Results for "Michele Di Fraia"

total 11862took 0.14s
Impulsive laser-induced alignment of OCS molecules at FERMIAug 22 2018Aug 24 2018We demonstrate the experimental realization of impulsive alignment of carbonyl sulfide (OCS) molecules at the Low Density Matter Beamline (LDM) at the free-electron laser FERMI. OCS molecules in a molecular beam were impulsively aligned using 200 fs pulses ... More
Deep neural networks for classifying complex features in diffraction imagesMar 07 2019Intense short-wavelength pulses from free-electron lasers and high-harmonic-generation sources enable diffractive imaging of individual nano-sized objects with a single x-ray laser shot. The enormous data sets with up to several million diffraction patterns ... More
Three-Dimensional Shapes of Spinning Helium NanodropletsFeb 28 2018Dec 21 2018A significant fraction of superfluid helium nanodroplets produced in a free-jet expansion have been observed to gain high angular momentum resulting in large centrifugal deformation. We measured single-shot diffraction patterns of individual rotating ... More
High-repetition-rate and high-photon-flux 70 eV high-harmonic source for coincidence ion imaging of gas-phase moleculesFeb 11 2016Apr 28 2016Unraveling and controlling chemical dynamics requires techniques to image structural changes of molecules with femtosecond temporal and picometer spatial resolution. Ultrashort-pulse x-ray free-electron lasers have significantly advanced the field by ... More
Examples of exponential instability for elliptic inverse problemsMar 11 2003Following a recent paper by N. Mandache (Inverse Problems 17 (2001), pp. 1435-1444), we establish a general procedure for determining the instability character of inverse problems. We apply this procedure to many elliptic inverse problems concerning the ... More
High-loop perturbative renormalization constants for Lattice QCD (II): three-loop quark currents for tree-level Symanzik improved gauge action and n_f=2 Wilson fermionsOct 18 2013Numerical Stochastic Perturbation Theory was able to get three- (and even four-) loop results for finite Lattice QCD renormalization constants. More recently, a conceptual and technical framework has been devised to tame finite size effects, which had ... More
Stable Determination of the Discontinuous Conductivity Coefficient of a Parabolic EquationApr 02 2009Oct 14 2009We deal with the problem of determining a time varying inclusion within a thermal conductor. In particular we study the continuous dependance of the inclusion from the Dirichlet-to-Neumann map. Under a priori regularity assumptions on the unknown defect ... More
Parallelizing quantum circuit synthesisJun 23 2016Oct 14 2016Quantum circuit synthesis is the process in which an arbitrary unitary operation is decomposed into a sequence of gates from a universal set, typically one which a quantum computer can implement both efficiently and fault-tolerantly. As physical implementations ... More
Programmable interactions with biomimetic DNA linkers at fluid membranes and interfacesMar 31 2019At the heart of the structured architecture and complex dynamics of biological systems are specific and timely interactions operated by biomolecules. In many instances, biomolecular agents are spatially confined to flexible lipid membranes where, among ... More
Fault tolerant resource estimation of quantum random-access memoriesFeb 04 2019Quantum random-access look-up of a string of classical bits is a necessary ingredient in several important quantum algorithms. In some cases, the cost of such quantum random-access memory (qRAM) is the limiting factor in the implementation of the algorithm. ... More
A Hybrid High-Order method for nonlinear elasticityJul 07 2017In this work we propose and analyze a novel Hybrid High-Order discretization of a class of (linear and) nonlinear elasticity models in the small deformation regime which are of common use in solid mechanics. The proposed method is valid in two and three ... More
A computational spectral approach to interest rate modelsAug 25 2015The Polynomial Chaos Expansion (PCE) technique recovers a finite second order random variable exploiting suitable linear combinations of orthogonal polynomials which are functions of a given stochas- tic quantity {\xi}, hence acting as a kind of random ... More
A geometric approach to cut-generating functionsJan 24 2017The cutting-plane approach to integer programming was initiated more that 40 years ago: Gomory introduced the corner polyhedron as a relaxation of a mixed integer set in tableau form and Balas introduced intersection cuts for the corner polyhedron. This ... More
EUV ionization of pure He nanodroplets: Mass-correlated photoelectron imaging, Penning ionization and electron energy-loss spectraMay 16 2013The ionization dynamics of pure He nanodroplets irradiated by EUV radiation is studied using Velocity-Map Imaging PhotoElectron-PhotoIon COincidence (VMI-PEPICO) spectroscopy. We present photoelectron energy spectra and angular distributions measured ... More
Critical Points for Elliptic Equations with Prescribed Boundary ConditionsNov 21 2016May 08 2017This paper concerns the existence of critical points for solutions to second order elliptic equations of the form $\nabla\cdot \sigma(x)\nabla u=0$ posed on a bounded domain $X$ with prescribed boundary conditions. In spatial dimension $n=2$, it is known ... More
A nonconforming high-order method for the Biot problem on general meshesJun 11 2015Feb 24 2016In this work, we introduce a novel algorithm for the Biot problem based on a Hybrid High-Order discretization of the mechanics and a Symmetric Weighted Interior Penalty discretization of the flow. The method has several assets, including, in particular, ... More
A low-order nonconforming method for linear elasticity on general meshesFeb 06 2019In this work we construct a low-order nonconforming approximation method for linear elasticity problems supporting general meshes and valid in two and three space dimensions. The method is obtained by hacking the Hybrid High-Order method, that requires ... More
Velocity-map imaging for emittance characterization of multiphoton-emitted electrons from a gold surfaceJul 20 2017A velocity-map-imaging spectrometer is demonstrated to characterize the normalized transverse emittance of photoemitted electron bunches. The two-dimensional (2D) projected velocity distribution images of photoemitted electrons are recorded by the detection ... More
Reverse Split RankJul 08 2014Oct 12 2014The reverse split rank of an integral polyhedron P is defined as the supremum of the split ranks of all rational polyhedra whose integer hull is P. Already in R^3 there exist polyhedra with infinite reverse split rank. We give a geometric characterization ... More
Ultrafast relaxation of photoexcited superfluid He nanodropletsMay 11 2019The relaxation of photoexcited nanosystems is a fundamental process of light-matter interaction. Depending on the couplings of the internal degrees of freedom, relaxation can be ultrafast, converting electronic energy in a few fs, or slow, if the energy ... More
Star Clusters in Pseudo-Bulges of Spiral GalaxiesSep 08 2009We present a study of the properties of the star-cluster systems around pseudo-bulges of late-type spiral galaxies using a sample of 11 galaxies with distances from 17 to 37 Mpc. Star clusters are identified from multiband HST ACS and WFPC2 imaging data ... More
Energy and water vapor transport across a simplified cloud-clear air interfaceFeb 24 2015We consider a simplified physics of the could interface where condensation, evaporation and radiation are neglected and momentum, thermal energy and water vapor transport is represented in terms of the Boussinesq model coupled to a passive scalar transport ... More
Estimating the number of receiving nodes in 802.11 networks via machine learning techniquesMay 13 2016Nowadays, most mobile devices are equipped with multiple wireless interfaces, causing an emerging research interest in device to device (D2D) communication: the idea behind the D2D paradigm is to exploit the proper interface to directly communicate with ... More
Volume and porosity thermal regulation in lipid mesophases by coupling mobile ligands to soft membranesJul 21 2014Jan 09 2015Short DNA linkers are increasingly being exploited for driving specific self-assembly of Brownian objects. DNA-functionalised colloids can assemble into ordered or amorphous materials with tailored morphology. Recently, the same approach has been applied ... More
From Fault Creep to slow and fast Earthquakes in CarbonatesJan 21 2019A major part of the seismicity striking the Mediterranean area and other regions worldwide is hosted in carbonate rocks. Recent examples are the destructive earthquakes of L'Aquila Mw 6.1 2009 and Norcia Mw 6.5 2016 in Central Italy. Surprisingly, within ... More
An Empirical Study on Learning Bug-Fixing Patches in the Wild via Neural Machine TranslationDec 20 2018Millions of open-source projects with numerous bug fixes are available in code repositories. This proliferation of software development histories can be leveraged to learn how to fix common programming bugs. To explore such a potential, we perform an ... More
On the convergence of the affine hull of the Chvátal-Gomory closuresOct 23 2012Nov 08 2012Given an integral polyhedron P and a rational polyhedron Q living in the same n-dimensional space and containing the same integer points as P, we investigate how many iterations of the Chv\'atal-Gomory closure operator have to be performed on Q to obtain ... More
Reverse Chvátal-Gomory rankNov 02 2012Sep 26 2014We introduce the reverse Chv\'atal-Gomory rank r*(P) of an integral polyhedron P, defined as the supremum of the Chv\'atal-Gomory ranks of all rational polyhedra whose integer hull is P. A well-known example in dimension two shows that there exist integral ... More
30Si Mole Fraction of a Silicon Material Highly Enriched in 28Si Determined by Instrumental Neutron Activation AnalysisJan 07 2016The latest determination of the Avogadro constant, carried out by counting the atoms in a pure silicon crystal highly enriched in 28Si, reached the target 2x10-8 relative uncertainty required for the redefinition of the kilogram based on the Planck constant. ... More
Estimating the cost of generic quantum pre-image attacks on SHA-2 and SHA-3Mar 30 2016Oct 13 2016We investigate the cost of Grover's quantum search algorithm when used in the context of pre-image attacks on the SHA-2 and SHA-3 families of hash functions. Our cost model assumes that the attack is run on a surface code based fault-tolerant quantum ... More
Numerical approximation of poroelasticity with random coefficients using Polynomial Chaos and Hybrid High-Order methodsMar 28 2019In this work, we consider the Biot problem with uncertain poroelastic coefficients. The uncertainty is modelled using a finite set of parameters with prescribed probability distribution. We present the variational formulation of the stochastic partial ... More
Estimating the cost of generic quantum pre-image attacks on SHA-2 and SHA-3Mar 30 2016We investigate the cost of Grover's quantum search algorithm when used in the context of pre-image attacks on the SHA-2 and SHA-3 families of hash functions. Our cost model assumes that the attack is run on a surface code based fault-tolerant quantum ... More
Estimating the cost of generic quantum pre-image attacks on SHA-2 and SHA-3Mar 30 2016Nov 30 2016We investigate the cost of Grover's quantum search algorithm when used in the context of pre-image attacks on the SHA-2 and SHA-3 families of hash functions. Our cost model assumes that the attack is run on a surface code based fault-tolerant quantum ... More
The Role of Optical Projection in the Analysis of Membrane FluctuationsNov 16 2015We propose a methodology to measure the mechanical properties of membranes from their fluctuations and apply this to optical microscopy measurements of giant unilamellar vesicles of lipids. We analyze the effect of the projection of thermal shape undulations ... More
Extended narrow-line region in Seyfert galaxiesOct 03 2017We present our recent results about the extended narrow-line region (ENLR) of two nearby Seyfert 2 galaxies (IC 5063 and NGC 7212) obtained by modelling the observed line profiles and spectra with composite models (photoionization+shocks) in the different ... More
Photophysics of indole upon x-ray absorptionFeb 08 2018A photofragmentation study of gas-phase indole (C$_8$H$_7$N) upon single-photon ionization at a photon energy of 420 eV is presented. Indole was primarily inner-shell ionized at its nitrogen and carbon $1s$ orbitals. Electrons and ions were measured in ... More
Deep neural networks for classifying complex features in diffraction imagesMar 07 2019Mar 12 2019Intense short-wavelength pulses from free-electron lasers and high-harmonic-generation sources enable diffractive imaging of individual nano-sized objects with a single x-ray laser shot. The enormous data sets with up to several million diffraction patterns ... More
Photophysics of indole upon x-ray absorptionFeb 08 2018Jul 19 2018A photofragmentation study of gas-phase indole (C$_8$H$_7$N) upon single-photon ionization at a photon energy of 420 eV is presented. Indole was primarily inner-shell ionized at its nitrogen and carbon $1s$ orbitals. Electrons and ions were measured in ... More
Deep neural networks for classifying complex features in diffraction imagesMar 07 2019Mar 13 2019Intense short-wavelength pulses from free-electron lasers and high-harmonic-generation sources enable diffractive imaging of individual nano-sized objects with a single x-ray laser shot. The enormous data sets with up to several million diffraction patterns ... More
Mapping the Periphery and Variability of the Magellanic CloudsDec 07 2018We propose a combination of a modified Wide-Fast-Deep survey, a mini-survey of the South Celestial Pole, and a Deep Drilling-style survey to produce a 3-D map of the Magellanic System and to provide a detailed census of the transient and variable populations ... More
Recent Results from CDFDec 06 1999We present the latest results from the CDF experiment at the Tevatron Collider in \ppbar collisions at $\sqrt{s} = 1.8$ TeV. The large data sample collected during Run 1, from 1992 until 1995, allows measurements in many domains of high-energy physics. ... More
A New Scintillator Tile/Fiber Preshower Detector for the CDF Central CalorimeterNov 05 2004Aug 19 2005A detector designed to measure early particle showers has been installed in front of the central CDF calorimeter at the Tevatron. This new preshower detector is based on scintillator tiles coupled to wavelength-shifting fibers read out by multi-anode ... More
Beyond Fisher: exact sampling distributions of the maximum-likelihood estimator in gravitational-wave parameter estimationAug 04 2011Nov 04 2011Gravitational-wave astronomers often wish to characterize the expected parameter-estimation accuracy of future observations. The Fisher matrix provides a lower bound on the spread of the maximum-likelihood estimator across noise realizations, as well ... More
Synthetic LISA: Simulating Time Delay Interferometry in a Model LISAJul 27 2004Jan 05 2005We report on three numerical experiments on the implementation of Time-Delay Interferometry (TDI) for LISA, performed with Synthetic LISA, a C++/Python package that we developed to simulate the LISA science process at the level of scientific and technical ... More
Prospects for gravitational-wave observations of neutron-star tidal disruption in neutron-star/black-hole binariesDec 08 1999Apr 19 2000For an inspiraling neutron-star/black-hole binary (NS/BH), we estimate the gravity-wave frequency f_td at the onset of NS tidal disruption. We model the NS as a tidally distorted, homogeneous, Newtonian ellipsoid on a circular, equatorial geodesic around ... More
Use and Abuse of the Fisher Information Matrix in the Assessment of Gravitational-Wave Parameter-Estimation ProspectsMar 15 2007Feb 04 2008The Fisher-matrix formalism is used routinely in the literature on gravitational-wave detection to characterize the parameter-estimation performance of gravitational-wave measurements, given parametrized models of the waveforms, and assuming detector ... More
Gutzwiller description of non-magnetic Mott insulators: a dimer lattice modelApr 11 2007We introduce a novel extension of the Gutzwiller variational wavefunction able to deal with insulators that escape any mean-field like description, as for instance non-magnetic insulators. As an application, we study the Mott transition from a paramagnetic ... More
Phase oscillator model for noisy oscillatorsMay 07 2019The Kuramoto model has become a paradigm to describe the dynamics of nonlinear oscillator under the influence of external perturbations, both deterministic and stochastic. It is based on the idea to describe the oscillator dynamics by a scalar differential ... More
Quantum Schroedinger bridgesJun 06 2003Elaborating on M. Pavon, J.Math. Phys. 40 (1999), 5565-5577, we develop a simplified version of a variational principle within Nelson stochastic mechanics that produces the von Neumann wave packet reduction after a position measurement. This stochastic ... More
The Connectedness of Space Curve InvariantsJan 28 1994It is a result of Gruson and Peskine that the invariants of a set points in $\ptwo$ in general position are connected. Associated to a space curve there are sequences of invariants which generalize the invariants of points in $\ptwo$. The main result ... More
Fluctuation Relation for Quantum Heat Engines and RefrigeratorsMar 31 2014May 23 2014At the very foundation of the second law of thermodynamics lies the fact that no heat engine operating between two reservoires of temperatures $T_C\leq T_H$ can overperform the ideal Carnot engine: $\langle W \rangle / \langle Q_H \rangle \leq 1-T_C/T_H$. ... More
Nonlinear inviscid damping for zero mean perturbation of the 2D Euler Couette flowMar 04 2019In this note we revisit the proof of Bedrossian and Masmoudi [arXiv:1306.5028] about the inviscid damping of planar shear flows in the 2D Euler equations under the assumption of zero mean perturbation. We prove that a small perturbation to the 2D Euler ... More
Critical points of random branched coverings of the Riemann sphereMay 10 2019Given a closed Riemann surface $\Sigma$ equipped with a volume form $\omega$, we construct a natural probability measure on the space $\mathcal{M}_d(\Sigma)$ of degree $d$ branched coverings from $\Sigma$ to the Riemann sphere $\mathbb{C}\mathbb{P}^1.$ ... More
Self-dual manifolds and mirror symmetry for the quintic threefoldJan 02 2003Feb 15 2003For all $m > 0$ we build a two-dimensional family of smooth manifolds of real dimension $3m + 2$ and use it to interpolate between the anticanonical family in the complex projective space of dimension $m + 1$ and its mirror dual. The main tool is the ... More
An improved bound for the degree of smooth surfaces in P4 not of general type.Jan 16 1995This is an addendum to the paper of Braun and Fl{\o}ystad ([BF]) on the bound for the degree of a smooth surface in $\pfour$ not of general type. Using their construction and the regularity of curves in $\pthree$, one may lower the bound a little more. ... More
Polysymplectic spaces, s-Kahler manifolds and lagrangian fibrationsJun 21 2000In the first part of this paper we begin the study of polysymplectic manifolds, and of their relationship with PDE's. This notion provides a generalization of symplectic manifolds which is very well suited for the geometric study of PDE's with values ... More
The LTP Experiment on LISA Pathfinder: Operational Definition of TT Gauge in SpaceOct 13 2011The European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA) are planning the Laser Interferometer Space Antenna (LISA) mission in order to detect GW. The need of accurate testing of free-fall and knowledge of noise in ... More
On a class of conserved phase field systems with a maximal monotone perturbationSep 01 2016We prove existence and regularity for the solutions to a Cahn-Hilliard system describing the phenomenon of phase separation for a material contained in a bounded and regular domain. Since the first equation of the system is perturbed by the presence of ... More
Geometric TransitionsDec 28 2004The purpose of this paper is to give, on one hand, a mathematical exposition of the main topological and geometrical properties of geometric transitions, on the other hand, a quick outline of their principal applications, both in mathematics and in physics. ... More
Généricité au sens probabiliste dans les difféomorphismes du cercleNov 19 2014Nov 27 2014What kind of dynamics do we observe in general on the circle? It depends somehow on the interpretation of "in general". Everything is quite well understood in the topological (Baire) setting, but what about the probabilistic sense? The main problem is ... More
Coherent Sheaves on Ribbons and their ModuliFeb 22 2019A ribbon is a non-reduced curve modelled on the first infinitesimal neighbourhood of a smooth curve in a surface. This paper is devoted to describe some properties of coherent sheaves on such a curve and their Simpson moduli space. In particular we give ... More
Generalized line bundles on primitive multiple curves and their moduliFeb 25 2019In this paper, we study generalized line bundles over $C_n$, a primitive multiple curve of arbitrary multiplicity $n$, where $n$ is a positive integer. In particular, we give a structure theorem for them and we characterize their semistability in terms ... More
A conic bundle degenerating on the Kummer surfaceFeb 18 2007Let $C$ be a genus 2 curve and $\su$ the moduli space of semi-stable rank 2 vector bundles on $C$ with trivial determinant. In \cite{bol:wed} we described the parameter space of non stable extension classes (invariant with respect to the hyperelliptic ... More
On Weddle Surfaces And Their ModuliJan 11 2006Oct 04 2006The Weddle surface is classically known to be a birational (partially desingularized) model of the Kummer surface. In this note we go through its relations with moduli spaces of abelian varieties and of rank two vector bundles on a genus 2 curve. First ... More
The Renormalization Group for Disordered SystemsJul 25 2013In this thesis we investigate the Renormalization Group (RG) approach in finite-dimensional glassy systems, whose critical features are still not well-established, or simply unknown. We focus on spin and structural-glass models built on hierarchical lattices, ... More
Improving the full spectrum fitting method: accurate convolution with Gauss-Hermite functionsJul 28 2016I start by providing an updated summary of the penalized pixel-fitting (pPXF) method, which is used to extract the stellar and gas kinematics, as well as the stellar population of galaxies, via full spectrum fitting. I then focus on the problem of extracting ... More
Quantum Monte Carlo study of a two dimensional dipolar Bose gas in a harmonic trapMay 26 2013Apr 07 2014We present a Quantum Monte Carlo study of the ground state properties of a two dimensional system of Bose particle with dipole moment in a harmonic trap. The direction of the dipoles is assumed to be fixed by an external field. We study how the system ... More
Geometric Time Delay InterferometryApr 29 2005Jun 28 2005The space-based gravitational-wave observatory LISA, a NASA-ESA mission to be launched after 2012, will achieve its optimal sensitivity using Time Delay Interferometry (TDI), a LISA-specific technique needed to cancel the otherwise overwhelming laser ... More
Poisson summation formula and Box splinesFeb 26 2013Mar 05 2013We generalize Dahmen-Micchelli deconvolution formula for Box splines with parameters. Our proof is based on identities for Poisson summation of rational functions with poles on hyperplanes.
Collective dynamics and expansion of a Bose-Einstein condensate in a random potentialSep 30 2005We investigate the dynamics of a Bose-Einstein condensate in the presence of a random potential created by optical speckles. We first consider the effect of a weak disorder on the dipole and quadrupole collective oscillations, finding uncorrelated frequency ... More
Prospects and synergies between future atmospheric and long-baseline experimentsOct 08 2008In this talk we will discuss the physics reach of the atmospheric neutrino data collected by a future megaton-class neutrino detector. First we will discuss the potentialities of atmospheric neutrinos on general basis, presenting our results in the form ... More
Black Hole Complementarity and the Physical Origin of the Stretched HorizonOct 23 1993We discuss the idea of black hole complementarity, recently suggested by Susskind et al., and the notion of stretched horizon, in the light of the generalized uncertainty principle of quantum gravity. We discuss implications for the no-hair theorem and ... More
The algebraic structure of the generalized uncertainty principleSep 06 1993We show that a deformation of the Heisenberg algebra which depends on a dimensionful parameter $\kappa$ is the algebraic structure which underlies the generalized uncertainty principle in quantum gravity. The deformed algebra and therefore the form of ... More
Quantum AlgorithmsAug 04 2008This article surveys the state of the art in quantum computer algorithms, including both black-box and non-black-box results. It is infeasible to detail all the known quantum algorithms, so a representative sample is given. This includes a summary of ... More
Leptogenesis in natural low-scale seesaw mechanismsOct 15 2015We explore the hypothesis of having an approximate lepton number conservation as a way to achieve a successful leptogenesis in low-scale seesaw mechanisms. The smallness of the active neutrino masses, as well as a strong degeneracy in the mass spectrum ... More
Quantum signature in classical electrodynamics of the free radiation fieldMay 20 2015Quantum optics is a field of research based on the quantum theory of light. Here, we show that the classical theory of light can be equally effective in explaining a cornerstone of quantum optics: the quantization of the free radiation field. The quantization ... More
A decade of dark matter searches with ground-based Cherenkov telescopesApr 20 2014In the general scenario of Weakly Interacting Massive Particles (WIMP), dark matter (DM) can be observed via astrophysical gamma rays because photons are produced in various DM annihilation or decay processes, either as broad-band or line emission, or ... More
Perspectives for Top quark physics at High-Luminosity LHCDec 15 2015The High-Luminosity LHC is expected to provide $3 ab^{-1}$ of integrated luminosity. As a result billions of events containing top quarks will be detected at the CMS and ATLAS experiments, allowing for precise measurements of the top quark properties. ... More
Amplitude and phase dynamics of noisy oscillatorsMar 23 2015A description in terms of phase and amplitude variables is given, for nonlinear oscillators subject to white Gaussian noise described by It\^o stochastic differential equations. The stochastic differential equations derived for the amplitude and the phase ... More
Dynamical Mass Determinations and Scaling Relations of Early-Type GalaxiesOct 27 2014I review our understanding of classic dynamical scaling relations, relating luminosity, size and kinematics of early-type galaxies. Using unbiased determinations of galaxy mass profiles from stellar dynamical models, a simple picture has emerged in which ... More
From Grad-Shafranov equations set to a pseudo-general form of the non-linear Schroedinger equationJul 10 2008In the year 2003 a paper by G. Lapenta demonstrated that there is a new class of soliton-like solutions for the Grad-Shafranov Equations (GSE).The author determined an appropriate pair of transformations of the free fields p (fluid field of hydrodynamical ... More
A New Family Symmetry: Discrete Quaternion GroupMay 16 2005We examine the structure of the quaternion group $Q_8$ and its possible application to the physics of flavor. We find that a $Q_8$ family symmetry is suitable to explain the difference between quark and lepton mixing patterns. Distinctive phenomenological ... More
Complementary expressions for the entropy-from-work theoremApr 15 2008We establish an expression of the entropy-from-work theorem that is complementary to the one originally proposed in [P. Talkner, P. Hanggi and M. Morillo, arXiv:0707.2307]. In the original expression the final energy is fixed whereas in the present expression ... More
Increase of quantum volume entropy in presence of degenerate eigenenergiesApr 07 2016The entropy of a classical thermally isolated Hamiltonian system is given by the logarithm of the measure of phase space enclosed by the constant energy hyper-surface, also known as volume entropy. It has been shown that on average the latter cannot decrease ... More
Temporal expression normalisation in natural language textsJun 10 2012Automatic annotation of temporal expressions is a research challenge of great interest in the field of information extraction. In this report, I describe a novel rule-based architecture, built on top of a pre-existing system, which is able to normalise ... More
Beyond the locality approximation in the standard diffusion Monte Carlo methodOct 09 2006We present a way to include non local potentials in the standard Diffusion Monte Carlo method without using the locality approximation. We define a stochastic projection based on a fixed node effective Hamiltonian, whose lowest energy is an upper bound ... More
On terminal Fano 3-folds with 2-torus action, part IIMar 11 2018We continue the classification of terminal Fano threefolds with an effective two-torus action. In earlier work we settled the Q-factorial case with Picard number one. Here we treat the larger class of varieties that do not admit any contraction of a prime ... More
Étale coverings in codimension 1 with applications to Mori Dream SpacesFeb 13 2019The present paper is devoted to developing relations between Galois \'etale coverings in codimension 1 and \'etale fundamental groups in codimension 1 of algebraic varieties, aimed to studying the topology of Mori dream spaces. In particular, the universal ... More
On Framed Quivers, BPS Invariants and DefectsJan 11 2018In this note we review some of the uses of framed quivers to study BPS invariants of Donaldson-Thomas type. We will mostly focus on non-compact Calabi-Yau threefolds. In certain cases the study of these invariants can be approached as a generalized instanton ... More
Cyclic presentations of groups and cyclic branched coverings of (1,1)-knotsSep 19 2001Sep 23 2002In this paper we study the connections between cyclic presentations of groups and branched cyclic coverings of (1,1)-knots. In particular, we prove that every n-fold strongly-cyclic branched covering of a (1,1)-knot admits a cyclic presentation for the ... More
A rigidity theorem for small resolutionsMar 07 2012Aug 28 2014This paper presents a rigidity property of the exceptional locus of some kind of small birational contractions. An application in the context of geometric transitions and Calabi-Yau threefolds moduli space is then given, with some physical implication ... More
Embedding non-projective Mori Dream SpacesSep 07 2018Jan 29 2019This paper is devoted to extend some Hu-Keel results on Mori dream spaces (MDS) beyond the projective setup. Namely, $\Q$-factorial algebraic varieties with finitely generated class group and Cox ring, here called \emph{weak} Mori dream spaces (wMDS), ... More
A LISA Data-Analysis PrimerDec 03 2008Feb 20 2009This article is an introduction for the nonpractitioner to the ideas and issues of LISA data analysis, as reflected in the explorations and experiments of the participants in the Mock LISA Data Challenges. In particular, I discuss the methods and codes ... More
A Remark on the Convolution with Box SplinesMar 08 2010The semi-discrete convolution with the Box Spline is an important tool in approximation theory. We give a formula for the difference between semi-discrete convolution and convolution with the Box Spline. This formula involves multiple Bernoulli polynomials. ... More
Performance of the CDF Miniplug CalorimetersDec 16 2002Two Miniplug calorimeters, designed to measure the energy and lateral position of particles in the forward pseudorapidity region of 3.6<|\eta |<5.1, have been installed as part of the CDF upgraded detector for Run II at the Tevatron. Proton-antiproton ... More
Real space Renormalization Group analysis of a non-mean field spin-glassMay 25 2011Aug 23 2011A real space Renormalization Group approach is presented for a non-mean field spin-glass. This approach has been conceived in the effort to develop an alternative method to the Renormalization Group approaches based on the replica method. Indeed, non-perturbative ... More
The Out-of-Equilibrium Time-Dependent Gutzwiller ApproximationApr 10 2012We review the recently proposed extension of the Gutzwiller approximation, M. Schiro' and M. Fabrizio, Phys. Rev. Lett. 105, 076401 (2010), designed to describe the out-of-equilibrium time-evolution of a Gutzwiller-type variational wave function for correlated ... More
Exponential localization in one-dimensional quasiperiodic optical latticesJan 02 2009We investigate the localization properties of a one-dimensional bichromatic optical lattice in the tight binding regime, by discussing how exponentially localized states emerge upon changing the degree of commensurability. We also review the mapping onto ... More
Massive string modes and non-singular pre-big-bang cosmologySep 02 1997May 02 1998Perturbative $\alpha '$ corrections to the low energy string effective action have been recently found to have a potentially regularizing effect on the singularity of the lowest order pre-big-bang solutions. Whether they actually regularize it, however, ... More
Horizon quantization and thermodynamics of the 2+1 black holeJul 14 1994We test on the 2+1 dimensional black hole the quantization method that we have previously proposed in four dimensions. While in the latter case the horizon dynamics is described, at the effective level, by the action of a relativistic membrane, in the ... More