Results for "Giacomo Prando"

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Anomalous lattice contraction and emergent electronic phases in Bi-doped Eu$_2$Ir$_2$O$_7$Feb 08 2019We study the pyrochlore series (Eu$_{1-x}$Bi$_x$)$_2$Ir$_2$O$_7$ for $ 0 \leq x \leq 1$. We show that for small $x$, the lattice undergoes an anomalous contraction but the all-in/all-out and metal-to-insulator transitions remain robust, and the resistivity ... More
Effects of quantum impurity spins on the magnetic properties of zigzag and linear spin chainsFeb 11 2016We investigated the magnetic ground state and low-energy excitations of the spin chains compounds SrCuO$_{2}$ (zigzag chains) and Sr$_{2}$CuO$_{3}$ (linear chains) in the presence of quantum impurities induced by lightly doping ($\leq 1 \%$) with Zn$^{2+}$ ... More
The construction and commissioning of the CMS Silicon Strip TrackerSep 19 2008Oct 06 2008As the start up date for LHC approaches, the detectors are readying for data taking. Here a review will be given on the construction phase with insights into the various difficulties encountered during the process. An overview will also be given of the ... More
Bayesian complementary clustering, MCMC and Anglo-Saxon placenamesSep 24 2014Jul 02 2015Common cluster models for multi-type point processes model the aggregation of points of the same type. In complete contrast, in the study of Anglo-Saxon settlements it is hypothesized that administrative clusters involving complementary names tend to ... More
The topologies of Supersymmetry signals at LEPSep 12 2002The topologies arising from the production of supersymmetric particles at the LEP collider are briefly reviewed recalling detector requirements, simulation and other experimental issues.
An Unexpected Effect in ALEPH: Long-Term Displacements of the Silicon Vertex DetectorMay 16 2002The ALEPH Silicon Vertex Detector for LEP2 featured a laser survey system to monitor its mechanical stability. The analysis of laser system data from 1997 to 2000 showed that VDET suffered a time-dependent displacement. It resulted to be compatible with ... More
Sinusoidal Gravitational Waves from the Nuclei of Active GalaxiesMay 26 1993It is believed that most quasars and galaxies present two common features: the presence in their core of a supermassive object, and the experience of one or more encounters with other galaxies. In this scenario, it is likely that a substantial fraction ... More
Generation of discrete random variables in scalable frameworkNov 21 2016In this paper, we face the problem of simulating discrete random variables with general and varying distribution in a scalable framework, where fully parallelizable operations should be preferred. Compared with classical algorithms, we add randomness, ... More
Almost periodic functions and hyperbolic countingOct 19 2016Nov 22 2018In this paper we prove the existence of asymptotic moments, and an estimate on the tails of the limiting distribution, for a specific class of almost periodic functions. Then we introduce the hyperbolic circle problem, proving an estimate on the asymptotic ... More
Constructions of Locally Recoverable Codes which are OptimalJun 29 2018We provide a Galois theoretical framework which allows to produce good polynomials for the Tamo and Barg construction of optimal locally recoverable codes (LRC). Our approach allows to prove existence results and to construct new good polynomials, which ... More
Line defects in the small elastic constant limit of a three-dimensional Landau-de Gennes modelJan 21 2015Apr 16 2016We consider the Landau-de Gennes variational model for nematic liquid crystals, in three-dimensional domains. More precisely, we study the asymptotic behaviour of minimizers as the elastic constant tends to zero, under the assumption that minimizers are ... More
Classical vs. Bayesian methods for linear system identification: point estimators and confidence setsJul 02 2015This paper compares classical parametric methods with recently developed Bayesian methods for system identification. A Full Bayes solution is considered together with one of the standard approximations based on the Empirical Bayes paradigm. Results regarding ... More
Precision Electroweak Physics and Higgsless Models in Warped SpaceSep 14 2004We study tree level corrections to precision electroweak physics in the recently proposed Higgsless models in warped space. Such models inherit from their similarity with technicolor theories a large contribution to the oblique parameters, S in particular. ... More
SUSY Particles Searches at LEP and Interpretations within the MSSMOct 08 2002Searches for R-parity conserving supersymmetric particles have been performed in e+e- data collected by LEP detectors, at centre-of-mass energies up to 209GeV, corresponding to an integrated luminosity of 3.1fb-1. The results and their interpretation ... More
The Construction of the CMS Silicon Strip TrackerJan 16 2008The CMS Silicon Strip tracker is a very large scale tracker entirely based on silicon strip detectors technology. The integration of modules, electronics, mechanics and services has been completed within the last eighteen months; first large standalone ... More
An Introduction to Quantum Computing, Without the PhysicsAug 11 2017Nov 19 2018This paper is a gentle but rigorous introduction to quantum computing intended for discrete mathematicians. Starting from a small set of assumptions on the behavior of quantum computing devices, we analyze their main characteristics, stressing the differences ... More
Compressing redundant information in Markov chainsMay 03 2006Jun 23 2006Given a strongly stationary Markov chain and a finite set of stopping rules, we prove the existence of a polynomial algorithm which projects the Markov chain onto a minimal Markov chain without redundant information. Markov complexity is hence defined ... More
Biaxiality in the asymptotic analysis of a 2-D Landau-de Gennes model for liquid crystalsJul 30 2013Jan 08 2014We consider the Landau-de Gennes variational problem on a bound\-ed, two dimensional domain, subject to Dirichlet smooth boundary conditions. We prove that minimizers are maximally biaxial near the singularities, that is, their biaxiality parameter reaches ... More
CMS Inner Tracker Detector ModulesNov 06 2004The production of silicon detector modules that will instrument the CMS Inner Tracker has nowadays reached 1300 units out of the approximately 3700 needed in total, with an overall yield close to 96%. A description of the module design, the assembly procedures ... More
The CMS Si-strip TrackerFeb 03 2004The Compact Muon Solenoid (CMS) experiment at LHC features the largest Silicon Strip Tracker (SST) ever build. This device is immersed in a 4T magnetic field and, in conjunction with a Pixel system, it allows the momentum of the charged particles to be ... More
Almost periodic functions and hyperbolic countingOct 19 2016In this paper we prove the existence of asymptotic moments, and an estimate on the tails of the limiting distribution, for a specific class of almost periodic functions. Then we introduce the hyperbolic circle problem, proving an estimate on the asymptotic ... More
A frequency approach to topological identification and graphical modelingAug 07 2011This works explores and illustrates recent results developed by the author in field of dynamical network analysis. The considered approach is blind, i.e., no a priori assumptions on the interconnected systems are available. Moreover, the perspective is ... More
Observations of Gamma-ray Bursts in the Fermi eraApr 20 2013May 23 2013The Fermi observatory, with its Gamma-Ray Bursts monitor (GBM) and Large Area Telescope (LAT), is observing Gamma-ray Bursts with unprecedented spectral coverage and sensitivity, from ~10 keV to > 300 GeV. In the first 3 years of the mission it observed ... More
Generation of discrete random variables in scalable frameworksNov 21 2016Jul 10 2017In this paper, we face the problem of simulating discrete random variables with general and varying distributions in a scalable framework, where fully parallelizable operations should be preferred. The new paradigm is inspired by the context of discrete ... More
Game Theory (Open Access textbook with 165 solved exercises)Dec 21 2015This is an Open Access textbook on non-cooperative Game Theory with 165 solved exercises.
Performance of hybrid quantum/classical variational heuristics for combinatorial optimizationMay 30 2018Dec 13 2018The recent literature on near-term applications for quantum computers contains several examples of the applications of hybrid quantum/classical variational approaches. This methodology can be applied to a variety of optimization problems, but its practical ... More
The Moment Guided Monte Carlo method for the Boltzmann equationJul 04 2012Jul 09 2013In this work we propose a generalization of the Moment Guided Monte Carlo method developed in [11]. This approach permits to reduce the variance of the particle methods through a matching with a set of suitable macroscopic moment equations. In order to ... More
On the selection of polynomials for the DLP quasi-polynomial time algorithm in small characteristicJun 26 2017Feb 28 2019In this paper we characterize the set of polynomials $f\in\mathbb F_q[X]$ satisfying the following property: there exists a positive integer $d$ such that for any positive integer $\ell$ less or equal than the degree of $f$, there exists $t_0$ in $\mathbb ... More
Higgs and Beyond Standard Model Searches at LEPNov 06 2004Extensive searches for Higgs bosons and other new phenomena predicted by extensions of the Standard Model have been performed at LEP. A summary is given reviewing the principal aspects and presenting a selection of results.
Relativity Experiments in the Solar SystemApr 27 1995Recent theoretical works on alternative metric theories of gravity give greater significance to solar-system tests of General Relativity. In particular, it is suggested that the post-Newtonian parameter $\gamma$ ought to be determined with great precision ... More
Cryptanalysis of a non-commutative key exchange protocolJun 22 2013In the papers by Alvarez et al. and Pathak and Sanghi a non-commutative based public key exchange is described. A similiar version of it has also been patented (US7184551). In this paper we present a polynomial time attack that breaks the variants of ... More
Epitopological and pseudotopological fundamental group functorsJul 18 2017In these notes the epitopological and pseudotopological fundamental group functors are introduced. These are functors from the category of pointed epitopological and pseudotopological spaces respectively, to the category of their respective group-objects. ... More
Sylvester's law of inertia for quadratic forms on vector bundlesJul 08 2013Aug 06 2013This paper presents a generalisation of Sylvester's law of inertia to real non-degenerate quadratic forms on a fixed real vector bundle over a connected locally connected paracompact Hausdorff space. By interpreting the classical inertia as a complete ... More
Results from cosmics and first LHC beam with the ALICE HMPID detectorJul 27 2009Sep 21 2009The ALICE HMPID (High Momentum Particle IDentification) detector has been designed to identify charged pions and kaons in the range 1 < p < 3 GeV/c and protons in the range 1.5 < p < 5 GeV/c. It consists of seven identical proximity focusing RICH (Ring ... More
Gravitational Waves from a Population of Galactic Neutron StarsJan 05 1998The existence of a large number of asymmetric, rotating neutron stars, each individually emitting periodic or quasi-periodic gravitational waves in the frequency band around 100 Hz, raises the possibility of detecting their combined signals, by exploiting ... More
Induced paramagnetic states by localized $π$-loops in grain boundariesMar 11 2003Recent experiments on high-temperature superconductors show paramagnetic behavior localized at grain boundaries (GB). This paramagnetism can be attributed to the presence unconventional d-wave induced $\pi$-junctions. By modeling the GB as an array of ... More
Massive binary star mergers in galactic nuclei: implications for blue stragglers, binary S-stars and gravitational wavesMar 07 2019Most of the stars are believed to be born in binaries or higher-multiplicity systems. The implications of the presence of a binary population in galactic nuclei have been under scrutiny only recently. Observations suggest that our Galactic Centre harbours ... More
Nbd is not cartesian closedJul 19 2017In this short note it is shown that the category of neighborhood spaces is not cartesian closed.
The emergence of the concept of filter in topological categoriesJul 19 2017In all approaches to convergence where the concept of filter is taken as primary, the usual motivation is the notion of neighborhood filter in a topological space. However, these approaches often lead to spaces more general than topological ones, thereby ... More
Effect of external pressure on the magnetic properties of LnFeAsO (Ln = La, Ce, Pr, Sm)May 11 2012We investigate the effect of external pressure on magnetic order in undoped LnFeAsO (Ln = La, Ce, Pr, La) by using muon-spin relaxation measurements and ab-initio calculations. Both magnetic transition temperature $T_m$ and Fe magnetic moment decrease ... More
Magnetic properties of spin diluted iron pnictides from muSR and NMR in LaFe1-xRuxAsOOct 21 2011The effect of isoelectronic substitutions on the microscopic properties of LaFe1-xRuxAsO, for 0< x< 0.8, has been investigated by means of muSR and 139La NMR. It was found that Ru substitution causes a progressive reduction of the N\`eel temperature (T_N) ... More
Direct evidence for the emergence of a pressure induced nodal superconducting gap in the iron-based superconductor Ba_0.65Rb_0.35Fe_2As_2May 05 2015Identifying the superconducting (SC) gap structure of the iron-based high-temperature superconductors (Fe-HTS's) remains a key issue for the understanding of superconductivity in these materials. In contrast to other unconventional superconductors, in ... More
AC susceptibility investigation of vortex dynamics in nearly-optimally doped REFeAsO$_{1-x}$F$_{x}$ superconductors (RE = La, Ce, Sm)Dec 30 2011Ac susceptibility and static magnetization measurements were performed in the nearly-optimally doped LaFeAsO$_{0.9}$F$_{0.1}$ and CeFeAsO$_{0.92}$F$_{0.08}$ superconductors, complementing earlier results on SmFeAsO$_{0.8}$F$_{0.2}$ [Phys. Rev. {\bf B ... More
Amorphous ferromagnetism and re-entrant magnetic glassiness in Sm$_{2}$Mo$_{2}$O$_{7}$: new insights into the electronic phase diagram of pyrochlore molybdatesMay 26 2014We discuss the magnetic properties of a Sm$_{2}$Mo$_{2}$O$_{7}$ single crystal as investigated by means of different experimental techniques. In the literature, a conventional itinerant ferromagnetic state is reported for the Mo$^{4+}$ sublattice below ... More
Implicit-Explicit multistep methods for hyperbolic systems with multiscale relaxationApr 08 2019We consider the development of high order space and time numerical methods based on Implicit-Explicit (IMEX) multistep time integrators for hyperbolic systems with relaxation. More specifically, we consider hyperbolic balance laws in which the convection ... More
An Ultraviolet Chiral Theory of the Top for the Fundamental Composite (Goldstone) HiggsJul 31 2015Feb 24 2016We introduce a scalar-less anomaly free chiral gauge theory that serves as natural ultraviolet completion of models of fundamental composite (Goldstone) Higgs dynamics. The new theory is able to generate the top mass and furthermore features a built-in ... More
Is F-term hybrid inflation natural within minimal supersymmetric SO(10)?Jun 13 2013We examine whether F-term supersymmetric hybrid inflation can be embedded within the minimal SO(10) model, in a natural way. We show that none of the singlets of the Standard Model symmetries in the minimal set of SO(10) representations can satisfy the ... More
On Canonical Subfield Preserving PolynomialsSep 25 2013Jul 31 2014Explicit monoid structure is provided for the class of canonical subfield preserving polynomials over finite fields. Some classical results and asymptotic estimates will follow as corollaries.
Physics as Quantum Information Processing: Quantum Fields as Quantum AutomataOct 31 2011Dec 20 2011Can we reduce Quantum Field Theory (QFT) to a quantum computation? Can physics be simulated by a quantum computer? Do we believe that a quantum field is ultimately made of a numerable set of quantum systems that are unitarily interacting? A positive answer ... More
Physics as quantum information processingDec 12 2010The experience from Quantum Information has lead us to look at Quantum Theory (QT) and the whole Physics from a different angle. The information-theoretical paradigm---"It from Bit'---prophesied by John Archibald Wheeler is relentlessly advancing. Recently ... More
The Quantum Field as a Quantum ComputerDec 02 2010It is supposed that at very small scales a quantum field is an infinite homogeneous quantum computer. On a quantum computer the information cannot propagate faster than $c=a/\tau$, $a$ and $\tau$ being the minimum space and time distances between gates, ... More
Probabilistic theories: what is special about Quantum Mechanics?Jul 28 2008Apr 16 2009Quantum Mechanics (QM) is a very special probabilistic theory, yet we don't know which operational principles make it so. All axiomatization attempts suffer at least one postulate of a mathematical nature. Here I will analyze the possibility of deriving ... More
On Minimal Spectral Factors with Zeroes and Poles lying on Prescribed RegionJun 02 2015Sep 25 2015In this paper, we consider a general discrete-time spectral factorization problem for rational matrix-valued functions. We build on a recent result establishing existence of a spectral factor whose zeroes and poles lie in any pair of prescribed regions ... More
On the Factorization of Rational Discrete-Time Spectral DensitiesOct 03 2014Jun 02 2015In this paper, we consider an arbitrary matrix-valued, rational spectral density $\Phi(z)$. We show with a constructive proof that $\Phi(z)$ admits a factorization of the form $\Phi(z)=W^\top (z^{-1})W(z)$, where $W(z)$ is stochastically minimal. Moreover, ... More
Minimal model of financial stylized factsNov 27 2010Mar 09 2011In this work we afford the statistical characterization of a linear Stochastic Volatility Model featuring Inverse Gamma stationary distribution for the instantaneous volatility. We detail the derivation of the moments of the return distribution, revealing ... More
Multivariate trend-cycle extraction with the Hodrick-Prescott filterAug 23 2015The Hodrick-Prescott filter represents one of the most popular method for trend-cycle extraction in macroeconomic time series. In this paper we provide a multivariate generalization of the Hodrick-Prescott filter, based on the seemingly unrelated time ... More
Black hole-neutron star mergers from triplesMar 25 2019Mergers of black hole (BH) and neutron star (NS) binaries are expected to be observed by gravitational wave observatories in the coming years. Until now, LIGO has only set an upper limit on this merger rate. BH-NS binaries are expected to merge in isolation, ... More
Eccentric binary black hole mergers in globular clusters hosting intermediate-mass black holesMar 22 2019Globular clusters (GCs) may harbour intermediate-mass black holes (IMBHs) at their centres. In these dynamically active environments stellar-mass black holes (SBHs) sink to the center soon after formation, due to dynamical friction and start interacting ... More
Self-compensation due to point defects in Mg-doped GaNJul 28 2016Using hybrid density functional theory, we address point defects susceptible to cause charge compensation upon Mg doping of GaN. We determine the free energy of formation of the nitrogen vacancy and of several Mg-related defects. The entropic contribution ... More
Monolithic coupling of implicit material point method with finite element methodNov 27 2018A monolithic coupling between the material point method (MPM) and the finite element method (FEM) is presented. The MPM formulation described is implicit, and the exchange of information between particles and background grid is minimized. The reduced ... More
Kinetic modeling of alcohol consumptionFeb 21 2019In most countries, alcohol consumption distributions have been shown to possess universal features. Their unimodal right-skewed shape is usually modeled in terms of the Lognormal distribution, which is easy to fit, test, and modify. However, empirical ... More
Implicit-explicit linear multistep methods for stiff kinetic equationsMar 01 2016We consider the development of high order asymptotic-preserving linear multistep methods for kinetic equations and related problems. The methods are first developed for BGK-like kinetic models and then extended to the case of the full Boltzmann equation. ... More
Full Classification of permutation rational functions and complete rational functions of degree three over finite fieldsMay 08 2018Feb 05 2019Let $q$ be a prime power, $\mathbb F_q$ be the finite field of order $q$ and $\mathbb F_q(x)$ be the field of rational functions over $\mathbb F_q$. In this paper we classify all rational functions $\varphi\in \mathbb F_q(x)$ of degree 3 that induce a ... More
A note on forecasting demand using the multivariate exponential smoothing frameworkNov 15 2014Simple exponential smoothing is widely used in forecasting economic time series. This is because it is quick to compute and it generally delivers accurate forecasts. On the other hand, its multivariate version has received little attention due to the ... More
A closed-form estimator for the multivariate GARCH(1,1) modelMar 15 2013We provide a closed-form estimator based on the VARMA representation for the unrestricted multivariate GARCH(1,1). We show that all parameters can be derived using basic linear algebra tools. We show that the estimator is consistent and asymptotically ... More
Analysis of the Gibbs Sampler for Gaussian hierarchical models via multigrid decompositionMar 17 2017We study the convergence properties of the Gibbs Sampler in the context of posterior distributions arising from Bayesian analysis of Gaussian hierarchical models. We consider centred and non-centred parameterizations as well as their hybrids including ... More
Dilution effects in Ho$_{2-x}$Y$_x$Sn$_2$O$_7$: from the Spin Ice to the single-ion magnetOct 03 2008A study of the modifications of the magnetic properties of Ho$_{2-x}$Y$_x$Sn$_2$O$_7$ upon varying the concentration of diamagnetic Y$^{3+}$ ions is presented. Magnetization and specific heat measurements show that the Spin Ice ground-state is only weakly ... More
Evidence for impurity-induced frustration in La2CuO4Mar 18 2011Zero-field muon spin rotation and magnetization measurements were performed in La2Cu{1-x}MxO4, for 0<x< 0.12, where Cu2+ is replaced either by M=Zn2+ or by M=Mg2+ spinless impurity. It is shown that while the doping dependence of the sublattice magnetization ... More
Binary interaction algorithms for the simulation of flocking and swarming dynamicsMar 04 2012Microscopic models of flocking and swarming takes in account large numbers of interacting individ- uals. Numerical resolution of large flocks implies huge computational costs. Typically for $N$ interacting individuals we have a cost of $O(N^2)$. We tackle ... More
A canonical form for Gaussian periodic processesFeb 28 2012This article provides a representation theorem for a set of Gaussian processes; this theorem allows to build Gaussian processes with arbitrary regularity and to write them as limit of random trigonometric series. We show via Karhunen-Love theorem that ... More
Light 't Hooft Top PartnersNov 16 2015May 05 2016Vector-like quarks, usually dubbed top partners, are a common presence in composite Higgs models. Being composite objects, their mass is expected to be of the order of their inverse size, that is the condensation scale of the new strong interactions. ... More
Eisenstein Polynomials over Function FieldsJun 17 2015In this paper we compute the density of monic and non-monic Eisenstein polynomials of fixed degree having entries in an integrally closed subring of a function field over a finite field.
A Novel Nanoporous Graphite Based on Graphynes: First Principles Structure and Carbon Dioxide Preferential PhysisorptionOct 05 2016Ubiquitous graphene is a stricly 2D material representing an ideal adsorbing platform due to its large specific surface area as well as its mechanical strength and resistance to both thermal and chemical stresses. However, graphene as a bulk material ... More
Coherence-based multivariate analysis of high frequency stock market valuesMay 18 2008The paper tackles the problem of deriving a topological structure among stock prices from high frequency historical values. Similar studies using low frequency data have already provided valuable insights. However, in those cases data need to be collected ... More
Inverse Ising problem for one-dimensional chains with arbitrary finite-range couplingsSep 26 2011Nov 15 2011We study Ising chains with arbitrary multispin finite-range couplings, providing an explicit solution of the associated inverse Ising problem, i.e. the problem of inferring the values of the coupling constants from the correlation functions. As an application, ... More
Robustness of large-scale stochastic matrices to localized perturbationsAug 31 2013May 16 2015Upper bounds are derived on the total variation distance between the invariant distributions of two stochastic matrices differing on a subset W of rows. Such bounds depend on three parameters: the mixing time and the minimal expected hitting time on W ... More
Interacting Generalized Pólya Urn SystemsJan 07 2016We consider a system of interacting Generalized P\'olya Urns (GPUs) having irreducible mean replacement matrices. The interaction is modeled through the probability to sample the colors from each urn, that is defined as convex combination of the urn proportions ... More
Towards an ultra efficient kinetic scheme Part II: The high order caseDec 02 2012In a recent paper we presented a new ultra efficient numerical method for solving kinetic equations of the Boltzmann type (G. Dimarco, R. Loubere, Towards an ultra efficient kinetic scheme. Part I: basics on the 689 BGK equation, J. Comp. Phys., (2013), ... More
Causality re-establishedApr 28 2018Causality never gained the status of a "law" or "principle" in physics. Some recent literature even popularized the false idea that causality is a notion that should be banned from theory. Such misconception relies on an alleged universality of reversibility ... More
Diameter bounded equal measure partitions of Ahlfors regular metric measure spacesOct 18 2015Sep 27 2016The algorithm devised by Feige and Schechtman for partitioning higher dimensional spheres into regions of equal measure and small diameter is combined with David and Christ's construction of dyadic cubes to yield a partition algorithm suitable to any ... More
Gradient of the Objective Function for an Anisotropic Centroidal Voronoi Tessellation (CVT) - A revised, detailed derivationAug 24 2014In their recent article (2010), Levy and Liu introduced a generalization of Centroidal Voronoi Tessellation (CVT) - namely the Lp-CVT - that allows the computation of an anisotropic CVT over a sound mathematical framework. In this article a new objective ... More
Assessing Financial Model RiskJul 02 2013Jul 10 2013Model risk has a huge impact on any risk measurement procedure and its quantification is therefore a crucial step. In this paper, we introduce three quantitative measures of model risk when choosing a particular reference model within a given class: the ... More
Solvability and asymptotic analysis of a generalization of the Caginalp phase field systemJul 20 2011Aug 26 2011We study a diffusion model of phase field type, which consists of a system of two partial differential equations involving as variables the thermal displacement, that is basically the time integration of temperature, and the order parameter. Our analysis ... More
Approximation of target problems in Blackwell spacesJan 13 2009On a weakly Blackwell space we show how to define a Markov chain approximating problem, for the target problem. The approximating problem is proved to converge to the optimal reduced problem under different pseudometrics. A computational example of compression ... More
Constraining Milky Way mass with Hypervelocity StarsAug 04 2016We show that hypervelocity stars (HVSs) ejected from the center of the Milky Way galaxy can be used to constrain the mass of its halo. The asymmetry in the radial velocity distribution of halo stars due to escaping HVSs depends on the halo potential (escape ... More
The Dirac Quantum Automaton: a previewNov 11 2012Quantum Information and the new informational paradigm are entering the domain of quantum field theory and gravity, suggesting the quantum automata framework. The quantum automaton is the minimal-assumption extension to the Planck and ultrarelativistic ... More
Multiplicative noise, fast convolution, and pricingJul 07 2011In this work we detail the application of a fast convolution algorithm computing high dimensional integrals to the context of multiplicative noise stochastic processes. The algorithm provides a numerical solution to the problem of characterizing conditional ... More
Dynamic instability in a phenomenological model of correlated assetsAug 22 2005Apr 21 2006We show that financial correlations exhibit a non-trivial dynamic behavior. We introduce a simple phenomenological model of a multi-asset financial market, which takes into account the impact of portfolio investment on price dynamics. This captures the ... More
Scaling limits for continuous opinion dynamics systemsMar 17 2010Sep 22 2011Scaling limits are analyzed for stochastic continuous opinion dynamics systems, also known as gossip models. In such models, agents update their vector-valued opinion to a convex combination (possibly agent- and opinion-dependent) of their current value ... More
Transits Probabilities Around Hypervelocity and Runaway StarsSep 13 2016In the blooming field of exoplanetary science, NASA's Kepler Space Telescope has revolutionized our understanding of exoplanets. Kepler's very precise and long-duration photometry is ideal for detecting planetary transits around Sun-like stars. The forthcoming ... More
Asymmetric correlation matrices: an analysis of financial dataJan 31 2012Apr 27 2012We analyze the spectral properties of correlation matrices between distinct statistical systems. Such matrices are intrinsically non symmetric, and lend themselves to extend the spectral analyses usually performed on standard Pearson correlation matrices ... More
What do leaders know?Jun 17 2013Jul 23 2013The ability of a society to make the right decisions on relevant matters relies on its capability to properly aggregate the noisy information spread across the individuals it is made of. In this paper we study the information aggregation performance of ... More
Selective model-predictive control for flocking systemsMar 16 2016Oct 05 2016In this paper the optimal control of alignment models composed by a large number of agents is investigated in presence of a selective action of a controller, acting in order to enhance consensus. Two types of selective controls have been presented: an ... More
Exponential Runge-Kutta methods for stiff kinetic equationsOct 07 2010We introduce a class of exponential Runge-Kutta integration methods for kinetic equations. The methods are based on a decomposition of the collision operator into an equilibrium and a non equilibrium part and are exact for relaxation operators of BGK ... More
Fundamental Composite 2HDM: SU(N) with 4 flavoursAug 27 2015We present a new model of composite Higgs based on a gauged SU(N) group with 4 Dirac fermions in the fundamental representation. At low energy, the model has a global symmetry SU(4)$\times$SU(4) broken to the diagonal SU(4), containing 2 Higgs doublets ... More
Point Source Detection and Flux Determination with PGWaveOct 05 2016One of the largest uncertainties in the Point Source (PS) studies, at Fermi-LAT energies, is the uncertainty in the diffuse background. In general there are two approaches for PS analysis: background-dependent methods, that include modeling of the diffuse ... More
Microstructural Comparison of the Kinematics of Discrete and Continuum Dislocations ModelsJun 30 2015Mar 02 2016The Continuum Dislocation Dynamics (CDD) theory and the Discrete Dislocation Dynamics (DDD) method are compared based on concise mathematical formulations of the coarse graining of discrete data. A numerical tool for converting from a discrete to a continuum ... More
Searching for dark matter in final states with two jets and missing transverse energyDec 19 2018We reemphasise the usefulness of angular correlations in LHC searches for missing transverse energy ($E_T^{\mathrm{miss}}$) signatures that involve jet $(j)$ pairs with large invariant mass. For the case of mono-jet production via gluon-fusion, we develop ... More
Repeat-Until-Success circuits with fixed-point oblivious amplitude amplificationAug 08 2018Certain quantum operations can be built more efficiently through a procedure known as Repeat-Until-Success. Differently from other non-deterministic quantum operations, this procedure provides a classical flag which certifies the success or failure of ... More
A clustering algorithm for multivariate data streams with correlated componentsJul 05 2017Dec 21 2017Common clustering algorithms require multiple scans of all the data to achieve convergence, and this is prohibitive when large databases, with data arriving in streams, must be processed. Some algorithms to extend the popular K-means method to the analysis ... More