Results for "Davide Gandolfi"

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CoRoT 105906206: a short-period and totally eclipsing binary with a Delta Scuti type pulsatorMar 12 2014Eclipsing binary systems with pulsating components allow the determination of several physical parameters of the stars, such as mass and radius, that, when combined with the pulsation properties, can be used to constrain the modeling of stellar interiors ... More
CoRoT 223992193: Investigating the variability in a low-mass, pre-main sequence eclipsing binary with evidence of a circumbinary diskNov 16 2016CoRoT 223992193 is the only known low-mass, pre-main sequence eclipsing binary that shows evidence of a circumbinary disk. The system displays complex photometric and spectroscopic variability over a range of timescales and wavelengths. Using two optical ... More
CCD and photon-counting photometric observations of asteroids carried out at Padova and Catania observatoriesOct 09 2008We present the results of observational campaigns of asteroids performed at Asiago Station of Padova Astronomical Observatory and at M.G. Fracastoro Station of Catania Astrophysical Observatory, as part of the large research programme on Solar System ... More
A transiting M-dwarf showing beaming effect in the field of Ruprecht 147Aug 20 2018We report the discovery and characterization of an eclipsing M5V dwarf star, orbiting a slightly evolved F7V main sequence star. In contrast to previous claims in the literature, we confirm that the system does not belong to the galactic open cluster ... More
Self-Correction of Transmission on Regular TreesMar 26 2007We consider noisy binary channels on regular trees and introduce periodic enhancements consisting of locally self-correcting the signal in blocks without break of the symmetry of the model. We focus on the realistic class of within-descent self-correction ... More
KIC 1571511B: A Benchmark Low-Mass Star In An Eclipsing Binary System In The Kepler FieldNov 10 2011KIC 1571511 is a 14d eclipsing binary (EB) in the Kepler dataset. The secondary of this EB is a very low mass star with a mass of 0.14136 +/- 0.00036 M_sun and a radius of 0.17831 +0.00051/-0.00062 R_sun (statistical errors only). The overall system parameters ... More
Role of edge inclination in optical microdisk resonator for label-free sensingAug 18 2014In this paper we report on the measurement and modelling of enhanced optical refractometric sensors based on whispering-gallery-modes. The devices under test are optical microresonators made of silicon nitride on silicon oxide. In our approach, these ... More
K2-60b and epic 216468514b. A sub-jovian and a jovian planet from the k2 missionNov 11 2016We report the characterization and independant detection of K2-60b, as well as the detection and characterization of EPIC 216468514b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and ... More
Conformal Correlation Functions in the Brownian Loop SoupJan 23 2015Aug 28 2015We define and study a set of operators that compute statistical properties of the Brownian Loop Soup, a conformally invariant gas of random Brownian loops (Brownian paths constrained to begin and end at the same point) in two dimensions. We prove that ... More
Zeros of the Hurwitz zeta function in the interval (0,1)Mar 10 2010Feb 03 2011We first give a condition on the parameters $s,w$ under which the Hurwitz zeta function $\zeta(s,w)$ has no zeros and is actually negative. As a corollary we derive that it is nonzero for $w\geq 1$ and $s\in(0,1)$ and, as a particular instance, the known ... More
Reducing democratic type II supergravity on SU(3) x SU(3) structuresApr 03 2008Jun 10 2008Type II supergravity on backgrounds admitting SU(3) x SU(3) structure and general fluxes is considered. Using the generalized geometry formalism, we study dimensional reductions leading to N=2 gauged supergravity in four dimensions, possibly with tensor ... More
Higgs Physics at the Large Hadron ColliderMay 15 2001May 16 2001A major goal of the future Large Hadron Collider will be the Higgs boson search. In this paper the discovery In this paper the discovery potential is described as a function of the Higgs mass showing that a Standard Model Higgs boson can be discovered ... More
GRB Progenitors and EnvironmentMay 03 2005The study and knowledge of the environment of Gamma-Ray Bursts is of great interest from many points of view. For high redshift (z>0.5) events, the structure of the ambient medium is one of the best indicators of the nature and properties of the progenitor. ... More
Linear polarization on Gamma-Ray Bursts: from the prompt to the late afterglowDec 12 2003The past year has witnessed a large increase in our knowledge of the polarization properties of Gamma-Ray Burst (GRB) radiation. In the prompt phase, the measurement (albeit highly debated) of a large degree of linear polarization in GRB 021206 has stimulated ... More
X-ray lines, progenitor and beaming of Gamma-Ray BurstsNov 08 2002X-ray emission features have been detected in at least five GRB afterglows. Their detection and properties are of great importance in our understanding of the nature of the GRB progenitor. Moreover, they provide us with an un-collimated source of photons, ... More
Gamma-Ray Bursts environment and progenitorsJan 16 2003The properties of the ambient medium in which GRBs go off are an important piece of the puzzle, not only as an issue in itself, but because of their link with the nature of the progenitor. In this review, I describe and critically comment the various ... More
S3 as a flavour symmetry for quarks and leptons after the Daya Bay result on θ13Mar 14 2012We present a model based on the flavour group S3 X Z3 X Z6 to explain the main features of fermion masses and mixing. In particular, in the neutrino sector the breaking of the S3 symmetry is responsible for a naturally small r=\Delta m^2_sol/\Delta m^2_atm ... More
Impact of nuclear effects in the measurement of neutrino oscillation parametersOct 05 2011In recent years the experimental study of neutrino oscillations has much contributed to our knowledge of particle physics by establishing non vanishing neutrino masses and by measuring or constraining the corresponding mixing angles. Within the domain ... More
A See-Saw $S_4$ model for fermion masses and mixingsNov 18 2009Apr 13 2010We present a supersymmetric see-saw $S_4$ model giving rise to the most general neutrino mass matrix compatible with Tri-Bimaximal mixing. We adopt the $S_4\times Z_5$ flavour symmetry, broken by suitable vacuum expectation values of a small number of ... More
Aspects of Symmetry in Sine-Gordon TheoryNov 30 2001As a prototype of powerful non-abelian symmetry in an Integrable System, I will show the appearance of a Witt algebra of vector fields in the SG theory. This symmetry does not share anything with the well-known Virasoro algebra of the conformal $c=1$ ... More
Geometrical Loci and CFTs via the Virasoro Symmetry of the mKdV-SG hierarchy: an excursusAug 10 2004We will describe the appearance of specific algebraic KdV potentials as a consequence of a requirement on a integro-differential expression. This expression belongs to a class generated by means of Virasoro vector fields acting on the KdV field. The ``almost'' ... More
To found or not to found: that is the questionSep 02 2014Sep 10 2014Aim of this paper is to confute two views, the first about Schr\"oder's presumptive foundationalism, according to he founded mathematics on the calculus of relatives; the second one mantaining that Schr\"oder only in his last years (from 1890 onwards) ... More
On the Concept of Possibility in Quantum MechanicsJun 06 2010Oct 25 2012This paper has been withdrawn by the author. In this short paper I introduce a concept of possibility in order to vindicate Everett's Theory of many worlds. The main idea is that there is only one world: the real. After the wave-collapse, we have again ... More
Observable measure of quantum coherence in finite dimensional systemsMar 11 2014Oct 22 2014Quantum coherence is the key resource for quantum technology, with applications in quantum optics, information processing, metrology and cryptography. Yet, there is no universally efficient method for quantifying coherence either in theoretical or in ... More
Solving PVI by Isomonodromy DeformationsJun 14 2011Jul 27 2011The critical and asymptotic behaviors of solutions of the sixth Painlev\'e equation, an their parametrization in terms of monodromy data, are synthetically reviewed. The explicit formulas are given. This paper has been withdrawn by the author himself, ... More
Galois representations attached to abelian varieties of CM typeJun 15 2015Aug 12 2015Let $K$ be a number field, $A/K$ be an absolutely simple abelian variety of CM type, and $\ell$ be a prime number. We give explicit bounds on the degree over $K$ of the division fields $K(A[\ell^n])$, and when $A$ is an elliptic curve we also describe ... More
Explicit surjectivity of Galois representations attached to abelian surfaces and $\operatorname{GL}_2$-varietiesNov 06 2014Dec 31 2015Let $A$ be an absolutely simple abelian variety without (potential) complex multiplication, defined over the number field $K$. Suppose that either $\dim A=2$ or $A$ is of $\operatorname{GL}_2$-type: we give an explicit bound $\ell_0(A,K)$ such that, for ... More
Monte Carlo Calculation for the neutron-rich Ca isotopesMay 24 2006Feb 13 2008We computed ground-state energies of calcium isotopes from 42Ca to 48Ca by means of the Auxiliary Field Diffusion Monte Carlo (AFDMC) method. Calculations were performed by replacing the 40Ca core with a mean-field self consistent potential computed using ... More
Mathematical vs Empirical MeasurementJun 03 2010Oct 25 2012This paper has been withdrawn by the author. In this short paper I will put in evidence a problem nested in Ozawa's effort to block von Neumann's chains and in his attributing the wave-collapse to a interaction between systems. This suggests distinguishing ... More
Automatically Creating Bilingual Lexicons for Machine Translation from Bilingual TextJul 20 1998A method is presented for automatically augmenting the bilingual lexicon of an existing Machine Translation system, by extracting bilingual entries from aligned bilingual text. The proposed method only relies on the resources already available in the ... More
A geometric approach to quantum control in projective Hilbert spacesAug 28 2015May 03 2016A quantum theory in a finite-dimensional Hilbert space can be geometrically formulated as a proper Hamiltonian theory as explained in [2, 3, 7, 8]. From this point of view a quantum system can be described in a classical-like framework where quantum dynamics ... More
A geometric Hamiltonian description of composite quantum systems and quantum entanglementAug 08 2014Finite-dimensional Quantum Mechanics can be geometrically formulated as a proper classical-like Hamiltonian theory in a projective Hilbert space. The description of composite quantum systems within the geometric Hamiltonian framework is discussed in this ... More
On the Tree-Like Structure of Rings in Dense SolutionsSep 24 2016Oct 22 2016One of the most challenging problems in polymer physics is providing a theoretical description for the behaviour of rings in dense solutions and melts. Although it is nowadays well established that the overall size of a ring in these conditions scales ... More
S-duality of boundary conditions and the Geometric Langlands programSep 28 2016Nov 08 2016Maximally supersymmetric gauge theory in four dimensions admits local boundary conditions which preserve half of the bulk supersymmetries. The S-duality of the bulk gauge theory can be extended in a natural fashion to act on such half-BPS boundary conditions. ... More
The Direct Monodromy Problem of Painleve-IJul 09 2010Oct 08 2010The Painleve first equation can be represented as the equation of isomonodromic deformation of a Schrodinger equation with a cubic potential. We introduce a new algorithm for computing the direct monodromy problem for this Schrodinger equation. The algorithm ... More
Trap effects and continuum limit of the Hubbard model in the presence of an harmonic potentialNov 02 2016We investigate the ground-state (GS) density properties of a system of spin-$1/2$ particles described by the $d$-dimensional Hubbard model in the presence of an harmonic trap. In particular we consider this system at zero temperature in the so called ... More
Interpreting Quantum Discord in Quantum MetrologyFeb 16 2015Nov 03 2015Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of quantum discord ... More
VIMOS IFU as a tool to observe the cores of high z clustersSep 28 2001Research on the core of medium and high z clusters of galaxies can derive great benefits from integral field spectroscopy, and a key role in this respect will be played by the Integral Field Unit (IFU) being developed by the VIRMOS Consortium as part ... More
A dispersive estimate for the linear wave equation with an electromagnetic potentialJan 02 2006We consider radial solutions to the Cauchy problem for the linear wave equation with a small short-range electromagnetic potential (the "square version" of the massless Dirac equation with a potential) and zero initial data. We prove two a priori estimates ... More
On the analytic bijections of the rationals in $[0,1]$Jun 22 2016We carry out an arithmetical study of analytic functions $f: [0,1] \to [0,1]$ that by restriction induce a bijection $\mathbb{Q} \cap [0,1] \to \mathbb{Q} \cap [0,1]$. The existence of such functions shows that, unless $f(x)$ has some additional property ... More
Pink-type results for general subgroup of $\operatorname{SL}_2(\mathbb{Z}_\ell)^n$Jan 16 2015Aug 09 2015We study open subgroups $G$ of $\operatorname{SL}_2(\mathbb{Z}_\ell)^n$ in terms of some associated Lie algebras without assuming that $G$ is a pro-$\ell$ group, thereby extending a theorem of Pink. The result has applications to the study of families ... More
A Semi-Linear Backward Parabolic cauchy Problem with Unbounded Coefficients of Hamilton-Jacobi-Bellman Type and Applications to optimal controlFeb 03 2014We obtain weighted uniform estimates for the gradient of the solutions to a class of linear parabolic Cauchy problems with unbounded coefficients. Such estimates are then used to prove existence and uniqueness of the mild solution to a semi-linear backward ... More
Feedback based Reputation on top of the Bitcoin BlockchainFeb 05 2015Feb 10 2015The ability to assess the reputation of a member in a web community is a need addressed in many different ways according to the many different stages in which the nature of communities has evolved over time. In the case of reputation of goods/services ... More
Geometry and dimensionality reduction of feature spaces in primary visual cortexSep 14 2015Some geometric properties of the wavelet analysis performed by visual neurons are discussed and compared with experimental data. In particular, several relationships between the cortical morphologies and the parametric dependencies of extracted features ... More
Sufficient and equivalent criteria for the Riemann HypothesisMar 10 2010Aug 30 2011The paper presents several new sufficient conditions, as well as new equivalent criteria for the classical Riemann Hypothesis. Noteworthy are also other statements and remarks about $\zeta$ to be found throughout the paper.
Monte Carlo radiation transfer simulations of photospheric emission in long-duration Gamma-Ray BurstsMay 11 2016Jul 19 2016We present MCRaT, a Monte Carlo Radiation Transfer code for self-consistently computing the light curves and spectra of the photospheric emission from relativistic, unmagnetized jets. We apply MCRaT to a relativistic hydrodynamic simulation of a long ... More
Polarization in the prompt emission of gamma-ray bursts and their afterglowsJul 31 2006Synchrotron is considered the dominant emission mechanism in the production of gamma-ray burst photons in the prompt as well as in the afterglow phase. Polarization is a characteristic feature of synchrotron and its study can reveal a wealth of information ... More
Precursor activity in bright long BATSE gamma-Ray BurstsNov 29 2004Dec 21 2004We study a sample of bright long BATSE GRB light curves in the 200 s before the detection of the GRB prompt emission. We find that in a sizable fraction of cases (20 %) there is evidence of emission above the background coming from the same direction ... More
Recursive Betti numbers for Cohen-Macaulay $d$-partite clutters arising from posetsNov 20 2014Oct 18 2015A natural extension of bipartite graphs are $d$-partite clutters, where $d \geq 2$ is an integer. For a poset $P$, Ene, Herzog and Mohammadi introduced the $d$-partite clutter $\mathcal{C}_{P,d}$ of multichains of length $d$ in $P$, showing that it is ... More
Hidden Virasoro Symmetry of the Sine Gordon TheoryDec 01 2000May 22 2001In the framework of the Sine-Gordon (SG) theory we will present the construction of a dynamical Virasoro symmetry which has nothing to do with the space-time Virasoro symmetry of 2D CFT. Although, it is non-local in the SG field theory, nevertheless it ... More
Tabulation of PVI Transcendents and Parametrization Formulas (August 17, 2011)Aug 17 2011Oct 01 2012The critical and asymptotic behaviors of solutions of the sixth Painlev\'e equation PVI, obtained in the framework of the monodromy preserving deformation method, and their explicit parametrization in terms of monodromy data, are tabulated.
On the Critical Behavior, the Connection problem and the Elliptic representation of a Painleve VI equation (Spring 2001)Oct 07 2010We find a class of solutions of the sixth Painleve' equation appearing in the theory of WDVV equations. This class covers almost all the monodromy data associated to the equation, except one point in the space of the data. We find the critical behavior ... More
Fractionally-addressed delay linesMay 17 2000Jun 12 2000While traditional implementations of variable-length digital delay lines are based on a circular buffer accessed by two pointers, we propose an implementation where a single fractional pointer is used both for read and write operations. On modern general-purpose ... More
A MILP model for single machine family scheduling with sequence-dependent batch setup and controllable processing timesJan 29 2015Mar 02 2015A mathematical programming model for a class of single machine family scheduling problem is described in this technical report, with the aim of comparing the performance in solving the scheduling problem by means of mathematical programming with the performance ... More
Target annihilation by diffusing particles in inhomogeneous geometriesSep 03 2009The survival probability of immobile targets, annihilated by a population of random walkers on inhomogeneous discrete structures, such as disordered solids, glasses, fractals, polymer networks and gels, is analytically investigated. It is shown that, ... More
Local Picard Group of Binoids and Their AlgebrasNov 06 2016Nov 08 2016We begin by introducing schemes of binoids, invertible $\mathcal{O}_M$-sets and cohomology of sheaves of abelian groups defined on schemes of binoids. We define the so-called punctured combinatorial \v{C}ech-Picard complex, whose first cohomology computes ... More
Painleve I, Coverings of the Sphere and Belyi FunctionsJul 18 2012Oct 22 2012The theory of poles of solutions of Painleve-I is equivalent to the Nevanlinna problem of constructing a meromorphic function ramified over five points - counting multiplicities - and without critical points. We construct such meromorphic functions as ... More
Analyticity of non-symmetric Ornstein-Uhlenbeck semigroup with respect to a weighted Gaussian measureFeb 06 2019In this paper we show that the realization in $L^p(X,\nu_\infty)$ of the nonsymmetric Ornstein-Uhlenbeck operator $L$ is sectorial for any $p\in(1,+\infty)$ and we provide an explicit sector of analyticity. Here $(X,\mu_\infty,H_\infty)$ is an abstract ... More
Three dimensional Conformal Field Theories from Sasakian seven-manifoldsFeb 29 2000We present the construction of the candidate conformal field theories dual to $AdS_4$ non-maximally supersymmetric compactifications of 11D supergravity. We compare the spectra of the two theories and discuss the realization of the baryonic symmetries. ... More
Matching Procedure for the Sixth Painlevé Equation (May 2006)Oct 07 2010We present a constructive procedure to obtain the critical behavior of Painleve' VI transcendents and solve the connection problem. This procedure yields two and one parameter families of solutions, including trigonometric and logarithmic behaviors, and ... More
Nonautonomous Ornstein-Uhlenbeck operators in weighted spaces of continuous functionsJul 19 2016We consider the nonautonomous Ornstein-Uhlenbeck operator in some weighted spaces of continuous functions in $\R^N$. We prove sharp uniform estimates for the spatial derivatives of the associated evolution operator $\OU$, which we use to prove optimal ... More
On the uniform Rasmussen-Tamagawa conjecture in the CM caseNov 29 2015We prove a uniform version of a finiteness conjecture due to Rasmussen and Tamagawa in the case of CM abelian varieties. This extends recent results concerning CM elliptic curves to CM abelian varieties of arbitrary dimension.
Mixing for suspension flows over skew-translations and time-changes of quasi-abelian filiform nilflowsJun 28 2017Feb 12 2018We consider suspension flows over uniquely ergodic skew-translations on a $d$-dimensional torus $\mathbb{T}^d$, for $d \geq 2$. We prove that there exists a set $\mathscr{R}$ of smooth functions, which is dense in the space $\mathscr{C}(\mathbb{T}^d)$ ... More
Mixed quasi-étale surfaces, new surfaces of general type with $p_g=0$ and their fundamental groupMay 06 2011Apr 23 2013We call a projective surface $X$ mixed quasi-\'etale quotient if there exists a curve $C$ of genus $g(C)\geq 2$ and a finite group $G$ that acts on $C\times C$ exchanging the factors such that $X=(C\times C)/G$ and the map $C\times C \rightarrow X$ has ... More
The projected Newton-Kleinman method for the algebraic Riccati equationJan 29 2019The numerical solution of the algebraic Riccati equation is a challenging task especially for very large problem dimensions. In this paper we present a new algorithm that combines the very appealing computational features of projection methods with the ... More
Effective-Range Dependence of Resonantly Interacting FermionsMay 22 2012Nov 15 2012We extract the leading effective range corrections to the equation of state of the unitary Fermi gas from ab initio fixed-node quantum Monte Carlo (FNQMC) calculations in a periodic box using a density functional theory (DFT), and show them to be universal ... More
Resonantly Interacting Fermions In a BoxNov 09 2010Jun 16 2011We use two fundamental theoretical frameworks to study the finite-size (shell) properties of the unitary gas in a periodic box: 1) an ab initio Quantum Monte Carlo (QMC) calculation for boxes containing 4 to 130 particles provides a precise and complete ... More
BK-type inequalities and generalized random-cluster representationsMar 16 2012Recently, van den Berg and Jonasson gave the first substantial extension of the BK inequality for non-product measures: they proved that, for k-out-of-n measures, the probability that two increasing events occur disjointly is at most the product of the ... More
On the role of Allee effect and mass migration in survival and extinction of a speciesMar 20 2010May 14 2012We use interacting particle systems to investigate survival and extinction of a species with colonies located on each site of $\mathbb {Z}^d$. In each of the four models studied, an individual in a local population can reproduce, die or migrate to neighboring ... More
The Problem of the Observer in PhysicsJun 01 2010Oct 25 2012This paper has been withdrawn by the author. In this short paper I present a new approach to the problem of measurement, based on the difference between language (reality) and meta-language (meta-reality). This way, it will be shown as the measurement ... More
Bohmian Classical Limit in Bounded RegionsMar 09 2016Bohmian mechanics is a realistic interpretation of quantum theory. It shares the same ontology of classical mechanics: particles following continuous trajectories in space through time. For this ontological continuity, it seems to be a good candidate ... More
Open-loop quantum control as a resource for secure communicationsDec 17 2015Feb 01 2016Properties of unitary time evolution of quantum systems can be applied to define quantum cryptographic protocols. Dynamics of a qubit can be exploited as a data encryption/decryption procedure by means of timed measurements, implementation of an open-loop ... More
New methods for the computation of the linear response within the density functional theory in spin polarized system (Metodi innovativi per il calcolo della risposta lineare in density functional theory per sistemi spin polarizzati)Aug 15 2012In the present thesis we study absorption spectra of spin polarized isolated systems. Thus we introduce the density functional theory (DFT) formalism and its time dependent extension (TDDFT) together with the approximation used. In particula the Casida ... More
Analyticity and criticality results for the eigenvalues of the biharmonic operatorMar 09 2016We consider the eigenvalues of the biharmonic operator subject to several homogeneous boundary conditions (Dirichlet, Neumann, Navier, Steklov). We show that simple eigenvalues and elementary symmetric functions of multiple eigenvalues are real analytic, ... More
On the Tree-Like Structure of Rings in Dense SolutionsSep 24 2016One of the most challenging problems in polymer physics is providing a theoretical description for the behaviour of rings in dense solutions and melts. Although it is nowadays well established that the overall size of a ring in these conditions scales ... More
HyLTL: a temporal logic for model checking hybrid systemsAug 24 2013The model-checking problem for hybrid systems is a well known challenge in the scientific community. Most of the existing approaches and tools are limited to safety properties only, or operates by transforming the hybrid system to be verified into a discrete ... More
Operators and vacua of N=1 field theoriesDec 17 2009We review the idea of Hilbert Series as a tool to study the moduli space and the BPS operators of four dimensional N=1 supersymmetric field theories. We concentrate on the particular case of N=1 superconformal field theories living on N D3 branes at toric ... More
Master Space and Hilbert Series for N=1 Field TheoriesFeb 12 2009Master Space and Hilbert Series are general tools to study any N=1 supersymmetric field theory. We concentrate on the particular case of N=1 super conformal field theories living on D3 branes at toric Calabi Yau singularities. We start reviewing the topic ... More
Checking Flavour Models at Neutrino FacilitiesAug 21 2013Nov 29 2013In the recent years, the industry of model building has been the subject of the intense activity, especially after the measurement of a relatively large values of the reactor angle. Special attention has been devoted to the use of non-abelian discrete ... More
Sterile neutrinos at future long baseline experimentsDec 18 2008In this talk we review the current status of sterile neutrino searches and discuss the potential of future long baseline experiments to study their properties.
GRB progenitors and their environmentsNov 07 2006The detection of supernova features in the late spectra of several gamma-ray burst afterglows has shown that at least a fraction of long-duration gamma-ray bursts are associated to the final evolutionary stages of massive stars. Such direct observations ... More
Gamma-Ray Burst Progenitors Confront ObservationsFeb 02 2004The discovery of a supernova emerging at late times in the afterglow of GRB 030329 has apparently settled the issue on the nature of the progenitor of gamma-ray bursts. We now know that at least a fraction of cosmological GRBs are associated with the ... More
Thermal components in the early X-ray afterglow of GRBsOct 14 2002Dec 12 2002The possible presence of thermal components in the early X-ray afterglows of gamma-ray bursts is investigated. We discuss both the presence of a thermal continuum and, in particular, of collisional X-ray emission lines. We compute the predicted luminosity ... More
The role of photon scattering in shaping the lightcurves and spectra of gamma-ray burstsJun 18 2002Sep 01 2002We analyze the power spectra of the lightcurves of long gamma-ray bursts, dividing the sample in bins of luminosity, using the recently discovered variability-luminosity correlation. We find that the value of the variability parameter strongly correlates ... More
Classical solutions to quasilinear parabolic problems with dynamic boundary conditionsApr 23 2015We study linear nonautonomous parabolic systems with dynamic boundary conditions. Next, we apply these results to show a theorem of local existence and uniqueness of a classical solution to a second order quasilinear system with nonlinear dynamic boundary ... More
Parabolic problems with general Wentzell boundary conditions and diffusion on the boundaryApr 21 2015We show a result of maximal regularity in spaces of H\"older continuous function, concerning linear parabolic systems, with dynamic or Wentzell boundary conditions, with an elliptic diffusion term on the boundary.
An Asymptotic Reduction of a Painleve' VI equation to a Painleve' III (January 2011)Jan 25 2011When the independent variable is close to a critical point, it is shown that PVI can be asymptotically reduced to PIII. In this way, it is possible to compute the leading term of the critical behaviors of PVI transcendents starting from the behaviors ... More
A Review on The Sixth Painleve' EquationOct 01 2012Dec 05 2015For the Painlev\'e 6 transcendents, we provide a unitary description of the critical behaviours, the connection formulae, their complete tabulation, and the asymptotic distribution of the poles close to a critical point.
Poles Distribution of PVI Transcendents close to a Critical Point (summer 2011)Apr 27 2011Apr 14 2012The distribution of the poles of branches of the Painleve' VI transcendents associated to semi-simple Frobenius manifolds is determined close to a critical point. It is shown that the poles accumulate at the critical point, asymptotically along two rays. ... More
Advances in the optimization of silicon-based thermoelectrics: a theory perspectiveFeb 13 2019Thermoelectric devices convert temperature gradients into electrical power and vice versa, thus enabling energy scavenging from waste heat, sensing and cooling. Yet, many of these attractive applications are hindered by the limited efficiency of thermoelectric ... More
Roots of unity and torsion points of abelian varietiesJul 03 2015Dec 31 2015We answer a question raised by Hindry and Ratazzi concerning the intersection between cyclotomic extensions of a number field $K$ and extensions of $K$ generated by torsion points of an abelian variety over $K$. We prove that a weak version of the property ... More
Explicit open image theorems for abelian varieties with trivial endomorphism ringAug 06 2015Jan 04 2016Let $K$ be a number field and $A/K$ be an abelian variety of dimension $g$ with $\operatorname{End}_{\overline{K}}(A)=\mathbb{Z}$. We provide a semi-effective bound $\ell_0(A/K)$ such that the natural Galois representation attached to $T_\ell A$ is onto ... More
An explicit open image theorem for products of elliptic curvesJan 19 2015Nov 29 2015Let $K$ be a number field and $E_1, \ldots, E_n$ be elliptic curves over $K$, pairwise non-isogenous over $\overline{K}$ and without complex multiplication over $\overline{K}$. We study the image of the adelic representation of the absolute Galois group ... More
One-basedness and reductions of elliptic curves over real closed fieldsAug 03 2012Building on the positive solution of Pillay's conjecture we present a notion of "intrinsic" reduction for elliptic curves over a real closed field K. We compare such notion with the traditional algebro-geometric reduction and produce a classification ... More
A simple way to reduce factorization problems to SATJun 23 2017As Cook-Levin theorem showed, every NP problem can be reduced to SAT in polynomial time. In this paper I show a simpler and more efficent method to reduce some factorization problems to the satisfability of a boolean formula.
Trace heat kernel asymptotics in 3D contact sub-Riemannian geometryMay 06 2011Nov 04 2011In this paper we study the small time asymptotics for the heat kernel on a sub-Riemannian manifold, using a perturbative approach. We then explicitly compute, in the case of a 3D contact structure, the first two coefficients of the small time asymptotics ... More
S-duality of boundary conditions and the Geometric Langlands programSep 28 2016Maximally supersymmetric gauge theory in four dimensions admits local boundary conditions which preserve half of the bulk supersymmetries. The S-duality of the bulk gauge theory can be extended in a natural fashion to act on such half-BPS boundary conditions. ... More
Between Being and Becoming: a meta-theoretical approach to irreversibilitySep 05 2013The relationship between reversible-dynamical and irreversible-thermodynamic descriptions is analyzed from a meta-theoretical point of view. A network of inter-theoretical relations is drawn by means of asymptotic relations and complementarity. It is ... More
Generalized Riemann hypotheses: sufficient and equivalent criteriaMay 10 2010Oct 22 2010This paper presents new sufficient and equivalent conditions for the generalized version of the Riemann Hypothesis. The paper derives also statements and remarks concerning zero-free regions, modified Hadamard-product formulas and the behaviour of $|\frac{L(\bar{\chi},s)}{L(\chi,1-s)}|$. ... More
X-ray Polarization of Gamma-Ray BurstsJun 23 2009The degree and the temporal evolution of linear polarization in the prompt and afterglow emission of gamma-ray bursts is a very robust diagnostic of some key features of gamma-ray bursts jets and their micro and macro physics. In this contribution, I ... More