Results for "Federico Faedo"

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Hairy black holes in N=2 gauged supergravityMay 12 2015May 22 2015We construct black holes with scalar hair in a wide class of four-dimensional N=2 Fayet-Iliopoulos gauged supergravity theories that are characterized by a prepotential containing one free parameter. Considering the truncated model in which only a single ... More
Quantum corrections to Higher-Dimensional TheoriesOct 31 2006This is a non-technical summary of the subtleties of quantum corrections on extra-dimensional theories: should one first renormalize and then mode expand, or first expand in four-dimensional modes and then renormalize?
Renormalized Kaluza-Klein theories II. $QED_4$ on a two-torusFeb 24 2006May 03 2006The contents of this paper have been incorporated in the new version of hep-th/0602150.
Rotating black holes in the FI-gauged $N=2$, $D=4$ $\overline{\mathbb{C}\text{P}}^n$ modelFeb 08 2019Mar 25 2019We construct supersymmetric black holes with rotation or NUT charge for the $\overline{\mathbb{C}\text{P}}^n$- and the $\text{t}^3$ model of $N=2$, $D=4$ $\text{U}(1)$ FI-gauged supergravity. The solutions preserve 2 real supercharges, which are doubled ... More
Renormalized Kaluza-Klein theoriesFeb 15 2006May 10 2006Using six-dimensional quantum electrodynamics ($QED_6$) as an example we study the one-loop renormalization of the theory both from the six and four-dimensional points of view. Our main conclusion is that the properly renormalized four dimensional theory ... More
A supersymmetric consistent truncation for conifold solutionsAug 04 2010Dec 15 2010We establish a supersymmetric consistent truncation of type IIB supergravity on the T^{1,1} coset space, based on extending the Papadopoulos-Tseytlin ansatz to the full set of SU(2)xSU(2) invariant Kaluza-Klein modes. The five-dimensional model is a gauged ... More
Constructing Lifshitz solutions from AdSFeb 25 2011Mar 08 2011Under general assumptions, we show that a gravitational theory in d+1 dimensions admitting an AdS solution can be reduced to a d-dimensional theory containing a Lifshitz solution with dynamical exponent z=2. Working in a d=4, N=2 supergravity setup, we ... More
Rotating black holes in the FI-gauged $N=2$, $D=4$ $\overline{\mathbb{C}\text{P}}^n$ modelFeb 08 2019We construct supersymmetric black holes with rotation or NUT charge for the $\overline{\mathbb{C}\text{P}}^n$- and the $\text{t}^3$ model of $N=2$, $D=4$ $\text{U}(1)$ FI-gauged supergravity. The solutions preserve 2 real supercharges, which are doubled ... More
One-loop effective potential in M4 x T2 with and without 't Hooft fluxNov 05 2009We review the basic notions of compactification in the presence of a background flux. In extra-dimentional models with more than five dimensions, Scherk and Schwarz boundary conditions have to satisfy 't Hooft consistency conditions. Different vacuum ... More
BPS domain walls in N=4 supergravity and dual flowsOct 30 2012Mar 21 2013We establish the conditions for supersymmetric domain wall solutions to N=4 gauged supergravity in five dimensions. These read as BPS first-order equations for the warp factor and the scalar fields, driven by a superpotential and supplemented by a set ... More
Rare Kaon Decays K->pi n n and KL->pi l+l-Dec 12 2005Over the next years, the Flavour Physics community will be looking for inconsistencies of the Standard Model (SM) by exploiting new and precise measurements. In these ``indirect new physics'' searches, the key strategy is to concentrate on observables, ... More
The IR-Completion of Gravity: What happens at Hubble Scales?Jul 06 2009Nov 30 2009We have recently proposed an "Ultra-Strong" version of the Equivalence Principle (EP) that is not satisfied by standard semiclassical gravity. In the theory that we are conjecturing, the vacuum expectation value of the (bare) energy momentum tensor is ... More
Backlund transformations for the elliptic Gaudin model and a Clebsch systemJan 25 2011A two-parameters family of Backlund transformations for the classical elliptic Gaudin model is constructed. The maps are explicit, symplectic, preserve the same integrals as for the continuous flows and are a time discretization of each of these flows. ... More
High availability using virtualizationOct 09 2009High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered ... More
A Note on Edwards' Hypothesis for Zero-Temperature Ising DynamicsOct 21 2004We give a simple criterion for checking the so called Edwards' hypothesis in certain zero-temperature, ferromagnetic spin-flip dynamics and use it to invalidate the hypothesis in various examples in dimension one and higher.
A population-based approach to background discrimination in particle physicsOct 28 2010Mar 15 2013Background properties in experimental particle physics are typically estimated using control samples corresponding to large numbers of events. This can provide precise knowledge of average background distributions, but typically does not consider the ... More
Closed graph theorems for bornological spacesAug 06 2015The aim of this paper is that of discussing Closed Graph Theorems for bornological vector spaces in a way which is accessible to non-experts. We will see how to easily adapt classical arguments of functional analysis over $\mathbb{R}$ and $\mathbb{C}$ ... More
Turbulent amplification of magnetic field driven by dynamo effect at rippled shocksApr 17 2013We derive analytically the vorticity generated downstream of a two-dimensional rippled hydromagnetic shock neglecting fluid viscosity and resistivity. The growth of the turbulent component of the downstream magnetic field is driven by the vortical eddies ... More
Optimal Polynomial Admissible Meshes on Some Classes of Compact Subsets of $\R^d$Feb 19 2013Dec 10 2015We show that any compact subset of $\R^d$ which is the closure of a bounded star-shaped Lipschitz domain $\Omega$, such that $\complement \Omega$ has positive reach in the sense of Federer, admits an \emph{optimal AM} (admissible mesh), that is a sequence ... More
Coarsening in inhomogeneous systemsApr 01 2015This Article is a brief review of coarsening phenomena occurring in systems where quenched features - such as random field, varying coupling constants or lattice vacancies - spoil homogeneity. We discuss the current understanding of the problem in ferromagnetic ... More
Brownian Loops and Conformal FieldsJan 20 2015Feb 11 2016The main topic of these lecture notes is the continuum scaling limit of planar lattice models. One reason why this topic occupies an important place in the theory of probability and mathematical statistical physics is that scaling limits provide the link ... More
Proportionality Principle for the Lipschitz simplicial volumeNov 01 2014We prove the Proportionality Principle for the Lipschitz simplicial volume without any restriction on curvature. Our argument is based on the construction of a suitable \emph{pseudostraightening} for simplices.
On a generalization of affinoid varietiesJan 22 2014Jun 20 2016In this thesis we develop the foundations for a theory of analytic geometry over a valued field, uniformly encompassing the case when the base field is equipped with a non-archimedean valuation and the case when it has an archimedean one. Our building ... More
Testing for separability is hardJan 18 2014This paper shows that it is computationally hard to decide (or test) if a consumption data set is consistent with separable preferences.
Reconstructing a website's lost past: Methodological issues concerning the history of www.unibo.itApr 20 2016This paper describes how born digital primary sources could be used to reconstruct the recent history of scientific institutions. The case study is an analysis of the first 25 years online of the University of Bologna. The focus of this work is primarily ... More
CLT for the zeros of Kostlan Shub Smale random polynomialsApr 21 2015Apr 23 2015In this paper we find the asymptotic main term of the variance of the number of roots of Kostlan-Shub-Smale random polynomials and prove a central limit theorem for the number of roots as the degree goes to infinity.
A sum-shuffle formula for zeta values in Tate algebrasSep 28 2016Oct 13 2016We prove a sum-shuffle formula for double zeta values in Tate algebras. This follows from an analog result for double twisted power sums, implying that an F\_p-vector space generated by multiple zeta values in Tate algebras is an F\_p-algebra.
On Natural Deduction for Herbrand Constructive Logics I: Curry-Howard Correspondence for Dummett's Logic LCSep 11 2016Sep 27 2016Dummett's logic LC is intuitionistic logic extended with Dummett's axiom: for every two statements the first implies the second or the second implies the first. We present a natural deduction and a Curry-Howard correspondence for first-order and second-order ... More
Infrared-modified UniverseApr 18 2012We consider a Hubble expansion law modified in the infra-red by distance-dependent terms, and attempt to enforce homogeneity upon it. As a warm-up, we re-derive the basic kinematics of a Friedman Robertson Walker universe without using standard general ... More
Neither Name, Nor NumberDec 20 2011Since its origins, Quantum mechanics has presented problems with the concept of individuality. It is argued that quantum particles do not have individuality, and so, one can speak about "entities without identity". On the contrary, we claim that the problem ... More
Towards Conformal Invariance and a Geometric Representation of the 2D Ising Magnetization FieldMay 14 2012We study the continuum scaling limit of the critical Ising magnetization in two dimensions. We prove the existence of subsequential limits, discuss connections with the scaling limit of critical FK clusters, and describe work in progress of the author ... More
Quadratic Vector EquationsApr 09 2010Jun 07 2011We study in an unified fashion several quadratic vector and matrix equations with nonnegativity hypotheses. Specific cases of such problems (QBD equations, nonsymmetric algebraic Riccati equations, Lu's simple equation, Markovian binary trees equations) ... More
Sufficient conditions for local solvability of some degenerate PDO with complex subprincipal symbolJun 29 2018Oct 02 2018We will show a local solvability result for a class of degenerate second order linear partial differential operators with a complex subprincipal symbol. Due to the form of the operators in the class the subprincipal symbol is invariantly defined and we ... More
The number of halving circlesAug 25 2004A set S of 2n+1 points in the plane is said to be in general position if no three points of S are collinear and no four are concyclic. A circle is called halving with respect to S if it has three points of S on its circumference, n-1 points in its interior, ... More
A nonlocal stochastic Cahn-Hilliard equationOct 27 2015Mar 07 2016We consider a stochastic extension of the nonlocal convective Cahn-Hilliard equation containing an additive Wiener process noise. We first introduce a suitable analytical setting and make some mathematical and physical assumptions. We then establish, ... More
Tutte polynomials of hyperplane arrangements and the finite field methodOct 04 2017The Tutte polynomial is a fundamental invariant associated to a graph, matroid, vector arrangement, or hyperplane arrangement. This short survey focuses on some of the most important results on Tutte polynomials of hyperplane arrangements. We show that ... More
Modifying Gravity in the Infra-Red by imposing an "Ultra-Strong" Equivalence PrincipleApr 28 2009Jul 04 2009The equivalence principle suggests to consider gravity as an infra-red phenomenon, whose effects are visible only outside Einstein's free-falling elevator. By curving spacetime, General Relativity leaves the smallest systems free of classical gravitational ... More
Glimmers of a pre-geometric perspectiveJun 15 2005Nov 20 2007Space-time measurements and gravitational experiments are made by using objects, matter fields or particles and their mutual relationships. As a consequence, any operationally meaningful assertion about space-time is in fact an assertion about the degrees ... More
The EPR Argument in a Relational Interpretation of Quantum MechanicsNov 03 2000It is shown that in the Rovelli relational interpretation of quantum mechanics, in which the notion of absolute or observer independent state is rejected, the conclusion of the ordinary EPR argument turns out to be frame-dependent, provided the conditions ... More
A survey on independence-based Markov networks learningAug 10 2011Nov 20 2013This work reports the most relevant technical aspects in the problem of learning the \emph{Markov network structure} from data. Such problem has become increasingly important in machine learning, and many other application fields of machine learning. ... More
The high energy frontier of ultrarelativistic nucleus-nucleus collisionsJul 20 2011An outlook on physics at the high energy frontier of nucleus-nucleus collisions is presented, on the basis of the new results presented at Quark Matter 2011 by the LHC and RHIC experiments.
A q-difference Baxter's operator for the Ablowitz-Ladik chainAug 07 2015We construct the Baxter's operator and the corresponding Baxter's equation for a quantum version of the Ablowitz Ladik model. The result is achieved by looking at the quantum analogue of the classical Backlund transformations. For comparison we find the ... More
Values of certain L-series in positive characteristicJul 22 2011Oct 03 2011We introduce a family of L-series specialising to both L-series associated to certain Dirichlet characters over F_q[T] and to integral values of Carlitz-Goss zeta function associated to F_q[T]. We prove, with the use of the theory of deformations of vectorial ... More
Evidence for Diboson Production in the Lepton plus Heavy Flavor Jets Final State at CDFFeb 02 2013This thesis presents the evidence, at 3.08 sigma, for the associate production of massive vector bosons (W and Z) in a final state with one lepton, MET and HF-tagged jets, measured with the complete CDF II dataset (9.4fb^-1 of data). The signals, both ... More
Smoothing estimates for variable coefficients Schroedinger equation with electromagnetic potentialsJun 22 2012In this paper we develop the classical multiplier technique to prove a virial identity and smoothing estimates (in a perturbative setting) for the electromagnetic variable coefficients Schroedinger equation.
A duality relation for matrix pencils with application to linearizationsOct 17 2011The aim of this paper is twofold. First, we introduce a new class of linearizations, based on the generalization of a construction used in polynomial algebra to find the zeros of a system of (scalar) polynomial equations. We show that one specific linearization ... More
Theorems A and B for dagger quasi-Stein spacesFeb 13 2016In this article we use the homological methods of the theory of quasi-abelian categories and some results from functional analysis to prove Theorems A and B for (a broad sub-class of) dagger quasi-Stein spaces. In particular we show how to deduce these ... More
Game Semantics and the Geometry of Backtracking: a New Complexity Analysis of InteractionNov 19 2015Aug 11 2016We present abstract complexity results about Coquand and Hyland-Ong game semantics, that will lead to new bounds on the length of first-order cut-elimination, normalization, interaction between expansion trees and any other dialogical process game semantics ... More
The basepoint-freeness threshold and syzygies of abelian varietiesFeb 20 2019We show how a natural constant introduced by Jiang and Pareschi for a polarized abelian variety encodes information about the syzygies of the section ring of the polarization. As a particular case this gives a quick and characteristic-free proof of Lazarsfeld's ... More
BRTSim, a general-purpose computational solver for hydrological, biogeochemical, and ecosystem dynamicsMar 17 2019This paper introduces the recent release v3.1a of BRTSim (BioReactive Transport Simulator), a general-purpose multiphase and multi-species liquid, gas and heat flow solver for reaction-advection-dispersion processes in porous and non-porous media with ... More
Quantitative comparisons between finitary posterior distributions and Bayesian posterior distributionsJul 08 2008The main object of Bayesian statistical inference is the determination of posterior distributions. Sometimes these laws are given for quantities devoid of empirical value. This serious drawback vanishes when one confines oneself to considering a finite ... More
Universality in Two-Dimensional Enhancement PercolationDec 20 2007We consider a type of dependent percolation introduced by Aizenman and Grimmett, who showed that certain "enhancements" of independent (Bernoulli) percolation, called essential, make the percolation critical probability strictly smaller. In this paper ... More
Groups satisfying Kaplansky's stable finiteness conjectureJan 13 2015We prove that every {finitely generated residually finite}-by-sofic group satisfies Kaplansky's direct and stable finiteness conjectures with respect to all noetherian rings. We use this result to provide countably many new examples of finitely presented ... More
Residual properties of free productsMay 01 2014Jan 13 2015Let C be a class of groups. We give sufficient conditions ensuring that a free product of residually C groups is again residually C, and analogous conditions are given for locally embeddable into C groups. As a corollary, we obtain that the class of residually ... More
Computing the Tutte polynomial of a hyperplane arrangementSep 13 2004We define and study the Tutte polynomial of a hyperplane arrangement. We introduce a method for computing it by solving an enumerative problem in a finite field. For specific arrangements, the computation of Tutte polynomials is then reduced to certain ... More
Discrete fundamental groups of Warped Cones and expandersOct 13 2017Oct 25 2018In this paper we compute the discrete fundamental groups of warped cones. As an immediate consequence, this allows us to show that there exist coarsely simply-connected expanders and superexpanders. This also provides a strong coarse invariant of warped ... More
A sum-shuffle formula for zeta values in Tate algebrasSep 28 2016We prove a sum-shuffle formula for double zeta values in Tate algebras. This follows from an analog result for double twisted power sums, implying that an F\_p-vector space generated by multiple zeta values in Tate algebras is an F\_p-algebra.
A tropical morphism related to the hyperplane arrangement of the complete bipartite graphApr 16 2004We undertake a combinatorial study of the piecewise linear map g : R^{2m+2n} --> R^{mn} which assigns to the four vectors a, A in R^m and b, B in R^n the m by n matrix given by g_{ij} = min (a_i + b_j, A_i+B_j). This map arises naturally in Pachter and ... More
The Escaramujo Project: instrumentation courses during a road trip across the AmericasNov 18 2016The Escaramujo Project was a series of eight hands-on laboratory courses on High Energy Physics and Astroparticle Instrumentation, in Latinamerican Institutions. The Physicist Federico Izraelevitch traveled on a van with his wife and dogs from Chicago ... More
Quantum degrees of freedom of a region of spacetimeNov 29 2005The holographic principle and the thermodynamics of de Sitter space suggest that the total number of fundamental degrees of freedom associated with any finite-volume region of space may be finite. The naive picture of a short distance cut-off, however, ... More
Logic, Geometry And Probability TheoryNov 29 2013We discuss the relationship between logic, geometry and probability theory under the light of a novel approach to quantum probabilities which generalizes the method developed by R. T. Cox to the quantum logical approach to physical theories.
Toward particle-level filtering of individual collision events at the Large Hadron Collider and beyondNov 05 2013Dec 19 2014Low-energy strong interactions are a major source of background at hadron colliders, and methods of subtracting the associated energy flow are well established in the field. Traditional approaches treat the contamination as diffuse, and estimate background ... More
The cubic nonlinear Dirac equationJan 29 2013We present some results obtained in collaboration with prof. Piero D'Ancona concerning global existence for the 3D cubic non linear massless Dirac equation with a potential for small initial data in $H^1$ with slight additional assumptions. The new crucial ... More
The LHCb UpgradeOct 01 2013The LHCb experiment is designed to perform high-precision measurements of CP violation and search for New Physics using the enormous flux involving beauty and charm quarks produced at the LHC. The operation and the results obtained from the data collected ... More
Functorial resolution of tame quotient singularities in positive characteristicNov 02 2015The object of the present is a proof of the existence of functorial resolution of tame quotient singularities for quasi-projective varieties over algebraically closed fields.
On the generalized Carlitz moduleOct 09 2012Oct 16 2012The aim of this note is to gather formal similarities between two apparently different functions; {\em Euler's function} $\Gamma$ and {\em Anderson-Thakur function} $\omega$. We discuss these similarities in the framework of the {\em generalized Carlitz's ... More
Introduction aux formes modulaires de Hilbert et a leur proprietes differentiellesJul 22 2004An elementary introduction to Hilbert modular forms, with a particular attention to their differential properties: Rankin-Cohen brakets, structure of differential rings... This text will appear in SMF Seminaires et Congres.
Fundamental groups as limits of discrete fundamental groupsOct 19 2017Jun 18 2018In this note we investigate to what extent the fundamental group of a metric space can be described as the inverse limit of its discrete fundamental groups. We show that some mild conditions suffice to imply the existence of an isomorphism and we provide ... More
The Catalan matroidSep 25 2002We show how the set of Dyck paths of length 2n naturally gives rise to a matroid, which we call the "Catalan matroid" C_n. We describe this matroid in detail; among several other results, we show that C_n is self-dual, it is representable over the rationals ... More
Scaling Limits of Two-Dimensional Percolation: an OverviewOct 06 2008We present a review of the recent progress on percolation scaling limits in two dimensions. In particular, we will consider the convergence of critical crossing probabilities to Cardy's formula and of the critical exploration path to chordal SLE(6), the ... More
Isotrivial unfoldings and structural theorems for foliations on Projective spacesFeb 02 2015Nov 19 2015Following T. Suwa, we study unfoldings of algebraic foliations and their relationship with families of foliations, making focus on those unfoldings related to trivial families. The results obtained in the study of unfoldings are then applied to obtain ... More
Scaling Limit and Critical Exponents for Two-Dimensional Bootstrap PercolationOct 21 2004Consider a cellular automaton with state space $\{0,1 \}^{{\mathbb Z}^2}$ where the initial configuration $\omega_0$ is chosen according to a Bernoulli product measure, 1's are stable, and 0's become 1's if they are surrounded by at least three neighboring ... More
Free resolutions of orbit closures for the representations associated to gradings on Lie algebras of type $E_6$, $F_4$ and $G_2$Oct 24 2012Mar 14 2014The irreducible representations of complex semisimple algebraic groups with finitely many orbits are parametrized by graded simple Lie algebras. For the exceptional Lie algebras, Kraskiewicz and Weyman exhibit the Hilbert polynomials and the expected ... More
Propagating weights of tori along free resolutionsJun 07 2014May 09 2015The action of a torus on a graded module over a polynomial ring extends to the entire minimal free resolution of the module. We explain how to determine the action of the torus on the free modules in the resolution, when the resolution can be calculated ... More
Transversal and cotransversal matroids via the Lindstrom lemmaMay 23 2006It is known that the duals of transversal matroids are precisely the strict gammoids. The purpose of this short note is to show how the Lindstrom-Gessel-Viennot lemma gives a simple proof of this result.
Learning, Realizability and Games in Classical ArithmeticDec 22 2010Jun 02 2011In this dissertation we provide mathematical evidence that the concept of learning can be used to give a new and intuitive computational semantics of classical proofs in various fragments of Predicative Arithmetic. First, we extend Kreisel modified realizability ... More
On the arithmetic properties of complex values of Hecke-Mahler seriesJul 22 2004Here we characterise in a complete and explicit way the relations of algebraic dependence over $\QQ$ of complex values of Hecke-Mahler series taken at algebraic points of the multiplicative group $\GG_m^2(\CC)$. Our result contains previous theorems by ... More
Non-Locality and Theories of CausationNov 05 2001The aim of the paper is to investigate the characterization of an unambiguous notion of causation linking single space-llike separated events in EPR-Bell frameworks. This issue is investigated in ordinary quantum mechanics, with some hints to no collapse ... More
Interactive Learning Based Realizability and 1-Backtracking GamesJan 28 2011We prove that interactive learning based classical realizability (introduced by Aschieri and Berardi for first order arithmetic) is sound with respect to Coquand game semantics. In particular, any realizer of an implication-and-negation-free arithmetical ... More
Gauss-Codazzi thermodynamics on the timelike screenMay 27 2010Oct 25 2010It is a known result by Jacobson that the flux of energy-matter through a local Rindler horizon is related with the expansion of the null generators in a way that mirrors the first law of thermodynamics. We extend such a result to a timelike screen of ... More
The Role of Incentives for Opening Monopoly Markets: Comparing GTE and BOC Cooperation with Local EntrantsSep 06 2001While the 1996 Telecommunications Act requires all incumbent local telephone companies to cooperate with local entrants, section 271 of the Act provides the Bell companies (but not GTE) additional incentives to cooperate. Using an original data set, I ... More
A note on certain representations in characteristic p and associated functionsMar 25 2016May 26 2016We discuss certain representations of GL 2 Fq[T] in equal characteristic and associated vectorial modular forms
Large deviations, condensation, and giant response in a statistical systemMay 05 2015Sep 25 2015We study the probability distribution $P$ of the sum of a large number of non-identically distributed random variables $n_m$. Condensation of fluctuations, the phenomenon whereby one of such variables provides a macroscopic contribution to the global ... More
Prehomogeneous tensor spacesJun 23 2016Jun 27 2016We refine the classification of prehomogeneous vector spaces, provided by Sato-Kimura, in the case of tensor spaces, presenting a quick way to check whether a given tensor space is prehomogeneous or not.
The inner regions of disk galaxies: a constant baryonic fraction?Jun 19 2014For disk galaxies (spirals and irregulars), the inner circular-velocity gradient (inner steepness of the rotation curve) correlates with the central surface brightness with a slope of ~0.5. This implies that the central dynamical mass density scales almost ... More
Frequency Transient of Three-Dimensional Perturbations in Shear Flows. Similarity Properties and Wave Packets Linear FormationApr 12 2013Jun 27 2013The present thesis deals with the non-modal linear analysis of 3D perturbations in wall flows. In the first part,a solution to the Orr-Sommerfeld and Squire IVP, in the form of orthogonal functions expansion, is researched. The Galerkin method is successfully ... More
A sampling algorithm to estimate the effect of fluctuations in particle physics dataMay 26 2012Dec 19 2014Background properties in experimental particle physics are typically estimated using large data sets. However, different events can exhibit different features because of the quantum mechanical nature of the underlying physics processes. While signal and ... More
Constructions of General Covering DesignsMay 22 2012Dec 20 2012Given five positive integers $v, m,k,\lambda$ and $t$ where $v \geq k \geq t$ and $v \geq m \geq t,$ a $t$-$(v,k,m,\lambda)$ general covering design is a pair $(X,\mathcal{B})$ where $X$ is a set of $v$ elements (called points) and $\mathcal{B}$ a multiset ... More
tau-recurrent sequences and modular formsMay 29 2011Jun 24 2011In this paper we deal with Drinfeld modular forms, defined and taking values in complete fields of positive characteristic. Our aim is to study a sequence of families of Drinfeld modular forms depending on a parameter t that produces, for certain values ... More
CP Violation and K0 decays revelation: study and simulation of neutral Trigger in NA48 experiment -- Violazione di CP e rivelazione dei decadimenti del K0: studio e simulazione del Trigger neutro nell'esperimento NA48Jan 15 2007At the INFN laboratory in Pisa I have prepared my dissertation, which essentially concerned Montecarlo simulation of subnuclear particles decays and investigation of low-noise electronic devices for analyzing high-frequency signals. The team-work was ... More
Local solvability of a class of degenerate second order operatorsSep 27 2017In this paper we will first present some results about the local solvability property of a class of degenerate second order linear partial differential operators with smooth coefficients. The class under consideration (which in turn is a generalization ... More
Off-Criticality and the Massive Brownian Loop SoupSep 24 2013Feb 11 2016We introduce a natural "massive" version of the Brownian loop soup of Lawler and Werner which displays conformal covariance and exponential decay. We show that this massive Brownian loop soup arises as the near-critical scaling limit of a random walk ... More
Ideaux stables dans certains anneaux differentiels de formes quasi-modulaires de HilbertJul 22 2004Nesterenko proved, among other results, the algebraic independence over $\QQ$ of the numbers $\pi,e^{\pi},\Gamma(1/4)$. A very important feature of his proof is a multiplicity estimate for quasi-modular forms associated to $\SL_2(\ZZ)$ which involves ... More
Constructing matrix geometric meansJun 17 2009Jul 24 2010In this paper, we analyze the process of "assembling" new matrix geometric means from existing ones, through function composition or limit processes. We show that for n=4 a new matrix mean exists which is simpler to compute than the existing ones. Moreover, ... More
Semimatroids and their Tutte polynomialsAug 31 2004We define and study "semimatroids", a class of objects which abstracts the dependence properties of an affine hyperplane arrangement. We show that geometric semilattices are precisely the posets of flats of semimatroids. We define and investigate the ... More
A priori positivity of solutions to a non-conservative stochastic thin-film equationNov 19 2018Stochastic conservation laws are often challenging when it comes to proving existence of non-negative solutions. In a recent work by J. Fischer and G. Gr\"un (2018, Existence of positive solutions to stochastic thin-film equations, SIAM J. Math. Anal.), ... More
A note on the O(n)-storage implementation of the GKO algorithmMar 26 2009Dec 01 2009We propose a new O(n)-space implementation of the GKO-Cauchy algorithm for the solution of linear systems with Cauchy-like matrix. Despite its slightly higher computational cost, this new algorithm makes a more efficient use of the processor cache memory. ... More
On the ideal generated by all squarefree monomials of a given degreeSep 21 2016Oct 24 2017An explicit construction is given of a minimal free resolution of the ideal generated by all squarefree monomials of a given degree. The construction relies upon and exhibits the natural action of the symmetric group on the syzygy modules. The resolution ... More
Non-local Realistic Theories and the Scope of the Bell TheoremNov 18 2008According to a widespread view, the Bell theorem establishes the untenability of so-called 'local realism'. On the basis of this view, recent proposals by Leggett, Zeilinger and others have been developed according to which it can be proved that even ... More
Virial identity and dispersive estimates for the $n$-dimensional Dirac equationMar 01 2011May 17 2011We extend to general dimension $n\ge1$ the virial identity proved by Boussaid-D'Ancona-Fanelli for the 3D magnetic Dirac equation. As an application we deduce smoothing and Strichartz estimates for an $n$-dimensional Dirac equation perturbed with a magnetic ... More