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Extreme eigenvalues of sparse, heavy tailed random matricesJun 19 2015We study the statistics of the largest eigenvalues of $p \times p$ sample covariance matrices $\Sigma_{p,n} = M_{p,n}M_{p,n}^{*}$ when the entries of the $p \times n$ matrix $M_{p,n}$ are sparse and have a distribution with tail $t^{-\alpha}$, $\alpha>0$. ... More

On properties of Parisi measuresMar 14 2013We investigate the structure of Parisi measures, the functional order parameters of mixed p-spin models in mean field spin glasses. In the absence of external field, we prove that a Parisi measure satisfies the following properties. First, at all temperatures, ... More

Parisi formula for the ground state energy in the mixed p-spin modelJun 16 2016Jun 28 2016We show that the thermodynamic limit of the ground state energy in the mixed p-spin model can be identified as a variational problem. This gives a natural generalization of the Parisi formula at zero temperature.

The Parisi formula has a unique minimizerFeb 20 2014Sep 05 2014In 1979, G. Parisi predicted a variational formula for the thermodynamic limit of the free energy in the Sherrington-Kirkpatrick model and described the role played by its minimizer. This formula was verified in the seminal work of Talagrand and later ... More

Universality of chaos and ultrametricity in mixed p-spin modelsOct 29 2014We prove disorder universality of chaos phenomena and ultrametricity in the mixed p-spin model under mild moment assumptions on the environment. This establishes the long-standing belief among physicists that the Parisi solution in mean-field models is ... More

On concentration properties of disordered HamiltoniansJun 26 2017We present an elementary approach to concentration of disordered Hamiltonians. Assuming differentiability of the limiting free energy $F$ with respect to the inverse temperature $\beta$, we show that the Hamiltonian concentrates around the energy level ... More

Free energy and complexity of spherical bipartite modelsMay 09 2014We investigate both free energy and complexity of the spherical bipartite spin glass model. We first prove a variational formula in high temperature for the limiting free energy based on the well-known Crisanti-Sommers representation of the mixed p-spin ... More

The Legendre structure of the Parisi formulaOct 12 2015Oct 26 2015We show that the Parisi formula of the mixed $p$-spin model is a concave function of the squared inverse temperature. This allows us to derive a new expression for the Parisi formula that involves the inverse temperature and the Parisi measure as Legendre ... More

Topologies of random geometric complexes on Riemannian manifolds in the thermodynamic limitDec 21 2018We investigate the topologies of random geometric complexes built over random points sampled on Riemannian manifolds in the so-called "thermodynamic" regime. We prove the existence of universal limit laws for the topologies; namely, the random normalized ... More

Universality for directed polymers in thin rectanglesApr 19 2012Apr 26 2012We consider the fluctuations of the free energy of positive temperature directed polymers in thin rectangles (N,N^{\alpha}), \alpha < 3/14. For general weight distributions with finite fourth moment we prove that the distribution of these fluctuations ... More

Existence of two-step replica symmetry breaking for the spherical mixed p-spin glass at zero temperatureFeb 08 2018Oct 02 2018We provide the first examples of two-step replica symmetry breaking (2-RSB) models for the spherical mixed p-spin glass at zero temperature. Precisely, we show that for a certain class of mixtures, the Parisi measure at zero temperature is purely atomic ... More

Directed polymers in random environment with heavy tailsJan 07 2010We study the model of Directed Polymers in Random Environment in 1+1 dimensions, where the distribution at a site has a tail which decays regularly polynomially with power \alpha, where \alpha \in (0,2). After proper scaling of temperature \beta^{-1}, ... More

Existence of two-step replica symmetry breaking for the spherical mixed p-spin glass at zero temperatureFeb 08 2018We provide the first examples of two-step replica symmetry breaking (2-RSB) models for the spherical mixed p-spin glass at zero temperature. Precisely, we show that for a certain class of mixtures, the Parisi measure at zero temperature is purely atomic ... More

On the time constant of high dimensional first passage percolationJan 28 2016We study the time constant $\mu(e_{1})$ in first passage percolation on $\mathbb Z^{d}$ as a function of the dimension. We prove that if the passage times have finite mean, $$\lim_{d \to \infty} \frac{\mu(e_{1}) d}{\log d} = \frac{1}{2a},$$ where $a \in ... More

On spin distributions for generic p-spin modelsFeb 20 2018Feb 22 2018We provide an alternative formula for spin distributions of generic p-spin glass models. As a main application of this expression, we write spin statistics as solutions of partial differential equations and we show that the generic p-spin models satisfy ... More

Differentiability at the edge of the percolation cone and related results in first-passage percolationMay 20 2011Feb 28 2012We study first-passage percolation in two dimensions, using measures mu on passage times with b:=inf supp(mu) >0 and mu({b})=p \geq p_c, the threshold for oriented percolation. We first show that for each such mu, the boundary of the limit shape for mu ... More

Complexity of random smooth functions on the high-dimensional sphereOct 26 2011Dec 16 2013We analyze the landscape of general smooth Gaussian functions on the sphere in dimension $N$, when $N$ is large. We give an explicit formula for the asymptotic complexity of the mean number of critical points of finite and diverging index at any level ... More

On the energy landscape of spherical spin glassesFeb 28 2017Mar 10 2017We investigate the energy landscape of the spherical mixed even p-spin model near its maximum energy. We relate the distance between pairs of near maxima to the support of the Parisi measure at zero temperature. We then provide an algebraic relation that ... More

A duality principle in spin glassesMay 05 2016May 13 2016We prove a duality principle that connects the thermodynamic limits of the free energies of the Hamiltonians and their squared interactions. Under the main assumption that the limiting free energy is concave in the squared temperature parameter, we show ... More

A duality principle in spin glassesMay 05 2016May 22 2017We prove a duality principle that connects the thermodynamic limits of the free energies of the Hamiltonians and their squared interactions. Under the main assumption that the limiting free energy is concave in the squared temperature parameter, we show ... More

50 years of first passage percolationNov 10 2015Sep 23 2016We celebrate the 50th anniversary of one the most classical models in probability theory. In this survey, we describe the main results of first passage percolation, paying special attention to the recent burst of advances of the past 5 years. The purpose ... More

BlackHawk: A public code for calculating the Hawking evaporation spectra of any black hole distributionMay 10 2019We describe BlackHawk, a public C program for calculating the Hawking evaporation spectra of any black hole distribution. This program enables the users to compute the primary and secondary spectra of stable or long-lived particles generated by Hawking ... More

Poisson convergence for the largest eigenvalues of Heavy Tailed Random MatricesOct 16 2007May 07 2008We study the statistics of the largest eigenvalues of real symmetric and sample covariance matrices when the entries are heavy tailed. Extending the result obtained by Soshnikov in \cite{Sos1}, we prove that, in the absence of the fourth moment, the top ... More

The SK model is Full-step Replica Symmetry Breaking at zero temperatureMar 20 2017We prove that the Parisi measure of the mixed p-spin model at zero temperature has infinitely many points in its support. This establishes Parisi's prediction that the functional order parameter of the Sherrington-Kirkpatrick model is not a step function ... More

Random Matrices and complexity of Spin GlassesMar 04 2010Nov 07 2011We give an asymptotic evaluation of the complexity of spherical p-spin spin-glass models via random matrix theory. This study enables us to obtain detailed information about the bottom of the energy landscape, including the absolute minimum (the ground ... More

Linear growth of streaming instability in pressure bumpsSep 25 2017Streaming instability is a powerful mechanism which concentrates dust grains in pro- toplanetary discs, eventually up to the stage where they collapse gravitationally and form planetesimals. Previous studies inferred that it should be ineffective in viscous ... More

Cosmic $ΔB$ from Lepton Violating Interactions at the Electroweak Phase TransitionJun 05 1992We propose a new mechanism for late cosmological baryon asymmetry in models with first order electroweak phase transition. Lepton asymmetry arises through the decay of particles produced out of equilbrium in bubble collisions and is converted into baryon ... More

Existence and convexity of solutions of the fractional heat equationJun 01 2016Aug 22 2017We prove that the initial-value problem for the fractional heat equation admits a solution provided that the (possibly unbounded) initial datum has a conveniently moderate growth at infinity. Under the same growth condition we also prove that the solution ... More

The QCD potential at O(1/m^2): Complete spin-dependent and spin-independent resultSep 12 2000Apr 11 2001Within an effective field theory framework, we obtain an expression, with O(1/m^2) accuracy, for the energies of the gluonic excitations between heavy quarks, which holds beyond perturbation theory. For the singlet heavy quark--antiquark energy, in particular, ... More

Sign-changing solutions of the fractional heat equation: existence and convexityJun 01 2016We prove that the initial-value problem for the fractional heat equation admits a solution provided that the (possibly unbounded) initial datum has a conveniently moderate growth at infinity. Under the same growth condition we also prove that the solution ... More

Topological invariants of O'Grady's six dimensional irreducible symplectic varietyJun 02 2004Aug 08 2004We study O'Grady examples of irreducible symplectic varieties: we establish that both of them can be deformed into lagrangian fibrations. We analyse in detail the topology of the six dimensional example: in particular we compute its Euler characteristic ... More

Distributed Space-Time Coding of Over-the-Air Superimposed Packets in Wireless NetworksMar 14 2013In this paper we propose a new cooperative packet transmission scheme that allows independent sources to superimpose over-the-air their packet transmissions. Relay nodes are used and cooperative diversity is combined with distributed space-time block ... More

General Covariance, Diffeomorphism Invariance, and Background Independence in 5 DimensionsOct 04 2014Apr 10 2015The paper considers the "GR-desideratum", that is, the way general relativity implements general covariance, diffeomorphism invariance, and background independence. Two cases are discussed where $5$-dimensional generalizations of general relativity run ... More

Darboux polynomial matrices: the classical Massive Thirring Model as study caseNov 28 2014One way of constructing explicit expressions of solutions of integrable systems of Partial Differential Equations (PDEs) goes via the Darboux method. This requires the construction of Darboux matrices. Here we introduce a novel algorithm to obtain such ... More

Plenty of Morse functions by perturbing with sums of squaresNov 16 2011Given a smooth function f on R^n and a submanifold M, we prove that the set of diagonal quadratic forms q such that the restriction of f+q to M is Morse is a dense set (in the n-dimensional space of diagonal quadratic forms). The standard transversality ... More

Convex pencils of real quadratic formsJun 23 2011Sep 06 2012We study the topology of the set X of the solutions of a system of two quadratic inequalities in the real projective space RP^n (e.g. X is the intersection of two real quadrics). We give explicit formulae for its Betti numbers and for those of its double ... More

Inflation and the Theory of Cosmological PerturbationsOct 10 2002These lectures provide a pedagogical introduction to inflation and the theory of cosmological perturbations generated during inflation which are thought to be the origin of structure in the universe.

The More Relaxed Supersymmetric Electroweak BaryogenesisMar 15 1998We reanalyze the issue of generation of the baryon asymmetry at the electroweak phase transition in the MSSM and compute the baryon asymmetry assuming the presence of non-trivial CP-violating phases in the parameters associated with the left-right stop ... More

Effective field theories for baryons with two- and three-heavy quarksAug 26 2010Oct 28 2010Baryons made of two or three heavy quarks can be described in the modern language of non-relativistic effective field theories. These, besides allowing a rigorous treatment of the systems, provide new insight in the nature of the three-body interaction ... More

Non-relativistic bound states: the long way back from the Bethe-Salpeter to the Schroedinger equationFeb 19 2009Apr 06 2009I review, in a personal perspective, the history of the theory of non-relativistic bound states in QED and QCD from the Bethe-Salpeter equation to the construction of effective field theories.

Heavy quarkonium decays and transitions in the language of effective field theoriesDec 30 2005Heavy quarkonium decays and transitions are discussed in the framework of non-relativistic effective field theories. Emphasis is put on the matching procedure in the non-perturbative regime. Some exact results valid for the magnetic dipole couplings are ... More

Open Problems in Heavy Quarkonium PhysicsDec 22 2004Some recent progress and a personal selection of open problems in heavy quarkonium physics (spectroscopy, decay and production) inspired by the activity of the Quarkonium Working Group are reviewed.

The QCD potentialSep 21 2007After reviewing the definition of the heavy quark-antiquark potential in pNRQCD, we discuss recent advances in the calculation.

Asymmetric random walks in a discrete spacetime as a model for quantum mechanicsDec 20 2013Jan 25 2015This paper presents a simple model that mimics quantum mechanics (QM) results in terms of probability fields of free particles subject to self-interference, without using Schr\"{o}dinger equation or wavefunctions. Unlike the standard QM picture, the proposed ... More

Dynamics and (de)localization in a one-dimensional tight-binding chainJul 18 2006A simple tight-binding model is used to illustrate how the time dependence of a state vector can be obtained from all the eigenvalues and eigenvectors of the Hamiltonian. The behavior of the eigenvalues and eigenvectors is studied for various parameters ... More

Energies of sp2 carbon shapes with pentagonal disclinations and elasticity theoryMar 28 2006Jun 26 2006Energies of a certain class of fullerene molecules (elongated, contracted, and regular icosahedral fullerenes) are numerically calculated using a microscopic description of carbon-carbon bonding. It is shown how these results can be interpreted and comprehended ... More

Adsorption of He atoms in external grooves of single wall carbon nanotube bundlesNov 15 2002I calculate the quantum states for He atom in the potential of an external groove of the single wall carbon nanotube bundle. The calculated ground state energy is found to be in fair agreement with the experimental estimate which suggests that the outer ... More

Icosadeltahedral geometry of fullerenes, viruses and geodesic domesNov 22 2007I discuss the symmetry of fullerenes, viruses and geodesic domes within a unified framework of icosadeltahedral representation of these objects. The icosadeltahedral symmetry is explained in details by examination of all of these structures. Using Euler's ... More

Constraining hybrid inflation models with WMAP three-year resultsOct 03 2006Jan 11 2007We reconsider the original model of quadratic hybrid inflation in light of the WMAP three-year results and study the possibility of obtaining a spectral index of primordial density perturbations, $n_s$, smaller than one from this model. The original hybrid ... More

Hint of non-standard dynamics in solar neutrino conversionJan 20 2011Apr 27 2011Motivated by the recent low-threshold measurements of the solar 8B neutrino spectrum performed by Borexino, Super-Kamiokande and the Sudbury Neutrino Observatory -- all now monitoring the transition regime between low-energy (vacuum-like) and high-energy ... More

An estimate of theta_14 independent of the reactor antineutrino flux determinationsJan 20 2012Mar 08 2012In a previous paper [Phys. Rev. D 83, 113013 (2011)] we have shown that the solar sector data (solar and KamLAND) are sensitive to the parameter theta_14, encoding the admixture of the electron neutrino with a fourth (essentially) sterile mass eigenstate. ... More

Hodographic VorticesAug 08 2008Jul 10 2009Vortices are screw phase dislocations associated with helicoidal wave-fronts. In nonlinear optics, vortices arise as singular solutions to the phase-intensity equations of geometric optics. They exist for a general class of nonlinear response functions. ... More

A discrete spacetime model for quantum mechanicsJun 02 2015This paper presents a simple model that mimics quantum mechanics (QM) results in terms of probability fields of free particles subject to self-interference, without using Schroedinger equation or complex wavefunctions. Unlike the standard QM picture, ... More

ICHEP 2014 Summary: Theory Status after the First LHC RunMay 07 2015Jun 08 2015A brief overview of the main highlights discussed at ICHEP 2014 is presented. The experimental data confirm that the scalar boson discovered at the LHC couples to other particles as predicted in the Standard Model. This constitutes a great success of ... More

Quantifying the dynamical complexity of time seriesOct 19 2016A powerful tool is developed for the characterization of chaotic signals. The approach is based on the symbolic encoding of time series (according to their ordinal patterns) combined with the ensuing characterization of the corresponding cylinder sets. ... More

Spectroscopic investigations of phonons in epitaxial grapheneJan 04 2016The interaction of graphene with metallic substrates reveals phenomena and properties of great relevance for applications in nanotechnology. In this review, the vibrational characterization by means of various inelastic scattering spectroscopies are surveyed ... More

Can Bohmian Mechanics Be Made Background Independent?Sep 02 2015The paper presents an inquiry into the question regarding the compatibility of Bohmian mechanics, intended as a non-local theory of moving point-like particles, with background independence. This issue is worth being investigated because, if the Bohmian ... More

Proper holomorphic Legendrian curves in $SL_2(\mathbb{C})$Nov 02 2016In this paper we prove that every open Riemann surface properly embeds in the Special Linear group $SL_2(\mathbb{C})$ as a holomorphic Legendrian curve, where $SL_2(\mathbb{C})$ is endowed with its standard contact structure. As a consequence, we derive ... More

Asymptotic cosmological solutions for string/brane gases with solitonic fluxesJan 13 2005We present new cosmological solutions for brane gases with solitonic fluxes that can dynamically explain the existence of three large spatial dimensions. This reasserts the importance of fluxes for understanding the full space of solutions in a potential ... More

The number of weakly compact sets which generate a Banach spaceFeb 28 2009We consider the cardinal invariant CG(X) of the minimal number of weakly compact subsets which generate a Banach space X. We study the behavior of this index when passing to subspaces, its relation with the Lindelof number in the weak topology and other ... More

k-Colorability is Graph Automaton RecognizableJan 21 2014Automata operating on general graphs have been introduced by virtue of graphoids. In this paper we construct a graph automaton that recognizes $k$-colorable graphs.

A Topological Approach to Spectral ClusteringJun 08 2015We propose a clustering algorithm which, for input, takes data assumed to be sampled from a uniform distribution supported on a metric space $X$, and outputs a clustering of the data based on a topological estimate of the connected components of $X$. ... More

Lagrangian blow-ups, blow-downs, and applications to real packingDec 05 2010Dec 07 2012Given a symplectic manifold (M, {\omega}) and a Lagrangian submanifold L, we construct versions of the symplectic blow-up and blow-down which are defined relative to L. Furthermore, we show that if M admits an anti-symplectic involution {\phi} and we ... More

A Local-Realistic Model of Quantum Mechanics Based on a Discrete Spacetime (Extended version)Dec 08 2017This paper presents a realistic, stochastic, and local model that reproduces nonrelativistic quantum mechanics (QM) results without using its mathematical formulation. The proposed model only uses integer-valued quantities and operations on probabilities, ... More

Classes of structures with no intermediate isomorphism problemsSep 16 2013We say that a theory $T$ is intermediate under effective reducibility if the isomorphism problems among its computable models is neither hyperarithmetic nor on top under effective reducibility. We prove that if an infinitary sentence $T$ is uniformly ... More

A fixed point for the jump operator on structuresJun 05 2011Assuming that $0^#$ exists, we prove that there is a structure that can effectively interpret its own jump. In particular, we get a structure $\mathcal A$ such that \[ Sp({\mathcal A}) = \{{\bf x}':{\bf x}\in Sp ({\mathcal A})\}, \] where $Sp ({\mathcal ... More

Experimental results on event shapes at hadron collidersMay 05 2017In this paper a review on event shapes at hadron colliders, mainly focused on experimental results, is presented. Measurements performed at the Tevatron and at the LHC, for the soft and hard regimes of QCD, are reviewed. The potential applications of ... More

On the Lie and Cartan Theory of Invariant Differential Systems, IIIMar 23 2017It is presently our aim to undertake the discussion, of the Parts I and II, on the infinitesimal level and outline as well the transition from infinitesimal to finite, the main reason for this being, of course, the well known fact that arguments and calculation ... More

The unit ball of the Hilbert space in its weak topologyMar 01 2009We show that the unit ball of a Hilbert space in its weak topology is a continuous image of the countable power of the Alexandroff compactification of a discrete set, and we deduce some combinatorial properties of its lattice of open sets which are not ... More

The Aleph-zero or zero dichotomyApr 18 2008Nov 23 2009This paper proves the existence of a dichotomy which being formally derived from the topological successiveness of w-order leads to the same absurdity of Zeno's Dichotomy II. It also derives a contradictory result from the first Zeno's Dichotomy.

Transfinite partitions of Jordan curvesAug 21 2006The w-asymmetry induced by transfinite partitions makes it impossible for Jordan curves to have an infinite length.

SuperswappingApr 18 2008Jan 27 2012Supertask theory is used here to prove a contradictory result which involves the consistency of w-order and the Axiom of Infinity.

Some reflections on variational methods for partial differential inclusionsJan 21 2016We discuss the application of variational methods, based on non-smooth critical point theory, to a general class of partial differential inclusions.

Leptons and QCDDec 12 2014Three important QCD-related aspects of the $\tau$ and $\mu$ dynamics are reviewed: the determination of the strong coupling from the hadronic tau decay width, leading to the updated value $\alpha_s(m_\tau^2) = 0.331 \pm 0.013$; the measurement of $|V_{us}|$ ... More

Quantum field theory of axion-photon mixing and vacuum polarizationApr 25 2019We report on recent results obtained by analyzing axion--photon mixing in the framework of quantum field theory. We obtain corrections to the oscillation formulae and we reveal a new effect of the vacuum polarization due to the non-zero value of the vacuum ... More

Stone-type representations and dualities for varieties of bisemilatticesMar 18 2018In this article we will focus our attention on the variety of distributive bisemilattices and some linguistic expansions thereof: bounded, De Morgan, and involutive bisemilattices. After extending Balbes' representation theorem to bounded, De Morgan, ... More

Tau-decay determination of the strong couplingNov 25 2018We review the current status of the determination of the strong coupling from tau decay. Using the most recent release of the ALEPH data, a very comprehensive phenomenological analysis has been performed, exploring all strategies previously considered ... More

Categorification of tensor powers of the vector representation of $U_q(\mathfrak{gl}(1|1))$May 27 2013Jan 09 2015We consider the monoidal subcategory of finite dimensional representations of $U_q(\mathfrak{gl}(1|1))$ generated by the vector representation, and we provide a diagram calculus for the intertwining operators, which allows to compute explicitly the canonical ... More

Special systems through double points on an algebraic surfaceMay 03 2006Let S be a smooth algebraic surface satisfying the following property: H^i(\oc_S(C))=0 (i=1,2) for any irreducible and reduced curve C of S. The aim of this paper is to provide a characterization of special linear systems on S which are singular along ... More

Regular polyhedra in the 3-torusApr 21 2016In this paper we discuss the classification rank $3$ lattices preserved by finite orthogonal groups of isometries and derive from it the classification of regular polyhedra in the $3$-dimensional torus. This classification is highly related to the classification ... More

A multiplicity result for the nonlinear Klein Gordon Maxwell equationsJul 04 2014Dec 13 2014In this paper we provide a new technique to find solutions to the Klein-Gordon-Maxwell system. The method, based on an iterative argument, permits to improve previous results where the reduction method was used. We also show how this device permits to ... More

The elliptic Kirchhoff equation in $\R^N$ perturbed by a local nonlinearityJan 02 2010Apr 26 2011In this paper we present a very simple proof of the existence of at least one non trivial solution for a Kirchhoff type equation on $\RN$, for $N\ge 3$. In particular, in the first part of the paper we are interested in studying the existence of a positive ... More

CMC hypersurfaces of semi-Riemannian groupsSep 26 2012Jan 01 2014In this paper, we study the geometry of a connected oriented cmc Riemannian hypersurface $M$ of a semi-Riemannian group $G$ of Lie algebra $\mathfrak g$ and index 0 or 1. If $G$ is Riemannian and $M$ is compact and transversal to an element of $\mathfrak ... More

Half-space theorems for properly immersed surfaces in $\mathbb{R}^3$ with prescribed mean curvatureJan 14 2019Motivated by the large ammount of results obtained for minimal and positive constant mean curvature surfaces in several ambient spaces, the aim of this paper is to obtain half-space theorems for properly immersed surfaces in $\mathbb{R}^3$ whose mean ... More

An introduction to the dark energy problemFeb 13 2008In this work we review briefly the origin and history of the cosmological constant and its recent reincarnation in the form of the dark energy component of the universe. We also comment on the fundamental problems associated to its existence and magnitude ... More

Nonlocal low-energy effective action for gravity with torsionDec 21 1997Oct 22 1999In this work we calculate the low-energy effective action for gravity with torsion, obtained after the integration of scalar and fermionic matter fields, using the local momentum representation based on the Riemann normal coordinates expansion. By considering ... More

Confronting hadronic tau decays with non-leptonic kaon decaysNov 16 2018In the chiral limit, the $D=6$ contribution to the Operator Product Expansion (OPE) of the $\mathrm{VV-AA}$ correlator of quark currents only depends on two vacuum condensates, which can be related to hadronic matrix elements associated to CP violation ... More

A Kepler's note on secular inequalitiesFeb 13 2014I discuss the problem of secular inequalities in Kepler by giving account of a manuscript note that has not been published until 1860. In his note Kepler points out the need for a model, clearly inspired by the method of epicycles, that describes the ... More

On minimal models of projective Hyperkaehler manifoldsMar 17 2015Mar 21 2015Any minimal model of a projective Hyperkaehler manifold is a projective Hyperkaehler manifold. As a consequence, moduli spaces of sheaves on a k3 that don't admit a symplectic resolution are not birational to Hyperkaehler manifolds.

Intrinsic volumes of set of singular matricesJan 20 2014We explicitly compute the intrinsic volume of the set of real (and real symmetric) matrices of Frobenius norm one and given corank (the case of matrices with zero determinant as a special case). We give asymptotic formulas for our computations and we ... More

A Possible Cosmological Explanation of why Supersymmetry is hiding at the LHCNov 06 2012If one is not ready to pay a large fine-tuning price within supersymmetric models given the current measurement of the Higgs boson mass, one can envisage a scenario where the supersymmetric spectrum is made of heavy scalar sparticles and much lighter ... More

D-Term Inflation: The Good, the Bad and the UglyOct 13 1997An inflationary stage dominated by a D-term avoids the slow-roll problem of inflation in supergravity and can naturally emerge in theories with a non-anomalous or anomalous U(1) gauge symmetry. In this talk different aspects of D-term inflation are discussed. ... More

Cosmological Implications of Low Energy Supersymmetry Breaking ModelsAug 11 1997Aug 13 1997We show that stable local cosmic strings are a generic prediction of supersymmetric models where supersymmetry is broken at scales within a few orders of magnitude of the weak scale and is fed down to the observable sector by gauge interactions. The typical ... More

A note on the Joint Spectral RadiusFeb 05 2015A brief summary on the properties of the so called Joint Spectral Radius

Heavy Quarkonium Physics from Effective Field TheoriesOct 19 2006I review recent progress in heavy quarkonium physics from an effective field theory perspective. In this unifying framework, I discuss advances in perturbative calculations for low-lying quarkonium observables and in lattice calculations for high-lying ... More

pNRQCD: review of selected resultsOct 17 2000Oct 18 2000I review and discuss a selected sample of recent results in pNRQCD.

Transverse momentum broadening and gauge invarianceSep 20 2012In the framework of the soft-collinear effective theory, we present a gauge invariant definition of the transverse momentum broadening probability of a highly-energetic collinear quark in a medium and consequently of the jet quenching parameter $\hat{q}$. ... More

Effective Field Theories for Quarkonium and Dipole TransitionsSep 12 2011Effective field theories for quarkonium at zero and finite temperature provide an unifying description for a wide class of phenomena. As an example, we discuss physical effects induced by dipole transitions.

Effective field theories for heavy quarkonium at finite temperatureJan 22 2009We discuss the recent development of effective field theories for quarkonium at finite temperature.

Poincare' invariance constraints on non-relativistic effective field theoriesOct 06 2003Mar 18 2011We discuss Poincare' invariance in the context of non-relativistic effective field theories of QCD. We show, in the cases of the HQET and pNRQCD, that the algebra of the generators of the Poincare' transformations imposes precise constraints on the form ... More