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Uncertainty Quantification for Geometry Deformations of Superconducting Cavities using Eigenvalue TrackingFeb 08 2018The electromagnetic field distribution as well as the resonating frequency of various modes in superconducting cavities are sensitive to small geometry deformations. The occurring variations are motivated by measurements of an available set of resonators ... More

Isogeometric Simulation of Lorentz Detuning in Superconducting Accelerator CavitiesJun 27 2016Cavities in linear accelerators suffer from eigenfrequency shifts due to mechanical deformation caused by the electromagnetic radiation pressure, a phenomenon known as Lorentz detuning. Estimating the frequency shift up to the needed accuracy by means ... More

Uncertainty Quantification for Maxwell's Eigenproblem using Isogeometric AnalysisFeb 08 2018May 30 2018The electromagnetic field distribution as well as the resonating frequency of various modes in superconducting cavities used in particle accelerators for example are sensitive to small geometry deformations. The occurring variations are motivated by measurements ... More

Isogeometric Mortar Coupling for Electromagnetic ProblemsDec 27 2018This paper discusses and analyses two domain decomposition approaches for electromagnetic problems that allow the combination of domains discretised by either N\'ed\'elec-type polynomial finite elements or spline-based isogeometric analysis. The first ... More

Instantons and quark zero modes in AdS/QCDSep 16 2009In this paper the quark zero modes creation effect is studied in the context of the AdS/QCD approach. This effect is generated, in presence of instantons, by a new that can be added in the bulk.

Review of the EFT treatment of quarkonium at finite temperatureMar 26 2013Apr 24 2013Heavy quarkonium is one of the most investigated probes of the medium produced in heavy-ion collisions. In the past few years progress has been made in the description of its in-medium dynamics from QCD. Non-relativistic EFTs in particular allow one to ... More

Framed symplectic sheaves on surfacesApr 05 2016Apr 28 2016A framed symplectic sheaf on a smooth projective surface $X$ is a torsion-free sheaf $E$ together with a trivialization on a divisor $D\subseteq X$ and a morphism $\Lambda^{2}E\rightarrow\mathcal{O}_{X}$ satisfying some additional conditions. We construct ... More

A category-theoretic version of the identity type weak factorization systemNov 29 2014Gambino and Garner proved that the syntactic category of a dependent type theory with identity types can be endowed with a weak factorization system structure, called identity type weak factorization system. In this paper we consider an enrichment of ... More

Energy loss at NLO in a high-temperature Quark-Gluon PlasmaJan 25 2016We present an extension of the Arnold-Moore-Yaffe kinetic equations for jet energy loss to NLO in the strong coupling constant. A novel aspect of the NLO analysis is a consistent description of wider-angle bremsstrahlung (semi-collinear emissions), which ... More

Next-to-leading order thermal photon production in a weakly-coupled plasmaApr 02 2014We summarize the recent determination to next-to-leading order of the thermal photon rate at weak coupling. We emphasize how it can be expressed in terms of gauge-invariant condensates on the light cone, which are amenable to novel sum rules and Euclidean ... More

A brief review of the theory of charmonium suppression in heavy ion collisionsNov 28 2013A brief overview of the theory of charmonium suppression in heavy ion collisions is presented. In particular I will concentrate on the effects caused by the hot, deconfined medium and on the effort to treat them using field-theoretical, QCD-based techniques, ... More

A thermodynamical approach to dissipation range turbulenceApr 08 2003A model to explain the statistics of the velocity gradients in the dissipation range of a turbulent flow is presented. The experimentally observed non-gaussian statistics is theoretically predicted by means of a thermodynamical analogy using the maximum ... More

A Multi-agent Based Digital Preservation ModelAug 26 2014Aug 28 2014Master's Degree Thesis: Department of Physics, University of Turin Supervisor: Prof. Marco Maggiora, Department of Physics, University of Turin; email: marco.maggiora@unito.it Co-Supervisor: Prof. Walter Allasia, Innovation Department, EURIX; email: allasia@eurix.it ... More

The thermal dilepton rate at NLO at small and large invariant massOct 02 2015Oct 05 2015We report on a recent next-to-leading order perturbative determination of the dilepton rate from a hot QCD plasma for frequency and momentum of the order of the temperature and for much smaller invariant mass $M\sim gT$. We briefly review the calculation, ... More

Theoretical aspects of photon production in high energy nuclear collisionsJul 31 2014A brief overview of the calculation of photon and dilepton production rates in a deconfined quark-gluon plasma is presented. We review leading order rates as well as recent NLO determinations and non-equilibrium corrections. Furthermore, the difficulties ... More

Heavy quarkonium spectrum and width in a weakly-coupled quark-gluon plasmaAug 30 2011Sep 20 2011We report a recent calculation of the heavy quarkonium energy levels and decay widths in a quark- gluon plasma whose temperature is much smaller than the inverse radius of the bound state, based on a Non-Relativistic Effective Field theory framework for ... More

The Polyakov loop correlator at NNLO and singlet and octet correlatorsOct 19 2010We present the complete next-to-next-to-leading-order calculation of the correlation function of two Polyakov loops for temperatures smaller than the inverse distance between the loops and larger than the Coulomb potential. We discuss the relationship ... More

Effective Field Theories of QCD for Heavy Quarkonia at Finite TemperatureJan 13 2012Quarkonium suppression is one of the most investigated probes of the medium produced in heavy-ion collisions. In this thesis we extend the well-established and successful zero temperature framework of Non-Relativistic (NR) Effective Field Theories (EFTs) ... More

Localization properties of one-dimensional speckle potentials in a boxDec 10 2012Mar 18 2014We investigate the localization properties of the single particle spectrum of a one-dimensional speckle potential in a box. We consider both the repulsive and the attractive cases. The system is controlled by two parameters: the size of the box and a ... More

Holder regularity and chaotic attractorsApr 06 2001Apr 13 2001We demonstrate how the Holder regularity of a given signal is a lower bound for the Grassberger-Procaccia correlation dimension of strange attractors.

Simple linear compactifications of odd orthogonal groupsMar 10 2011Nov 19 2012We classify the simple linear compactifications of SO(2r+1), namely those compactifications with a unique closed orbit which are obtained by taking the closure of the SO(2r+1)xSO(2r+1)-orbit of the identity in a projective space P(End(V)), where V is ... More

On the class of continuous images of non-commutative Valdivia compactaMar 11 2016We investigate the class of continuous images of non-commutative Valdivia compact spaces, in particular its subclass of weakly non-commutative Cor- son countably compact spaces. A key tool is the study of non-commutative Corson countably compact spaces ... More

Comments on the Chiral Symmetry Breaking in Soft Wall Holographic QCDDec 14 2009Dec 23 2009In this paper we describe qualitatively some aspects of the holographic QCD. Inspired by a successfull 4D description, we try to separate the Confinement and the Chiral Symmetry Breaking dynamics. We also discuss the realization of the baryons as skyrmions ... More

Unstable BlowupsFeb 06 2007Nov 12 2007Let (X,L) be a polarised manifold. We show that K-stability and asymptotic Chow stability of the blowup of X along a 0-dimensional cycle are closely related to Chow stability of the cycle itself, for polarizations making the exceptional divisors small. ... More

Universal covers and the GW/Kronecker correspondenceNov 22 2010Nov 28 2011The tropical vertex is an incarnation of mirror symmetry found by Gross, Pandharipande and Siebert. It can be applied to m-Kronecker quivers K(m) (together with a result of Reineke) to compute the Euler characteristics of the moduli spaces of their (framed) ... More

Spherical orbit closures in simple projective spaces and their normalizationsJul 07 2009Oct 19 2010Let G be a simply connected semisimple algebraic group over an algebraically closed field k of characteristic 0 and let V be a rational simple G-module of finite dimension. If G/H \subset P(V) is a spherical orbit and if X is its closure, then we describe ... More

Statistical Hadronization and HolographyDec 14 2009Dec 17 2009In this paper we consider some issues about the statistical model of the hadronization in a holographic approach. We introduce a Rindler like horizon in the bulk and we understand the string breaking as a tunneling event under this horizon. We calculate ... More

QCD condensates in ADS/QCDSep 25 2009This paper focuses on some issues about condensates and renormalization in AdS/QCD models. In particular we consider the consistency of the AdS/QCD approach for scale dependent quantities as the chiral condensate questioned in some recent papers and the ... More

Renormalization Group independence of Cosmological AttractorsNov 15 2016The large class of inflationary models known as $\alpha$- and $\xi$-attractors give identical predictions at tree level (at leading order in inverse power of the number of efolds). Working with the renormalization group improved action, we show that these ... More

Joyce-Song wall-crossing as an asymptotic expansionDec 09 2011Jun 17 2013We conjecture that the Joyce-Song wall-crossing formula for Donaldson-Thomas invariants arises naturally from an asymptotic expansion in the field theoretic work of Gaiotto, Moore and Neitzke. This would also give a new perspective on how the formulae ... More

D0-D6 states counting and GW invariantsDec 15 2009We describe a correspondence between the virtual number of torsion free sheaves locally free in codimension 3 on a Calabi-Yau 3-fold and the Gromov-Witten invariants counting rational curves in a family of orbifold blowups of the weighted projective plane ... More

Recent Advances of Isogeometric Analysis in Computational ElectromagneticsSep 18 2017In this communication the advantages and drawbacks of the isogeometric analysis (IGA) are reviewed in the context of electromagnetic simulations. IGA extends the set of polynomial basis functions, commonly employed by the classical Finite Element Method ... More

Parton energy loss and momentum broadening at NLO in high temperature QCD plasmasFeb 12 2015We present an overview of a perturbative-kinetic approach to jet propagation, energy loss, and momentum broadening in a high temperature quark-gluon plasma. The leading-order kinetic equations describe the interactions between energetic jet-particles ... More

The asymptotic smile of a multiscaling stochastic volatility modelJan 14 2015Oct 05 2016We consider a stochastic volatility model which captures relevant stylized facts of financial series, including the multi-scaling of moments. The volatility evolves according to a generalized Ornstein-Uhlenbeck processes with super-linear mean reversion. ... More

Symmetry breaking for Schrödinger-Poisson-Slater energyJan 21 2016We study the asymptotic behavior of ground state energy for Schr\"odinger-Poisson-Slater energy functional. We show that ground state energy restricted to radially symmetric functions is above the ground state energy when the number of particles is sufficiently ... More

On the theory of quantum quenches in near-critical systemsAug 26 2016Sep 21 2016The theory of quantum quenches in near-critical one-dimensional systems formulated in [J. Phys. A 47 (2014) 402001] yields analytic predictions for the dynamics, unveils a qualitative difference between non-interacting and interacting systems, with undamped ... More

Frobenius type and CV-structures for Donaldson-Thomas theory and a convergence propertyDec 03 2015We rephrase some well-known results in Donaldson-Thomas theory in terms of (formal families of) Frobenius type and CV-structures on a vector bundle in the sense of Hertling. We study these structures in an abstract setting, and prove a convergence result ... More

Extracting Information from Multiplex NetworksFeb 28 2016May 16 2016Multiplex networks are generalized network structures that are able to describe networks in which the same set of nodes are connected by links that have different connotations. Multiplex networks are ubiquitous since they describe social, financial, engineering ... More

Non-stationary Magnetic Microstructures in Stellar Thin Accretion DiscsSep 24 2012Feb 27 2013We examine the morphology of magnetic structures in thin plasma accretion discs, generalizing a stationary ideal MHD model to the time-dependent visco-resistive case. Our analysis deals with small scale perturbations to a central dipole-like magnetic ... More

Sequential visibility-graph motifsDec 01 2015May 02 2016Visibility algorithms transform time series into graphs and encode dynamical information in their topology, paving the way for graph-theoretical time series analysis as well as building a bridge between nonlinear dynamics and network science. In this ... More

Efficient functional ANOVA through wavelet-domain Markov grovesFeb 12 2016Feb 21 2016We introduce a wavelet-domain functional analysis of variance (fANOVA) method based on a Bayesian hierarchical model. The factor effects are modeled through a spike-and-slab mixture at each location-scale combination along with a normal-inverse-Gamma ... More

Critical Exponents of the Random Field Hierarchical ModelSep 28 2013We have studied the one dimensional Dyson hierarchical model in presence of a random field. This is a long range model where the interactions scale with the distance with a power law-like form J(r) ~ r^{-\rho} and we can explore mean field and non-mean ... More

Normality and smoothness of simple linear group compactificationsMar 07 2012Nov 19 2012If G is a complex semisimple algebraic group, we characterize the normality and the smoothness of its simple linear compactifications, namely those equivariant GxG-compactifications which possess a unique closed orbit and which arise in a projective space ... More

Orbits of strongly solvable spherical subgroups on the flag varietyNov 21 2014Apr 07 2016Let G be a connected reductive complex algebraic group and B a Borel subgroup of G. We consider a subgroup H of B acting with finitely many orbits on the flag variety G/B, and we classify the H-orbits in G/B in terms of suitable combinatorial invariants. ... More

Nonlinear Schrödinger equations with strongly singular potentialsMar 19 2009In this paper we look for standing waves for nonlinear Schr\"odinger equations $$ i\frac{\partial \psi}{\partial t}+\Delta \psi - g(|y|) \psi -W^{\prime}(| \psi |)\frac{\psi}{| \psi |}=0 $$ with cylindrically symmetric potentials $g$ vanishing at infinity ... More

Stability and instability results in a model of Fermi accelerationMar 07 2008We consider the static wall approximation to the dynamics of a particle bouncing on a periodically oscillating infinitely heavy plate while subject to a potential force. We assume the case of a potential given by a power of the particle's height and sinusoidal ... More

Orbits of strongly solvable spherical subgroups on the flag varietyNov 21 2014Aug 02 2017Let G be a connected reductive complex algebraic group and B a Borel subgroup of G. We consider a subgroup H of B acting with finitely many orbits on the flag variety G/B, and we classify the H-orbits in G/B in terms of suitable combinatorial invariants. ... More

The asymptotic smile of a multiscaling stochastic volatility modelJan 14 2015Jul 06 2017We consider a stochastic volatility model which captures relevant stylized facts of financial series, including the multi-scaling of moments. The volatility evolves according to a generalized Ornstein-Uhlenbeck processes with super-linear mean reversion. ... More

Torus equivariant K-stabilityFeb 10 2016We prove (using algebro-geometric methods) two results that allow to test the positivity of the Donaldson-Futaki weights of arbitrary polarised varieties via test-configurations which are equivariant with respect to a maximal torus in the automorphism ... More

Equilibrium and nonequilibrium entanglement properties of 2D and 3D Fermi gasesJan 16 2013Mar 01 2013We investigate the entanglement properties of the equilibrium and nonequilibrium quantum dynamics of 2D and 3D Fermi gases, by computing entanglement entropies of extended space regions, which generally show multiplicative logarithmic corrections to the ... More

Il fisico del neutrinoOct 29 2013Nov 11 2014In memory of the famous physicist Bruno Pontecorvo, whereof is just occurred the centenary anniversary of the birth and the twentieth anniversary of the death, this paper traces the scientific and human adventure of the italian scientist, from the pioneering ... More

Robust Financial BubblesFeb 17 2016We study the concept of financial bubble in a market model endowed with a set of probability measures, typically mutually singular to each other. In this setting we introduce the notions of robust bubble and robust fundamental value in a consistent way ... More

Backtesting Lambda Value at RiskFeb 24 2016Jun 12 2016A new risk measure, the lambda value at risk (Lambda VaR), has been recently proposed from a theoretical point of view as a generalization of the value at risk (VaR). The Lambda VaR appears attractive for its potential ability to solve several problems ... More

Modelling and interpreting spectral energy distributions of galaxies with BEAGLEMar 09 2016Oct 05 2016We present a new-generation tool to model and interpret spectral energy distributions (SEDs) of galaxies, which incorporates in a consistent way the production of radiation and its transfer through the interstellar and intergalactic media. This flexible ... More

Analysis of distributional variation through multi-scale Beta-Binomial modelingApr 05 2016Many statistical analyses involve the comparison of multiple data sets collected under different conditions in order to identify the difference in the underlying distributions. A common challenge in multi-sample comparison is the presence of various confounders, ... More

Multi-resolution two-sample comparison through the divide-merge Markov treeApr 14 2014May 29 2014We introduce a probabilistic framework for two-sample comparison based on a nonparametric process taking the form of a Markov model that transitions between a "divide" and a "merge" state on a multi-resolution partition tree of the sample space. Multi-scale ... More

Phase separation and interface structure in two dimensions from field theoryJun 21 2012Oct 30 2012We study phase separation in two dimensions in the scaling limit below criticality. The general form of the magnetization profile as the volume goes to infinity is determined exactly within the field theoretical framework which explicitly takes into account ... More

Potts q-color field theory and scaling random cluster modelApr 21 2011Jul 01 2011We study structural properties of the q-color Potts field theory which, for real values of q, describes the scaling limit of the random cluster model. We show that the number of independent n-point Potts spin correlators coincides with that of independent ... More

On three-point connectivity in two-dimensional percolationSep 07 2010We argue the exact universal result for the three-point connectivity of critical percolation in two dimensions. Predictions for Potts clusters and for the scaling limit below p_c are also given.

Stable standing waves for a class of nonlinear Schroedinger-Poisson equationsFeb 09 2010Mar 25 2010We prove the existence of orbitally stable standing waves with prescribed $L^2$-norm for the following Schr\"odinger-Poisson type equation \label{intro} %{%{ll} i\psi_{t}+ \Delta \psi - (|x|^{-1}*|\psi|^{2}) \psi+|\psi|^{p-2}\psi=0 \text{in} \R^{3}, %-\Delta\phi= ... More

Wavelet Cross-Correlation Analysis of Turbulent Mixing from Large-Eddy-SimulationsMar 14 2000The complex interactions existing between turbulence and mixing in a bluff-body stabilised flame configuration is investigated by means of a wavelet cross-correlation analysis on Large Eddy Simulations. The combined approach allows to better point out ... More

Regular functions on spherical nilpotent orbits in complex symmetric pairs: classical Hermitian casesDec 05 2016Given a classical semisimple complex algebraic group G and a symmetric pair (G,K) of Hermitian type, we study the closures of the spherical nilpotent K-orbits in the isotropy representation of K. We show that all such orbit closures are normal and describe ... More

The Bruhat order on Hermitian symmetric varieties and on abelian nilradicalsAug 18 2017Jul 12 2018Let $G$ be a simple algebraic group and $P$ a parabolic subgroup of $G$ with abelian unipotent radical $P^u$, and let $B$ be a Borel subgroup of $G$ contained in P. Let $\mathfrak{p}^u$ be the Lie algebra of $P^u$ and let $L$ be a Levi factor of $P$, ... More

Spectral triples on the Jiang-Su algebraSep 24 2017Feb 01 2018We construct spectral triples on a class of particular inductive limits of matrix-valued function algebras. In the special case of the Jiang-Su algebra we employ a particular $AF$-embedding.

DepecheMood: a Lexicon for Emotion Analysis from Crowd-Annotated NewsMay 07 2014While many lexica annotated with words polarity are available for sentiment analysis, very few tackle the harder task of emotion analysis and are usually quite limited in coverage. In this paper, we present a novel approach for extracting - in a totally ... More

UV (in)sensitivity of Higgs inflationFeb 23 2016Apr 27 2016The predictions of Standard Model Higgs inflation are in excellent agreement with the Planck data, without the need for new fields. However, consistency of the theory requires the presence of (unknown) threshold corrections. These modify the running of ... More

Crossing probability and number of crossing clusters in off-critical percolationOct 28 2011Dec 19 2011We consider two-dimensional percolation in the scaling limit close to criticality and use integrable field theory to obtain universal predictions for the probability that at least one cluster crosses between opposite sides of a rectangle of sides much ... More

Universal properties of Ising clusters and droplets near criticalityJun 11 2010Clusters and droplets of positive spins in the two-dimensional Ising model percolate at the Curie temperature in absence of external field. The percolative exponents coincide with the magnetic ones for droplets but not for clusters. We use integrable ... More

On dipolar quantum gases in the unstable regimeOct 17 2014Mar 25 2016We study the nonlinear Schr\"odinger equation arising in dipolar Bose-Einstein condensate in the unstable regime. Two cases are studied: the first when the system is free, the second when gradually a trapping potential is added. In both cases we first ... More

On translation invariant constrained minimization problems with application to Schrödinger-Poisson equationJul 23 2010Nov 19 2010In this paper we study the existence of minimizers for a class of constrained minimization problems that are invariant under translations. We call $$I_{\rho^{2}}:=\inf_{B_{\rho}}I(u) \ $$ where $B_{\rho}=\{u\in H^{m}(\R^{N}):\|u\|_{2}=\rho\},$ and $I(u)=1/2\|u\|^{2}_{D^{m,2}}+T(u)$, ... More

General smile asymptotics with bounded maturityNov 06 2014Jul 07 2016We provide explicit conditions on the distribution of risk-neutral log-returns which yield sharp asymptotic estimates on the implied volatility smile. We allow for a variety of asymptotic regimes, including both small maturity (with arbitrary strike) ... More

Comparison between different methods of estimating of the relaxation times in the FPU modelApr 29 2015After a brief review of the Fermi-Pasta-Ulam (FPU) conservative system of N nonlinearly coupled oscillators, this paper addresses two problems: first, comparing two indicators for the equipartition, showing that the results are essentially identical; ... More

Braid group actions on coideal subalgebras of quantized enveloping algebrasFeb 21 2011We construct braid group actions on coideal subalgebras of quantized enveloping algebras which appear in the theory of quantum symmetric pairs. In particular, we construct an action of the semidirect product of Z^n and the classical braid group in n strands ... More

Sequential motif profile of natural visibility graphsMay 09 2016The concept of sequential visibility graph motifs -subgraphs appearing with characteristic frequencies in the visibility graphs associated to time series- has been advanced recently along with a theoretical framework to compute analytically the motif ... More

Relative K-stability of extremal metricsDec 21 2009We show that if a polarised manifold admits an extremal metric then it is K-polystable relative to a maximal torus of automorphisms.

Max-Min characterization of the mountain pass energy level for a class of variational problemsSep 01 2009We provide a max-min characterization of the mountain pass energy level for a family of variational problems. As a consequence we deduce the mountain pass structure of solutions to suitable PDEs, whose existence follows from classical minimization argument. ... More

Local logarithmic correlators as limits of Coulomb gas integralsNov 08 2013We will describe how logarithmic singularities arise as limits of Coulomb Gas integrals. Our approach will combine analytic properties of the time-like Liouville structure constants, together with the recursive formula of the Virasoro conformal blocks. ... More

Dynamics of some piecewise smooth Fermi-Ulam ModelsDec 11 2011We find a normal form which describes the high energy dynamics of a class of piecewise smooth Fermi-Ulam ping pong models; depending on the value of a single real parameter, the dynamics can be either hyperbolic or elliptic. In the first case we prove ... More

Potts models on hierarchical lattices and Renormalization Group dynamicsAug 04 2007Aug 03 2008We prove that the generator of the renormalization group of Potts models on hierarchical lattices can be represented by a rational map acting on a finite-dimensional product of complex projective spaces. In this framework we can also consider models with ... More

Fast-slow partially hyperbolic systems: beyond averaging. Part I (Limit Theorems)Aug 23 2014Sep 11 2014We prove several limit theorems for a simple class of partially hyperbolic fast-slow systems. We start with some well know results on averaging, then we give a substantial refinement of known large (and moderate) deviation results and conclude with a ... More

TBA type equations and tropical curvesJun 17 2013We revisit the wall-crossing behaviour of solutions to the Thermodynamic Bethe Ansatz type equations arising in a class of three-dimensional field theories, expressed as sums of "instanton corrections". We explain how to attach to an instanton correction ... More

The martingale approach after Varadhan and DolgopyatFeb 01 2014Sep 12 2014We present, in the simplest possible form, the so called martingale problem strategy to establish limit theorems. The presentation is specially adapted to problems arising in partially hyperbolic dynamical systems. We will discuss a simple partially hyperbolic ... More

On the interplay between hypergeometric series, Fourier-Legendre expansions and Euler sumsJun 21 2018In this work we continue the investigation about the interplay between hypergeometric functions and Fourier-Legendre ($\textrm{FL}$) series expansions. In the section "Hypergeometric series related to $\pi,\pi^2$ and the lemniscate constant", through ... More

Limit Theorems for Fast-slow partially hyperbolic systemsAug 23 2014Nov 03 2017We prove several limit theorems for a simple class of partially hyperbolic fast-slow systems. We start with some well know results on averaging, then we give a substantial refinement of known large (and moderate) deviation results and conclude with a ... More

On the Hausdorff dimension of Newhouse phenomenaApr 08 2014We show that at the vicinity of a generic dissipative homoclinic unfolding of a surface diffeomorphism, the Hausdorff dimension of the set of parameters for which the diffeomorphism admits infinitely many periodic sinks is at least 1/2.

On the Existence of Martingale Measures in Jump Diffusion Market ModelsNov 26 2015In the context of jump-diffusion market models we construct examples that satisfy the weaker no-arbitrage condition of NA1 (NUPBR), but not NFLVR. We show that in these examples the only candidate for the density process of an equivalent local martingale ... More

Block-Göttsche invariants from wall-crossingDec 20 2012Nov 29 2015We show how some of the refined tropical counts of Block and G\"ottsche emerge from the wall-crossing formalism. This leads naturally to a definition of a class of putative q-deformed Gromov-Witten invariants. We prove that this coincides with another ... More

Exact correlations in the Lieb-Liniger model and detailed balance out-of-equilibriumNov 01 2016Nov 07 2016We study the density-density correlation function of the 1D Lieb-Liniger model and obtain an exact expression for the small momentum limit of the static correlator in the thermodynamic limit. We achieve this by summing exactly over the relevant form factors ... More

Low Mass Thermal Dilepton Production at NLO in a Weakly Coupled Quark-Gluon PlasmaOct 15 2014Dec 03 2014We present a computation, within weakly-coupled thermal QCD, of the production rate of low invariant mass ($M^2 \sim g^2 T^2$) dileptons, at next-to-leading order (NLO) in the coupling (which is $O(g^3 e^2 T^2)$). This involves extending the NLO calculation ... More

Statistical properties of mostly contracting fast-slow partially hyperbolic systemsAug 23 2014Oct 15 2015We consider a class of $\mathcal C^{4}$ partially hyperbolic systems on $\mathbb T^2$ described by maps $F_\varepsilon(x,\theta)=(f(x,\theta),\theta+\varepsilon\omega(x,\theta))$ where $f(\cdot,\theta)$ are expanding maps of the circle. For sufficiently ... More

Exact correlations in the Lieb-Liniger model and detailed balance out-of-equilibriumNov 01 2016We study the density-density correlation function of the 1D Lieb-Liniger model and obtain an exact expression for the small momentum limit of the static correlator in the thermodynamic limit. We achieve this by summing exactly over the relevant form factors ... More

Density form factors of the 1D Bose gas for finite entropy statesNov 17 2014Mar 18 2015We consider the Lieb-Liniger model for a gas of bosonic $\delta-$interacting particles. Using Algebraic Bethe Ansatz results we compute the thermodynamic limit of the form factors of the density operator between finite entropy eigenstates such as finite ... More

Exploring Image Virality in Google PlusSep 16 2013Reactions to posts in an online social network show different dynamics depending on several textual features of the corresponding content. Do similar dynamics exist when images are posted? Exploiting a novel dataset of posts, gathered from the most popular ... More

An Enhanced Features Extractor for a Portfolio of Constraint SolversAug 01 2013Apr 02 2014Recent research has shown that a single arbitrarily efficient solver can be significantly outperformed by a portfolio of possibly slower on-average solvers. The solver selection is usually done by means of (un)supervised learning techniques which exploit ... More

Predicting epidemic evolution on contact networks from partial observationsAug 23 2016The massive employment of computational models in network epidemiology calls for the development of improved inference methods for epidemic forecast. For simple compartment models, such as the Susceptible-Infected-Recovered model, Belief Propagation was ... More

Column-Oriented Datalog Materialization for Large Knowledge Graphs (Extended Technical Report)Nov 28 2015Feb 11 2016The evaluation of Datalog rules over large Knowledge Graphs (KGs) is essential for many applications. In this paper, we present a new method of materializing Datalog inferences, which combines a column-based memory layout with novel optimization methods ... More

Ground states for semi-relativistic Schrödinger-Poisson-Slater energiesMar 14 2011Apr 08 2014We prove the existence of ground states for the semi-relativistic Schr\"odinger-Poisson-Slater energy $$I^{\alpha,\beta}(\rho)=\inf_{\substack{u\in H^\frac 12(\R^3) \int_{\R^3}|u|^2 dx=\rho}} \frac{1}{2}\|u\|^2_{H^\frac 12(\R^3)} +\alpha\int\int_{\R^{3}\times\R^{3}} ... More

Nonperturbative Instability of AdS_5 x S^5/Z_kSep 26 2007Oct 26 2007We study the AdS/CFT correspondence with boundary conditions AdS_5 x S^5/Z_k, where the Z_k acts freely but breaks all supersymmetry. While there are closed string tachyons at small 't Hooft coupling, there are no tachyons at large coupling. Nevertheless, ... More

Regular functions on spherical nilpotent orbits in complex symmetric pairs: classical non-Hermitian casesFeb 23 2016Given a classical semisimple complex algebraic group G and a symmetric pair (G, K) of non-Hermitian type, we study the closures of the spherical nilpotent K-orbits in the isotropy representation of K. For all such orbit closures, we study the normality ... More

Projective normality of model varieties and related resultsApr 23 2013Dec 31 2015We prove that the multiplication of sections of globally generated line bundles on a model wonderful variety M of simply connected type is always surjective. This follows by a general argument which works for every wonderful variety and reduces the study ... More