Results for "Nicoletta Daniele"

total 1918took 0.10s
Quantitative and qualitative cohomological properties for non-Kähler manifoldsJul 25 2015Mar 18 2016We introduce a "qualitative property" for Bott-Chern cohomology of complex non-K\"ahler manifolds, which is motivated in view of the study of the algebraic structure of Bott-Chern cohomology. We prove that such a property characterizes the validity of ... More
On the cohomology of almost complex and symplectic manifolds and proper surjective mapsJan 29 2016Let $(X,J)$ be an almost-complex manifold. In \cite{li-zhang} Li and Zhang introduce $H^{(p,q),(q,p)}_J(X)_{\rr}$ as the cohomology subgroups of the $(p+q)$-th de Rham cohomology group formed by classes represented by real pure-type forms. Given a proper, ... More
Propagation of Chaos for a Balls into Bins ModelSep 21 2018Dec 18 2018Consider a finite number of balls initially placed in $L$ bins. At each time step a ball is taken from each non-empty bin. Then all the balls are uniformly reassigned into bins. This finite Markov chain is called Repeated Balls-into-Bins process and is ... More
On geometric Bott-Chern formality and deformationsFeb 12 2015A notion of geometric formality in the context of Bott-Chern and Aeppli cohomologies on a complex manifold is discussed. In particular, by using Aeppli-Bott-Chern-Massey triple products, it is proved that geometric Aeppli-Bott-Chern formality is not stable ... More
Rotating black holes in the FI-gauged $N=2$, $D=4$ $\overline{\mathbb{C}\text{P}}^n$ modelFeb 08 2019We construct supersymmetric black holes with rotation or NUT charge for the $\overline{\mathbb{C}\text{P}}^n$- and the $\text{t}^3$ model of $N=2$, $D=4$ $\text{U}(1)$ FI-gauged supergravity. The solutions preserve 2 real supercharges, which are doubled ... More
Classification of linearly compact simple N=6 3-algebrasOct 18 2010Nov 07 2010$N\leq 8$ 3-algebras have recently appeared in N-supersymmetric 3-dimensional Chern-Simons gauge theories. In our previous paper we classified linearly compact simple N = 8 n-algebras for any $n \geq 3$. In the present paper we classify linearly compact ... More
Rheological investigation of gels formed by competing interactions: A numerical studyFeb 07 2019A transition from solid-like to liquid-like behavior occurs when colloidal gels are subjected to a prolonged exposure to a steady shear. This phenomenon, which is characterized by a yielding point, is found to be strongly dependent on the packing fraction. ... More
Discontinous change from thermally- to geometrically- dominated effective interactions in colloidal solutionsAug 23 2016We report numerical results on the effective potential arising between two colloids immersed in a self-assembling cosolute which forms reversible clusters. The potential is evaluated at cosolute state points with different densities and temperatures but ... More
The ergodic problem for some subelliptic operators with unbounded coefficientsOct 29 2015Jan 19 2016We study existence and uniqueness of the invariant measure for a stochastic process with degenerate diffusion, whose infinitesimal generator is a linear subelliptic operator in the whole space R N with coefficients that may be unbounded. Such a measure ... More
A global existence result for a Keller-Segel type system with supercritical initial dataJun 19 2015We consider a parabolic-elliptic Keller-Segel type system, which is related to a simplified model of chemotaxis. Concerning the maximal range of existence of solutions, there are essentially two kinds of results: either global existence in time for general ... More
On a singular Liouville-type equation and the Alexandrov isoperimetric inequalitySep 06 2016We obtain a generalized version of an inequality, first derived by C. Bandle in the analytic setting, for weak subsolutions of a singular Liouville-type equation. As an application we obtain a new proof of the Alexandrov isoperimetric inequality on singular ... More
Self gravitating cosmic strings and the Alexandrov's inequality for Liouville-type equationsSep 10 2014Motivated by the study of self gravitating cosmic strings, we pursue the well known method by C. Bandle to obtain a weak version of the classical Alexandrov's isoperimetric inequality. In fact we derive some quantitative estimates for weak subsolutions ... More
Non-coercive first order Mean Field GamesNov 30 2018We study first order evolutive Mean Field Games where the Hamiltonian is non-coercive. This situation occurs, for instance, when some directions are "forbidden" to the generic player at some points. We establish the existence of a weak solution of the ... More
Generalized Fluctuation-Dissipation Relation and Effective Temperature upon Heating a Deeply Supercooled LiquidOct 10 2012We show that a generalized fluctuation-dissipation relation applies upon instantaneously increasing the temperature of a deeply supercooled liquid. This has the same two-step shape of the relation found upon cooling the liquid, but with opposite violation, ... More
Mixing time of a kinetically constrained spin model on trees: power law scaling at criticalityNov 26 2012On the rooted $k$-ary tree we consider a 0-1 kinetically constrained spin model in which the occupancy variable at each node is re-sampled with rate one from the Bernoulli(p) measure iff all its children are empty. For this process the following picture ... More
Fredrickson-Andersen one spin facilitated model out of equilibriumMay 21 2012We consider the Fredrickson and Andersen one spin facilitated model (FA1f) on an infinite connected graph with polynomial growth. Each site with rate one refreshes its occupation variable to a filled or to an empty state with probability $p\in[0,1]$ or ... More
Facilitated spin models: recent and new resultsDec 12 2007Facilitated or kinetically constrained spin models (KCSM) are a class of interacting particle systems reversible w.r.t. to a simple product measure. Each dynamical variable (spin) is re-sampled from its equilibrium distribution only if the surrounding ... More
Facilitated oriented spin models:some non equilibrium resultsOct 23 2008We analyze the relaxation to equilibrium for kinetically constrained spin models (KCSM) when the initial distribution $\nu$ is different from the reversible one, $\mu$. This setting has been intensively studied in the physics literature to analyze the ... More
On the depth of quantum spaceJul 22 2011We focus on the question: "Is space fundamentally discrete or continuous?" in the context of current quantum gravity research. In particular, we paint a scenario based on the idea that 'quantum space' is a sort of peculiar condensed matter system, and ... More
A note on the multiplicative gamma processOct 11 2016Adaptive dimensionality reduction in high-dimensional problems is a key topic in statistics. The multiplicative gamma process prior takes a step in this direction, but improved studies on its properties are required to ease implementation. This note addresses ... More
X Ray Precursors in SGRs: Precessing Gamma Jet TailsMay 16 2001May 18 2001Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB, and also rare Soft Gamma Repeaters, SGR, events are in complete disagreement with any Fireball, or Magnetar, one-shoot explosive scenarios. Fireball model in last two years has ... More
GRBs and the Ghost of the FireballMar 17 2001Jan 17 2002Gamma Ray Burst has been widely believed in last decade to be super-explosions: the Fireball. We are argue on the contrary that GRBs (as well as Soft Gamma Repeaters SGR) are precessing Gamma Jets. We remind the list of contradiction that Fireball and ... More
Invisible Higgs in large extra dimension modelsAug 06 2004In large extra dimension models the presence of an interaction between the Ricci scalar curvature and the Higgs doublet of the Standard Model can give rise to an invisible decay of the Higgs to Kaluza Klein graviscalars. The corresponding invisible width ... More
Probing extra dimensions through the invisible Higgs decayMar 22 2005In the large extra dimension model of Arkani-Hamed, Dimopoulos and Dvali the presence of an interaction between the Ricci scalar curvature and the Higgs doublet of the Standard Model makes a light Higgs boson observable at LHC at the 5 sigma level through ... More
Universal Lagrangian BundlesApr 10 2013The obstruction to construct a Lagrangian bundle over a fixed integral affine manifold was constructed by Dazord and Delzant in \cite{daz_delz} and shown to be given by `twisted' cup products in \cite{sepe_lag}. This paper uses the topology of universal ... More
Almost Lagrangian ObstructionJun 22 2011The aim of this paper is to describe the obstruction for an almost Lagrangian fibration to be Lagrangian, a problem which is central to the classification of Lagrangian fibrations and, more generally, to understanding the obstructions to carry out surgery ... More
The cohomologies of the Iwasawa manifold and of its small deformationsDec 18 2012We prove that, for some classes of complex nilmanifolds, the Bott-Chern cohomology is completely determined by the Lie algebra associated to the nilmanifold with the induced complex structure. We use these tools to compute the Bott-Chern and Aeppli cohomologies ... More
Gravitational collapse of Hagedorn fluidsMay 11 2016We consider a toy model for relativistic collapse of an homogeneous perfect fluid that takes into account an equation of state for high density matter, in the form of an Hagedorn phase, and semiclassical corrections in the strong field. We show that collapse ... More
Rank 2 arithmetically Cohen-Macaulay bundles on a nonsingular cubic surfaceApr 24 2005Jul 27 2006Rank 2 indecomposable arithmetically Cohen-Macaulay bundles E on a nonsingular cubic surface X in P^3 are classified, by means of the possible forms taken by the minimal graded free resolution of E over P^3. The admissible values of the Chern classes ... More
Yet again on two examples by Iyama and YoshinoSep 11 2014We give an elementary proof of Iyama-Yoshino's classification of rigid MCM modules on Veronese embeddings in P9.
Logic on the n-cubeJul 24 2012We endow the partially ordered set of nonempty faces of the n-cube with a distinguished 0-dimensional face and three operations that naturally extend the Rota-Metropolis partial operations. While the structures thus obtained turn out to be term-equivalent ... More
TeV gamma-UHECR anisotropy by decaying nuclei in flight: first neutrino traces?Jul 01 2012Ultra High Cosmic Rays) made by He-like lightest nuclei might solve the AUGER extragalactic clustering along Cen A. Moreover He like UHECR nuclei cannot arrive from Virgo because the light nuclei fragility and opacity above a few Mpc, explaining the Virgo ... More
Group field theory as the 2nd quantization of Loop Quantum GravityOct 29 2013Aug 18 2015We construct a 2nd quantized reformulation of canonical Loop Quantum Gravity at both kinematical and dynamical level, in terms of a Fock space of spin networks, and show in full generality that it leads directly to the Group Field Theory formalism. In ... More
A note on the multiplicative gamma processOct 11 2016Oct 30 2016Adaptive dimensionality reduction in high-dimensional problems is a key topic in statistics. The multiplicative gamma process takes a relevant step in this direction, but improved studies on its properties are required to ease implementation. This note ... More
Global bifurcation analysis of mean field equations and the Onsager microcanonical description of two-dimensional turbulenceSep 14 2016Oct 21 2016On strictly starshaped domains of second kind we find natural sufficient conditions which allow the solution of two long standing open problems closely related to the mean field equation $\prl$ below. On one side we catch the global behaviour of the Entropy ... More
On the orbital stability of standing-waves solutions to a coupled non-linear Klein-Gordon equationSep 13 2010May 29 2011We consider a system of two coupled non-linear Klein-Gordon equations. We show the existence of standing waves solutions and the existence of a Lyapunov function for the ground state.
Sharp estimate on the first eigenvalue of the p-Laplacian on compact manifold with nonnegative Ricci curvatureFeb 02 2011Jan 07 2014We prove the sharp estimate on the first nonzero eigenvalue of the p-laplacian on a compact Riemannian manifold with nonnegative Ricci curvature and possibly with convex boundary (in this case we assume Neumann b.c. on the p-laplacian). The proof is based ... More
The invariably generating graph of the alternating and symmetric groupsJun 26 2017Given a finite group $G$, the invariably generating graph of $G$ is defined as the undirected graph in which the vertices are the nontrivial conjugacy classes of $G$, and two classes are connected if and only if they invariably generate $G$. In this paper ... More
On short expressions for cosets of permutation subgroupsMay 30 2018Oct 22 2018Following Babai's algorithm for the string isomorphism problem, we determine that it is possible to write expressions of short length describing certain permutation cosets, including all permutation subgroups; this is feasible both in the original version ... More
Universal Lefschetz fibrations and Lefschetz cobordismsMar 10 2014Feb 24 2016We construct universal Lefschetz fibrations, defined in analogy with classical universal bundles. We also introduce the cobordism groups of Lefschetz fibrations, and we see how these groups are quotients of the singular bordism groups via the universal ... More
Positive proportion of short intervals containing a prescribed number of primesDec 31 2018We will prove that for every $m\geq 0$ there exists an $\varepsilon=\varepsilon(m)>0$ such that if $0<\lambda<\varepsilon$ and $x$ is sufficiently large in terms of $m$ and $\lambda$, then $$|\lbrace n\leq x: |[n,n+\lambda\log n]\cap \mathbb{P}|=m\rbrace|\gg_{m,\lambda} ... More
Representing Dehn twists with branched coveringsOct 01 2007Aug 02 2008We show that any homologically non-trivial Dehn twist of a compact surface F with boundary is the lifting of a half-twist in the braid group B_n, with respect to a suitable branched covering p : F -> B^2. In particular, we allow the surface to have disconnected ... More
Modular Covariance, PCT, Spin and StatisticsJul 05 1995The notion of modular covariance is reviewed and the reconstruction of the Poincar\'e group extended to the low-dimensional case. The relations with the PCT symmetry and the Spin and Statistics theorem are described.
TeV sky versus AUGER one: are UHECR also radioactive, heavy galactic nuclei?Dec 30 2011Jan 24 2012UHECR (Ultra High Cosmic Rays) made by He-like lightest nuclei might solve the AUGER extragalactic clustering along Cen A: He UHECR cannot arrive from Virgo because the light nuclei fragility and opacity above few Mpc; UHECR signals are clustering along ... More
Gamma Ray Burst and Soft Gamma Repeaters. Spinning, Precessing Gamma JetsJun 28 1999Gamma Ray Bursts as recent GRB990123 and GRB990510 are observed to occur in cosmic volumes with a corresponding output reaching, for isotropic explosions, energies as large as two solar masses annihilation. These energies are underestimated because of ... More
On the nature of the GRBs-SGRs blazing jetMar 29 1999Aug 04 1999Gamma Ray Burst and Soft Gamma Repeaters are neither standard candle nor isotropic explosions. Our model explain them as strong blazing of a light-house, spinning and precessing gamma jet. Such jets at maximal output (as GRBs in Supernova like sources ... More
X Ray Precursors in GRBs and SGRs: outer X tails around a Precessing Gamma JetNov 22 2000Nov 27 2000Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB, and also rare Soft Gamma Repeaters, SGR, events are in disagreement with any Fireball, or Magnetar, scenarios. These models are originated by an unique explosive event leading, ... More
Discovering Ultra High Energy Neutrinos by Horizontal and Upward tau Air-Showers: Evidences in Terrestrial Gamma Flashes?Feb 24 2000May 18 2010Ultra high energy neutrinos UHE neutrino Tau, anti-neutrino Tau, anti-neutrino electron at PeVs, and higher energy may induce tau air-showers whose detectability is million to billion times amplified by their secondaries. We considered UHE nu_{tau}- N ... More
A Strong Electroweak Sector with Decoupling at Low EnergyAug 12 1997The phenomenology at future hadron colliders of a model with strong interacting vector and axial vector bosons possessing a discrete symmetry demanding mass degeneracy is presented.
Quaternionic Kähler Reductions of Wolf SpacesAug 14 2006The main purpose of the following article is to introduce a \emph{Lie theoretical} approach to the problem of classifying pseudo quaternionic-K\"ahler (QK) reductions of the pseudo QK symmetric spaces, otherwise called \emph{generalized Wolf spaces}.
Hopfian $\ell$-groups, MV-algebras and AF C$^*$-algebrasSep 10 2015An algebra is said to be hopfian if it is not isomorphic to a proper quotient of itself. We describe several classes of hopfian and of non-hopfian unital lattice-ordered abelian groups and MV-algebras. Using Elliott classification and $K_0$-theory, we ... More
Competition/Enhancement of Two Probe Order Parameters in the Unbalanced Holographic SuperconductorFeb 28 2013Mar 02 2013We introduce and study a simple unbalanced holographic superconductor model with two scalar order parameters. The attention is focused on the possibility of coexisting orderings corresponding to the concomitant condensation of two scalar operators. Through ... More
Trapping Electromagnetic Solitons in CylindersApr 03 2013Electromagnetic waves, in vacuum or dielectrics, can be confined in unbounded cylinders in such a way that they turn around the main axis. For particular choices of the cylinder's section, interesting stationary configurations may be assumed. By refining ... More
Numerical Simulation of Electromagnetic Solitons and their Interaction with MatterDec 14 2009A suitable correction of the Maxwell model brings to an enlargement of the space of solutions, allowing for the existence of solitons in vacuum. We review the basic achievements of the theory and discuss some approximation results based on an explicit ... More
Electromagnetic Radiations as a Fluid FlowNov 25 2009We combine Maxwell's equations with Eulers's equation, related to a velocity field of an immaterial fluid, where the density of mass is replaced by a charge density. We come out with a differential system able to describe a relevant quantity of electromagnetic ... More
Robinson-Schensted-Knuth correspondence in the geometry of partial flag varietiesApr 19 2010Apr 21 2010In this paper we generalize to the case of partial flags a result proved both by Spaltenstein and by Steinberg that relates the relative position of two complete flags and the irreducible components of the flag variety in which they lie, using the Robinson-Schensted-Knuth ... More
An Optimally Weighted Estimator of the Linear Power Spectrum Disentangling the Growth of Density Perturbations Across Galaxy SurveysDec 02 2016Measuring the clustering of galaxies from surveys allows us to estimate the power spectrum of matter density fluctuations, thus constraining cosmological models. This requires careful modelling of observational effects to avoid misinterpretation of data. ... More
Notes on well-distributed minimal sub-BIBDs for $λ=1$Mar 28 2018Sep 05 2018In these notes we investigate BIBDs with $\lambda=1$ that present subdesigns evenly covering both blocks and vertices: we determine some of their basic properties, consequence of already existing results in the literature, with regards to their size and ... More
GRBs and SGRs as precessing gamma jetsAug 03 1998The GRB980425-SN1998bw association put in severe strain and contradiction the simplest "candle" fireball model for GRBs. We probed that statistically the association is reliable, the energy luminosity and probability puzzles between cosmic and near by ... More
A Strong Electroweak Sector at Future CollidersOct 31 2002A brief overview of the production at future colliders of two new triplets of spin one resonances from a strong electroweak breaking is presented.
Degenerate BESS model at future collidersOct 05 2001A brief overview of the sensitivity of future colliders to new vector particles from strongly interacting Higgs is presented. In particular the capability of detecting almost degenerate resonances is reviewed.
Non Linear Breaking of the Electroweak Symmetry and Large Extra DimensionsDec 04 2000We consider the coupling to gravity in 4+delta dimensions of a non linear electroweak symmetry breaking sector, with delta compactified dimensions, and derive an effective lagrangian by integrating over the KK excitations of the graviton and of the dilaton. ... More
Degenerate BESS at future $e^+e^-$ collidersJan 16 1996The sensitivity of future $e^+e^-$ colliders to the new physics deriving from a model of strong electroweak symmetry breaking is discussed. The model considered is an effective lagrangian description of Goldstone bosons and of new vector resonances degenerate ... More
Radiation from quantum weakly dynamical horizons in LQGApr 03 2012Using the recent thermodynamical study of isolated horizons by Ghosh and Perez, we provide a statistical mechanical analysis of isolated horizons near equilibrium in the grand canonical ensemble. By matching the description of the dynamical phase in terms ... More
On concordances in 3-manifoldsFeb 17 2016Nov 16 2016We describe an action of the concordance group of knots in the three-sphere on concordances of knots in arbitrary 3-manifolds. As an application we define the notion of almost-concordance between knots. After some basic results, we prove the existence ... More
An Introduction to Resurgence, Trans-Series and Alien CalculusNov 13 2014Jan 17 2015In these notes we give an overview of different topics in resurgence theory from a physics point of view, but with particular mathematical flavour. After a short review of the standard Borel method for the resummation of asymptotic series, we introduce ... More
The mirabolic Hecke algebraOct 14 2013The Iwahori-Hecke algebra of the symmetric group is the convolution algebra of $\gl_n$-invariant functions on the variety of pairs of complete flags over a finite field. Considering convolution on the space of triples of two flags and a vector we obtain ... More
Magnetic fields in neutron starsOct 03 2013This work aims at studying how magnetic fields affect the observational properties and the long-term evolution of isolated neutron stars, which are the strongest magnets in the universe. The extreme physical conditions met inside these astronomical sources ... More
Group Field Theory and Loop Quantum GravityAug 29 2014We introduce the group field theory formalism for quantum gravity, mainly from the point of view of loop quantum gravity, stressing its promising aspects. We outline the foundations of the formalism, survey recent results and offer a perspective on future ... More
A note on Grid Homology in lens spaces: $\mathbb{Z}$ coefficients and computationsOct 24 2015We present a combinatorial proof for the existence of the sign refined Grid Homology in lens spaces, and a self contained proof that $\partial_\mathbb{Z}^2 = 0$. We also present a Sage program that computes $\widehat{GH} (L(p,q),K;\mathbb{Z})$, and provide ... More
Analytical computation of stray light in nested mirror modules for X-ray telescopesSep 30 2016Stray light in X-ray telescopes is a well-known issue. Unlike rays focused via a double reflection by usual grazing-incidence geometries such as the Wolter-I, stray rays coming from off-axis sources are reflected only once by either the parabolic or the ... More
Even and odd instanton bundles on Fano threefolds of Picard number 1Sep 18 2011Apr 10 2013We consider an analogue of the notion of instanton bundle on the projective 3-space, consisting of a class of rank-2 vector bundles defined on smooth Fano threefolds X of Picard number one, having even or odd determinant according to the parity of K_X. ... More
A geometric construction of Tango bundle on P^5Nov 19 2001Nov 20 2001The Tango bundle T over P^5 is proved to be the pull-back of the twisted Cayley bundle C(1) via a map f : P^5 --> Q_5 existing only in characteristic 2. The Frobenius morphism F factorizes via such f. Using f the cohomology of T is computed in terms of ... More
Minimal Model for an Unbalanced Holographic SuperconductorApr 22 2013We describe the simplest holographic model for an s-wave unbalanced superconductor in 2+1 dimensions. We study its phase diagram and linear response features with particular attention to the possibility of spatially modulated phases (LOFF) and mixed spin-electric ... More
D-branes and Non-Perturbative Quantum Field Theory: Stringy Instantons and Strongly Coupled SpintronicsOct 20 2012The non-perturbative dynamics of quantum field theories is studied using theoretical tools inspired by string formalism. Two main lines are developed: the analysis of stringy instantons in a class of four-dimensional N=2 gauge theories and the holographic ... More
Charging Capacitors According to Maxwell's Equations: ImpossibleNov 02 2014The charge of an ideal parallel capacitor leads to the resolution of the wave equation for the electric field with prescribed initial conditions and boundary constraints. Independently of the capacitor's shape and the applied voltage, none of the corresponding ... More
A Lagrangian for Electromagnetic Solitary Waves in VacuumAug 12 2010A system of equations, describing the evolution of electromagnetic fields, is introduced and discussed. The model is strictly related to Maxwell's equations. As a matter of fact, the Lagrangian is the same, but the variations are subjected to a suitable ... More
The Fractal Structure of Matter and the Casimir EffectJun 10 2009The zero-point radiation is an electromagnetic form of energy pervading the universe. Its existence is granted by standard quantum theories. We provide here an explanation based on deterministic classical electrodynamics, by associating to particles and ... More
From Photons to Atoms - The Electromagnetic Nature of MatterMay 07 2012Motivated by a revision of the classical equations of electromagnetism that allow for the inclusion of solitary waves in the solution space, the material collected in these notes examine the consequences of adopting the modified model in the description ... More
On power-counting renormalizability of Hořava gravity with detailed balanceFeb 23 2015Jun 12 2015We consider the version of Ho\v{r}ava gravity where "detailed balance" is consistently implemented, so as to limit the huge proliferation of couplings in the full theory and obtain healthy dynamics at low energy. Since a superpotential which is third-order ... More
Homology of the three flag Hilbert schemeSep 16 2016We prove the existence of an affine paving for the three-step flag Hilbert scheme $$ \text{Hilb}^{n, n+1, n+2}(0) := \left\{\mathbb{C}[[x,y]]\supset I_n\supset I_{n+1}\supset I_{n+2}: I_i \,\,\text{ ideals with } \text{dim}_{\mathbb{C}} {\mathbb{C}[x,y]}/{I_i} ... More
An Observational Study: The Effect of Diuretics Administration on Outcomes of Mortality and Mean Duration of I.C.U. StayAug 11 2014This thesis conducts an observational study into whether diuretics should be administered to ICU patients with sepsis when length of stay in the ICU and 30-day post-hospital mortality are considered. The central contribution of the thesis is a stepwise, ... More
Equidistant liftings of elementary abelian Galois covers of curvesOct 21 2015May 12 2016In this paper, we discuss the local lifting problem for the action of elementary abelian groups. Studying logarithmic differential forms linked to deformations of $(\mu_p)^n$-torsors, we show necessary conditions on the set of ramification points in order ... More
Generalized external cone condition for domains in Riemannian manifoldsFeb 10 2010Apr 09 2015The aim of this note is to present an alternative proof for an already known result relative to the solvability of the Dirichlet problem in Riemannian manifolds (see remark 0.1). In particular, we discuss the p-regularity (regularity relative to the p-laplacian) ... More
On the spectral flow for paths of essentially hyperbolic bounded operators on Banach spacesJun 25 2008Mar 09 2011We give a definition of the spectral flow for paths of bounded essentially hyperbolic operators on a Banach space. The spectral flow induces a group homomorphism on the fundamental group of every connected component of the space of essentially hyperbolic ... More
Fans and generators of free abelian l-groupsJul 03 2015Let $t_1,\ldots,t_n$ be $\ell$-group terms in the variables $X_1,\ldots,X_m$. Let $\hat t_1,\ldots,\hat t_n$ be their associated piecewise homogeneous linear functions. Let $G $ be the $\ell$-group generated by $\hat t_1, \ldots,\hat t_n$ in the free ... More
Liouville theorem, conformally invariant cones and umbilical surfaces for Grushin-type metricsJul 06 2006Apr 27 2009We prove a classification theorem for conformal maps with respect to the control distance generated by a system of diagonal vector fields. It turns out that all such maps can be obtained as compositions of suitable dilations, inversions and isometries. ... More
The Weisfeiler-Leman algorithm and the diameter of Schreier graphsJul 05 2017Sep 05 2018We prove that the number of iterations taken by the Weisfeiler-Leman algorithm for configurations coming from Schreier graphs is closely linked to the diameter of the graphs themselves: an upper bound is found for general Schreier graphs, and a lower ... More
A first study of the semi-leptonic decay of the $Λ_b$ baryonJul 29 1996We present the preliminary results of the first Lattice study of the baryonic Isgur and Wise function obtained from the matrix element of the weak current between $\Lambda$-baryon external states. Its dependence on the heavy and light quark masses is ... More
Heavy Baryon SpectroscopyNov 30 1994We present the preliminary results of an exploratory study of heavy baryon spectroscopy, using the $O(a)$-improved fermionic action. Estimates of masses and splittings at the charm and beauty physical limit are reported.
Compacton formation under Allen--Cahn dynamicsFeb 25 2016We study the solutions of a generalized Allen-Cahn equation deduced from a Landau energy functional, endowed with a non-constant higher order stiffness. We analytically solve the stationary problem and deduce the existence of so-called compactons, namely, ... More
Global bifurcation analysis of mean field equations and the Onsager microcanonical description of two-dimensional turbulenceSep 14 2016On strictly starshaped domains of second kind we find natural sufficient conditions which allow the solution of two long standing open problems closely related to the mean field equation $\prl$ below. On one side we catch the global behaviour of the Entropy ... More
Conjugate flow action functionalsOct 13 2011Oct 15 2013We present a new general method to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations of the theory relative to a diffeomorphic flow of curvilinear coordinates which is assumed ... More
Tests for a Strong Electroweak Sector at Future e^+e^- High Energy CollidersNov 19 1997Feb 09 1998The study of the scattering at high energy of the gauge bosons W and Z, in particular longitudinally polarized W and Z, can clarify the mechanism of spontaneous symmetry breaking in the Standard Model of the electroweak interactions. Different models ... More
Apart Cen A are UHECR mostly heavy radioactive and galactic nuclei?Dec 29 2011Feb 28 2012Earliest AUGER UHECR anisotropy correlated with AGN within a GZK Universe almost fade away. Recent UHECR mass compositions did show a negligible nucleon composition and an UHECR nuclei (light or heavy) signature. The absence of UHECR events toward the ... More
GRBs by thin persistent precessing lepton Jets: the long life GRB110328 and the Neutrino signalAug 02 2011Mar 29 2012Gamma Ray Burst sources are apparently evolving around us in a harder and brighter samples at far and far redshift. The average output may range from a near Supernova (nearest events) output to a billion time that power for most distant events. Such a ... More
Tau air showers detectability with GLASTJun 12 2008We show that with GLAST there will be the possibility to detect, within the UHECR skimming at atmosphere edges, the showers generated by very high energy upward and horizontal Tau. The effective area, thanks to the large area covered by the showers at ... More
Arrays is Space to detect Upward Tau and Highest Altitude ShowersJul 05 2001Ultra High Energy, UHE, upward Tau neutrinos Tau, anti-neutrino Tau, above hundred TeVs and up to tens PeV energies, of relevant astrophysical nature, may lead to UHE Taus and consequent Up-ward Tau air-Showers {UPTAUS} after interaction on Earth crust ... More
Tau Air-Showers Signature of Ultra High Energy NeutrinosJan 31 2001The discover of Ultra High Energy Neutrino of astrophysical nature may be already reached. Indeed upward and horizontal tau Air-showers emerging from the Earth crust or mountain chains offer the best and most powerful signal of Ultra High Energy UHE neutrinos ... More
Neutrino Solar Flare detection for a saving alert system of satellites and astronautsJun 19 2011Largest Solar Neutrino Flare may be soon detectable by Deep Core neutrino detector immediately and comunicate to satellites or astronauts. Its detection is the fastest manifestation of a later (tens minutes,hours) dangerous cosmic shower. The precursor ... More