitative rigidity estimate for two-well frame-indifferent nonlinear energies, in the case in which the two wells have exactly one rank-one connection. Building upon this novel rigidity result, we then analyze solid-solid phase transitions ... More
La réduction de termes complexes dans les langues de spécialitéNov 23 2010Aug 19 2011Our study applies statistical methods to French and Italian corpora to examine the phenomenon of multi-word term reduction in specialty languages. There are two kinds of reduction: anaphoric and lexical. We show that anaphoric reduction depends on the ... More
Equidistant subspace codesJul 07 2015In this paper we study equidistant subspace codes, i.e. subspace codes with the property that each two distinct codewords have the same distance. We provide an almost complete classification of such codes under the assumption that the cardinality of the ... More
Analytical validation of the Yound-Dupré law for epitaxially-strained thin filmsSep 26 2018We present here an analysis of the regularity of minimizers of a variational model for epitaxially strained thin-films identified by the authors in the companion paper [Davoli E., Piovano P., Derivation of a heteroepitaxial thin-film model. Submitted ... More
Index Calculus in the Trace Zero VarietyMay 05 2014Feb 23 2015We discuss how to apply Gaudry's index calculus algorithm for abelian varieties to solve the discrete logarithm problem in the trace zero variety of an elliptic curve. We treat in particular the practically relevant cases of field extensions of degree ... More
The asymptotic expansion of the regular discretization error of Itô integralsFeb 21 2018We study a Edgeworth-type refinement of the central limit theorem for the discretizacion error of It\^o integrals. Towards this end, we introduce a new approach, based on the anticipating It\^o formula. This alternative technique allows us to compute ... More
Feedback Optimal Control for Stochastic Volterra Equations with Completely Monotone KernelsDec 16 2011In this paper we are concerned with a class of stochastic Volterra integro-differential problems with completely monotone kernels, where we assume that the noise enters the system when we introduce a control. We start by reformulating the state equation ... More
On the connection between compression learning and scenario based optimizationMar 04 2014Mar 06 2014We investigate the connections between compression learning and scenario based optimization. We first show how to strengthen, or relax the consistency assumption at the basis of compression learning and study the learning and generalization properties ... More
Performance assessment and design of abstracted models for stochastic hybrid systems through a randomized approachMay 28 2014In this paper, a simulation-based method for the analysis and design of abstracted models for a stochastic hybrid system is proposed. The accuracy of a model is evaluated in terms of its capability to reproduce the system output for all the realizations ... More
Neural RelaxJul 27 2011Jun 18 2012We present an algorithm for data preprocessing of an associative memory inspired to an electrostatic problem that turns out to have intimate relations with information maximization.
Higher spin interactions with scalar matter on constant curvature spacetimes: conserved current and cubic coupling generating functionsJul 26 2010Nov 12 2010Cubic couplings between a complex scalar field and a tower of symmetric tensor gauge fields of all ranks are investigated on any constant curvature spacetime of dimension d>2. Following Noether's method, the gauge fields interact with the scalar field ... More
Role of van der Waals bonding in layered oxide: Bulk vanadium pentoxideJun 12 2010Sparse matter is characterized by regions with low electron density and its understanding calls for methods to accurately calculate both the van der Waals (vdW) interactions and other bonding. Here we present a first-principles density functional theory ... More
The open story of the magnetic fluxesFeb 16 2005Feb 24 2005We discuss the effects of oblique internal magnetic fields on the spectrum of type I superstrings compactified on tori. In particular we derive general formulae for the magnetic shifts and multiplicities of open strings connecting D9-branes with arbitrary ... More
Duistermaat-Heckman measures in a non-compact settingJul 21 1993We prove a \dh type formula in a suitable non-compact setting. We use this formula to evaluate explicitly the pushforward of the Liouville measure via the moment map of both an abelian and a non-abelian group action. As an application we obtain the classical ... More
Vanadium pentoxide (V2O5): a van der Waals density functional studyJul 18 2010The past few years has brought renewed focus on the physics behind the class of materials characterized by long-range interactions and wide regions of low electron density, sparse matter. There is now much work on developing the appropriate algorithms ... More
Pole Placement with Fields of Positive CharacteristicDec 15 2009The pole placement problem belongs to the classical problems of linear systems theory. It is often assumed that the ground field is the real numbers R or the complex numbers C. The major result over the complex numbers derived in 1981 by Brockett and ... More
Partial Spreads in Random Network CodingJun 24 2013Following the approach by R. K\"otter and F. R. Kschischang, we study network codes as families of k-dimensional linear subspaces of a vector space F_q^n, q being a prime power and F_q the finite field with q elements. In particular, following an idea ... More
The canonical ring of a 3-connected curveJul 27 2011Apr 23 2013Let C be a projective curve either reduced with planar singularities or contained in a smooth algebraic surface. We show that the canonical ring R(C, \omega_C)= \oplus_{k \geq 0} H^0(C, \omega_C^k is generated in degree 1 if C is 3-connected and not (honestly) ... More
One dimensional fractional order $TGV$: Gamma-convergence and bilevel training schemeDec 15 2016Oct 09 2017New fractional $r$-order seminorms, $TGV^r$, $r\in \mathbb R$, $r\geq 1$, are proposed in the one-dimensional (1D) setting, as a generalization of the integer order $TGV^k$-seminorms, $k\in\mathbb{N}$. The fractional $r$-order $TGV^r$-seminorms are shown ... More
Analysis of the stochastic FitzHugh-Nagumo systemJan 15 2008In this paper we study a system of stochastic differential equations with dissipative nonlinearity which arise in certain neurobiology models. Besides proving existence, uniqueness and continuous dependence on the initial datum, we shall be mainly concerned ... More
Beyond the mesh handling Maxwell's curl equations with an unconditionally leapfrog stable schemeApr 26 2013Numerical solution of equations governing time domain simulations in computational electromagnetics, is usually based on grid methods in space and on explicit schemes for the time evolution. A predefined grid in the problem domain and a stability step ... More
Homogenization of Integral Energies Under Periodically Oscillating Differential ConstraintsAug 20 2015A homogenization result for a family of integral energies is presented, where the fields are subjected to periodic first order oscillating differential constraints in divergence form. The work is based on the theory of A -quasiconvexity with variable ... More
Computing the dimension of ideals in group algebras, with an application to coding theoryMar 31 2014We study the problem of computing the dimension of a left/right ideal in a group algebra F[G] of a finite group G over a field F, by relating the dimension to the rank of an appropriate matrix, originating from a regular right/left representation of G. ... More
Multiangle static and dynamic light scattering in the intermediate scattering angle rangeAug 31 2012We describe a light scattering apparatus based on a novel optical scheme covering the scattering angle range $0.5\dg \le \theta \le 25\dg$, an intermediate regime at the frontier between wide angle and small angle setups that is difficult to access by ... More
Restoring of optical resonances in subwavelength hyperbolic etalonsSep 23 2011We give a solution to the fundamental problem of restoring optical resonances in deep subwavelength structures by resorting to indefinite metamaterials. We prove that a nanometric thick hyperbolic slab with very small permittivities exhibits etalon resonances ... More
Gauge thresholds in the presence of oblique magnetic fluxesJun 11 2005Mar 13 2006We compute the one-loop partition function and analyze the conditions for tadpole cancellation in type I theories compactified on tori in the presence of internal oblique magnetic fields. We check open - closed string channel duality and discuss the effect ... More
Twists of non-hyperelliptic curvesMar 11 2015In this paper we show a method for computing the set of twists of a non-singular projective curve defined over an arbitrary (perfect) field $k$. The method is based on a correspondence between twists and solutions to a Galois embedding problem. When in ... More
Pairing and condensation in a resonant Bose-Fermi mixtureJan 12 2010We study by diagrammatic methods a mixture of single-component bosons and fermions, with boson-fermion coupling tuned by a Fano-Feshbach resonance. For increasing coupling, the growing boson-fermion pairing correlations progressively reduce the boson ... More
Untangling the role of diverse social dimensions in the diffusion of microfinanceSep 06 2016Nov 24 2016Ties between individuals on a social network can represent different dimensions of interactions, and the spreading of information and innovations on these networks could potentially be driven by some dimensions more than by others. In this paper we investigate ... More
Correlation Effects in Quantum Dot Wave Function ImagingJul 28 2005Jul 29 2005We demonstrate that in semiconductor quantum dots wave functions probed by imaging techniques based on local tunneling spectroscopies like STM show characteristic signatures of electron-electron Coulomb correlation. We predict that such images correspond ... More
A Petri Theorem for Rank 2 Bundles with Canonical DeterminantMar 26 2001Jul 05 2002This paper establishes the correctness of a conjecture of Bertram-Feinberg and Mukai for a special class of globally generated rank-two bundles with canonical determinant over a generic Riemann surface of genus at least four.
Scale factor duality in quintessence models ?May 16 2001We consider several kinds of quintessence models in the framework of scale factor duality. We show that this symmetry exists only for a very small number of quintessence potentials. We then apply the duality transformations found to several analytical ... More
Nonrational Symplectic Toric CutsJun 02 2016In this article we extend cutting and blowing up to the nonrational symplectic toric setting. This entails the possibility of cutting and blowing up for symplectic toric manifolds and orbifolds in nonrational directions.
Positivity of divisors on blown-up projective spacesJun 15 2015Feb 22 2016We study $l$-very ample, ample and semi-ample divisors on the blown-up projective space $\mathbb{P}^n$ in a collection of points in general position. We establish Fujita's conjectures for all ample divisors with the number of points bounded above by $2n$ ... More
The possible degrees of the group of a toroidal map of type {4, 4}Aug 29 2018In this paper we list all possible degrees of a faithful transitive permutation representation of the group of symmetries of a regular map of type {4,4}. For the map {4,4}_(s,0) the possible degrees are n = 2ab, 4ab and 8ab with s = lcm(a; b); and for ... More
Enumerating permutations avoiding more than three Babson - Steingr\'ı msson patternsApr 26 2007Not long ago, Claesson and Mansour proposed some conjectures about the enumeration of the permutations avoiding more than three Babson - Steingr\'\i msson patterns (generalized patterns of type $(1,2)$ or $(2,1)$). The avoidance of one, two or three patterns ... More
Secant varieties of Segre-Veronese embeddings of (P^1)^rMay 11 2011We use a double degeneration technique to calculate the dimension of the secant variety of any Segre-Veronese embedding of (P^1)^r
Corporate payments networks and credit risk ratingNov 21 2017Sep 22 2018Aggregate and systemic risk in complex systems are emergent phenomena depending on two properties: the idiosyncratic risks of the elements and the topology of the network of interactions among them. While a significant attention has been given to aggregate ... More
The Symplectic Geometry of Penrose Rhombus TilingsNov 11 2007Apr 24 2008The purpose of this article is to view Penrose rhombus tilings from the perspective of symplectic geometry. We show that each thick rhombus in such a tiling can be naturally associated to a highly singular 4-dimensional compact symplectic space, while ... More
Vanishing theorems for linearly obstructed divisorsMar 26 2014Jan 21 2017We study divisors in the blow-up of $\mathbb{P}^n$ at points in general position that are non-special with respect to the notion of linear speciality introduced in [5]. We describe the cohomology groups of their strict transforms via the blow-up of the ... More
An interface-free multi-scale multi-order model for traffic flowMay 22 2018Feb 22 2019In this paper we present a new kind of model for traffic flow which couples a first-order macroscopic approach with a second-order microscopic approach, avoiding any interface or boundary conditions between them. The Euler-Godunov scheme associated to ... More
Toric Geometry of the Regular Convex PolyhedraNov 30 2016In this article, we describe symplectic and complex toric spaces associated to the five regular convex polyhedra. The regular tetrahedron and the cube are rational and simple, the regular octahedron is not simple, the regular dodecahedron is not rational ... More
Posets and Permutations in the Duplication-Loss Model: Minimal Permutations with d DescentsJun 09 2008In this paper, we are interested in the combinatorial analysis of the whole genome duplication - random loss model of genome rearrangement initiated in a paper of Chaudhuri, Chen, Mihaescu, and Rao in SODA 2006 and continued by Bouvel and Rossin in 2007. ... More
Anderson localization in optical lattices with correlated disorderOct 17 2015We study the Anderson localization of atomic gases exposed to simple-cubic optical lattices with a superimposed disordered speckle pattern. The two mobility edges in the first band and the corresponding critical filling factors are determined as a function ... More
Anderson localization of matter waves in quantum-chaos theoryMar 14 2015Jun 16 2015We study the Anderson localization of atomic gases exposed to three-dimensional optical speckles by analyzing the statistics of the energy-level spacings. This method allows us to consider realistic models of the speckle patterns, taking into account ... More
Zero-Temperature Equation of State and Phase Diagram of Repulsive Fermionic MixturesApr 15 2014Apr 17 2014We compute the zero-temperature equation of state of a mixture of two fermionic atomic species with repulsive interspecies interactions using second-order perturbation theory. We vary the interaction strength, the population and the mass imbalance, and ... More
Single-particle spectral functions in the normal phase of a strongly-attractive Bose-Fermi mixtureMay 28 2013We calculate the single-particle spectral functions and quasi-particle dispersions for a Bose-Fermi mixture when the boson-fermion attraction is sufficiently strong to suppress completely the condensation of bosons at zero temperature. Within a T-matrix ... More
Lipschitz stability for the electrical impedance tomography problem: the complex caseAug 24 2010In this paper we investigate the boundary value problem ${div(\gamma\nabla u)=0 in \Omega, u=f on \partial\Omega$ where $\gamma$ is a complex valued $L^\infty$ coefficient, satisfying a strong ellipticity condition. In Electrical Impedance Tomography, ... More
Imaging quasi-particle wavefunctions in quantum dots via tunneling spectroscopyAug 20 2004Oct 11 2004We show that in quantum dots the physical quantities probed by local tunneling spectroscopies, namely the quasi-particle wavefunctions of interacting electrons, can considerably deviate from their single-particle counterparts as an effect of Coulomb correlation. ... More
Discovery of a QPO in the X-ray pulsar 1A 1118-615: correlated spectral and aperiodic variabilityNov 02 2010Nov 03 2010Our goal is to investigate the X-ray timing and spectral variability of the high-mass X-ray binary 1A 1118-615 during a type-II outburst. We performed a detailed color, spectral and timing analysis of a giant outburst from 1A 1118-615, using RXTE data. ... More