Results for "Alessandro Palmieri"

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Fujita versus Strauss - a never ending storyOct 25 2017In this paper, we obtain a blow-up result for solutions to a semi-linear wave equation with scale-invariant dissipation and mass and power non-linearity, in the case in which the model has a "wave like" behavior. In order to achieve this goal, we perform ... More
Nonexistence of global solutions for a weakly coupled system of semilinear damped wave equations of derivative type in the scattering caseDec 27 2018In this paper we consider the blow-up for solutions to a weakly coupled system of semilinear damped wave equations of derivative type in the scattering case. After introducing suitable functionals proposed by Lai-Takamura for the corresponding single ... More
Integral representation formulae for the solution of a wave equation with time-dependent damping and mass in the scale-invariant caseMay 07 2019This paper is devoted to derive integral representation formulae for the solution of an inhomogeneous linear wave equation with time-dependent damping and mass terms, that are scale-invariant with respect to the so-called hyperbolic scaling. Yagdjian's ... More
A global existence result for a semilinear wave equation with scale-invariant damping and mass in even space dimensionApr 11 2018In the present article a semilinear wave equation with scale-invariant damping and mass is considered. The global (in time) existence of radial symmetric solutions in even spatial dimension $n$ is proved using weighted $L^\infty-L^\infty$ estimates, under ... More
A note on a conjecture for the critical curve of a weakly coupled system of semilinear wave equations with scale-invariant lower order termsDec 17 2018In this note two blow-up results are proved for a weakly coupled system of semilinear wave equations with distinct scale-invariant lower order terms both in the subcritical case and in the critical case, when the damping and the mass terms make both equations ... More
Global existence of solutions for semi-linear wave equation with scale-invariant damping and mass in exponentially weighted spacesAug 02 2017In this paper we consider the following Cauchy problem for the semi-linear wave equation with scale-invariant dissipation and mass and power non-linearity: \begin{align}\label{CP abstract} \begin{cases} u_{tt}-\Delta u+\dfrac{\mu_1}{1+t} u_t+\dfrac{\mu_2^2}{(1+t)^2}u=|u|^p, ... More
Weakly coupled system of semilinear wave equations with distinct scale-invariant terms in the linear partSep 26 2018In this work we determine the critical exponent for a weakly coupled system of semilinear wave equations with distinct scale-invariant lower order terms, when these terms make both equations in some sense parabolic-like. For the blow-up result the test ... More
Nonexistence of global solutions for a weakly coupled system of semilinear damped wave equations in the scattering case with mixed nonlinear termsJan 13 2019In this paper we consider the blow-up of solutions to a weakly coupled system of semilinear damped wave equations in the scattering case with nonlinearities of mixed type, namely, in one equation a power nonlinearity and in the other a semilinear term ... More
Lifespan estimates for local in time solutions to the semilinear heat equation on the Heisenberg groupMay 14 2019In this paper we consider the semilinear Cauchy problem for the heat equation with power nonlinearity in the Heisenberg group $\mathbf{H}_n$. The heat operator is given in this case by $\partial_t-\Delta_H$, where $\Delta_H$ is the so-called sub-Laplacian ... More
Lifespan of semilinear wave equation with scale invariant dissipation and mass and sub-Strauss power nonlinearityMay 17 2018In this paper, we study the blow-up of solutions for semilinear wave equations with scale-invariant dissipation and mass in the case in which the model is somehow 'wave-like'. A Strauss type critical exponent is determined as the upper bound for the exponent ... More
Blow-up for a weakly coupled system of semilinear damped wave equations in the scattering case with power nonlinearitiesDec 25 2018In this work we study the blow-up of solutions of a weakly coupled system of damped semilinear wave equations in the scattering case with power nonlinearities. We apply an iteration method to study both the subcritical case and the critical case. In the ... More
Multiple solutions for p-Laplacian type problems with asymptotically p-linear terms via a cohomological index theoryOct 02 2013The aim of this paper is investigating the existence of weak solutions of the quasilinear elliptic model problem \[ \left\{\begin{array}{lr} - \divg (A(x,u)\, |\nabla u|^{p-2}\, \nabla u) + \dfrac1p\, A_t(x,u)\, |\nabla u|^p\ =\ f(x,u) & \hbox{in $\Omega$,}\\ ... More
Nero's "solar" kingship and the architecture of Domus AureaDec 29 2013Dec 31 2013The Domus Aurea, Nero's last "palace" constructed in the very heart of ancient Rome, is a true masterpiece of Roman architecture. We explore here symbolic aspects of the emperor's project, analysing the archaeoastronomy of the best preserved part of the ... More
On a ternary Diophantine problem with mixed powers of primesJun 01 2012Jul 30 2012Let $1 < k < 33 / 29$. We prove that if $\lambda_1$, $\lambda_2$ and $\lambda_3$ are non-zero real numbers, not all of the same sign and that $\lambda_1 / \lambda_2$ is irrational and $\varpi$ is any real number, then for any $\eps > 0$ the inequality ... More
A Diophantine problem with a prime and three squares of primesJun 01 2012We prove that if $\lambda_1$, $\lambda_2$, $\lambda_3$ and $\lambda_4$ are non-zero real numbers, not all of the same sign, $\lambda_1 / \lambda_2$ is irrational, and $\varpi$ is any real number then, for any $\eps > 0$ the inequality $ \bigl|\lambda_1 ... More
Gross-Pitaevskii non-linear dynamics for pseudo-spinor condensatesApr 01 2017Oct 18 2017We derive the equations for the non-linear effective dynamics of a so called pseudo-spinor Bose-Einstein condensate, which emerges from the linear many-body Schr\"odinger equation at the leading order in the number of particles. The considered system ... More
A Cesàro Average of Hardy-Littlewood numbersJun 01 2012Let $\Lambda$ be the von Mangoldt function and (r_{\textit{HL}}(n) = \sum_{m_1 + m_2^2 = n} \Lambda(m_1),) be the counting function for the Hardy-Littlewood numbers. Let $N$ be a sufficiently large integer. We prove that \sum_{n \le N} r_{\textit{HL}}(n) ... More
A Flexible Framework for Accurate Simulation of Cloud In-Memory Data StoresNov 28 2014In-memory (transactional) data stores are recognized as a first-class data management technology for cloud platforms, thanks to their ability to match the elasticity requirements imposed by the pay-as-you-go cost model. On the other hand, defining the ... More
System and source identification from operational vehicle responses: A novel modal model accounting for the track-vehicle interactionJan 07 2017Operational Modal Analysis (OMA) is a powerful tool, widely used in the fields of structural identification and health monitoring, and certainly eligible for identifying the real in-operation behaviour of vehicle systems. Several attempts can be found ... More
Sums of many primesJan 18 2011Assuming that the Generalized Riemann Hypothesis (GRH) holds, we prove an explicit formula for the number of representations of an integer as a sum of $k\geq 5$ primes. Our error terms in such a formula improve by some logarithmic factors an analogous ... More
A Diophantine problem with prime variablesJun 01 2012We study the distribution of the values of the form $\lambda_1 p_1 + \lambda_2 p_2 + \lambda_3 p_3^k$, where $\lambda_1$, $\lambda_2$ and $\lambda_3$ are non-zero real number not all of the same sign, with $\lambda_1 / \lambda_2$ irrational, and $p_1$, ... More
A Credal Extension of Independent Choice LogicJun 21 2018We propose an extension of Poole's independent choice logic based on a relaxation of the underlying independence assumptions. A credal semantics involving multiple joint probability mass functions over the possible worlds is adopted. This represents a ... More
Short intervals asymptotic formulae for binary problems with prime powers, IIOct 26 2018We improve some results about the asymptotic formulae in short intervals for the average number of representations of integers of the forms $n=p_{1}^{\ell_1}+p_{2}^{\ell_2}$ and $n=p^{\ell_1} + m^{\ell_2}$, where $\ell_1, \ell_2\ge 2$ are fixed integers, ... More
Mean-field quantum dynamics for a mixture of Bose-Einstein condensatesMar 08 2016Sep 12 2016We study the effective time evolution of a large quantum system consisting of a mixture of different species of identical bosons in interaction. If the system is initially prepared so as to exhibit condensation in each component, we prove that condensation ... More
Cesàro average in short intervals for Goldbach numbersJun 02 2016We prove that a suitable explicit formula for the Cesaro-averaged number of representations of an integer as a sum of two primes holds in short intervals.
Short intervals asymptotic formulae for binary problems with prime powersJun 14 2018Jun 21 2018We prove results about the asymptotic formulae in short intervals for the average number of representations of integers of the forms $n=p_{1}^{\ell_1}+p_{2}^{\ell_2}$, with $\ell_1, \ell_2\in\{2,3\}$, $\ell_1+\ell_2\le 5$ are fixed integers, and $n=p^{\ell_1} ... More
Effective non-linear spinor dynamics in a spin-1 Bose-Einstein condensateMar 14 2018Sep 03 2018We derive from first principles the experimentally observed effective dynamics of a spinor Bose gas initially prepared as a Bose-Einstein condensate and then left free to expand ballistically. In spinor condensates, which represent one of the recent frontiers ... More
A Cesàro Average of Goldbach numbersJun 01 2012Let $\Lambda$ be the von Mangoldt function and (r_G(n) = \sum_{m_1 + m_2 = n} \Lambda(m_1) \Lambda(m_2)) be the counting function for the Goldbach numbers. Let $N \geq 2$ be an integer. We prove that &\sum_{n \le N} r_G(n) \frac{(1 - n/N)^k}{\Gamma(k ... More
Short intervals asymptotic formulae for binary problems with primes and powers, II: density $1$Apr 18 2015Nov 28 2015We prove that suitable asymptotic formulae in short intervals hold for the problems of representing an integer as a sum of a prime square and a square, or a prime square. Such results are obtained both assuming the Riemann Hypothesis and in the unconditional ... More
Short intervals asymptotic formulae for binary problems with primes and powers, I: density $3/2$Apr 09 2015Nov 28 2015We prove that suitable asymptotic formulae in short intervals hold for the problems of representing an integer as a sum of a prime and a square, or a prime square. Such results are obtained both assuming the Riemann Hypothesis and in the unconditional ... More
On the constant in the Mertens product for arithmetic progressions. I. IdentitiesJun 19 2007Sep 26 2008The aim of the paper is the proof of new identities for the constant in the Mertens product for arithmetic progressions. We deal with the problem of the numerical computation of these constants in another paper.
The number of Goldbach representations of an integerNov 14 2010We prove the following result: Let $N \geq 2$ and assume the Riemann Hypothesis (RH) holds. Then \[ \sum_{n=1}^{N} R(n) =\frac{N^{2}}{2} -2 \sum_{\rho} \frac{N^{\rho + 1}}{\rho (\rho + 1)} + O(N \log^{3}N), \] where $\rho=1/2+i\gamma$ runs over the non-trivial ... More
Explicit relations between primes in short intervals and exponential sums over primesDec 22 2012Dec 29 2012Under the assumption of the Riemann Hypothesis (RH), we prove explicit quantitative relations between hypothetical error terms in the asymptotic formulae for truncated mean-square average of exponential sums over primes and in the mean-square of primes ... More
A behavioural approach to obstacle avoidance for mobile manipulators based on distributed sensingFeb 09 2015A reactive obstacle avoidance method for mobile manipulators is presented. The objectives of the developed algorithm are twofold. The first one is to find a trajectory in the configuration space of a mobile manipulator so as to follow a given trajectory ... More
Automorphisms of order three on numerical Godeaux surfacesOct 26 2007We prove that a numerical Godeaux surface cannot have an automorphism of order three.
The discriminant criterion and automorphism groups of quantized algebrasFeb 26 2014We compute the automorphism groups of some quantized algebras, including tensor products of quantum Weyl algebras and some skew polynomial rings.
SSS: Scalable Key-Value Store with External Consistent and Abort-free Read-only TransactionsJan 11 2019We present SSS, a scalable transactional key-value store deploying a novel distributed concurrency control that provides external consistency for all transactions, never aborts read-only transactions due to concurrency, all without specialized hardware. ... More
Swarm robotics in wireless distributed protocol design for coordinating robots involved in cooperative tasksApr 22 2018The mine detection in an unexplored area is an optimization problem where multiple mines, randomly distributed throughout an area, need to be discovered and disarmed in a minimum amount of time. We propose a strategy to explore an unknown area, using ... More
X-ray Resonant Magnetic Scattering : Polarisation Dependence in the non-spherical caseJun 06 2006Jul 24 2006We develop a simple tensorial contraction method to obtain analytical formula for X-ray resonant magnetic scattering. We apply the method considering first electric dipole-dipole and electric quadrupole-quadrupole scattering in the isolated atom approximation ... More
Using Dempster-Shafer Theory in Knowledge RepresentationMar 27 2013In this paper, we suggest marrying Dempster-Shafer (DS) theory with Knowledge Representation (KR). Born out of this marriage is the definition of "Dempster-Shafer Belief Bases", abstract data types representing uncertain knowledge that use DS theory for ... More
Sommerfeld corrections to type-II and III leptogenesisJun 10 2008Oct 09 2008We study thermal leptogenesis from decays of the electroweak triplets that mediate neutrino masses in type-II and type-III see-saw. We find that Sommerfeld corrections reduce the baryon asymmetry by ~30%, and that successful leptogenesis needs triplets ... More
Oscillations of three neutrinos with all Delta m^2 approx 10^{-3} eV^2Apr 06 1999Apr 27 1999Oscillations of three neutrinos with all squared mass splittings around 10^{-3} eV^2 are not firmly excluded by solar neutrino experiments. We carefully verify that they are also perfectly compatible with atmospheric neutrino experiments: due to accidental ... More
Baryogenesis via leptogenesisAug 31 2006We discuss how leptogenesis can explain the observed baryon asymmetry and summarize attempts of testing leptogenesis. We first perform estimates and discuss the main physics, and later outline the techniques that allow to perform precise computations. ... More
A primer on Answer Set ProgrammingAug 23 2005A introduction to the syntax and Semantics of Answer Set Programming intended as an handout to [under]graduate students taking Artificial Intlligence or Logic Programming classes.
Epigenetic Tracking: Implementation DetailsJan 18 2010"Epigenetic Tracking" is the name of a model of cellular development that, coupled with an evolutionary technique, becomes an evo-devo (or "artificial embryology", or "computational development") method to generate 2d or 3d sets of artificial cells arbitrarily ... More
Epigenetic Tracking: Towards a Project for an Artificial BiologyApr 29 2009This paper deals with a model of cellular growth called "Epigenetic Tracking", whose key features are: i) distinction bewteen "normal" and "driver" cells; ii) presence in driver cells of an epigenetic memory, that holds the position of the cell in the ... More
Contracting elements and random walksDec 12 2011Oct 31 2013We define a new notion of contracting element of a group and we show that contracting elements coincide with hyperbolic elements in relatively hyperbolic groups, pseudo-Anosovs in mapping class groups, rank one isometries in groups acting properly on ... More
Exponential triplesJul 18 2011Using ultrafilter techniques we show that in any partition of $\mathbb{N}$ into 2 cells there is one cell containing infinitely many exponential triples, i.e. triples of the kind $a,b,a^b$ (with $a,b>1$). Also, we will show that any multiplicative $IP^*$ ... More
Review: A Coherent and Comprehensive Model of the Evolution of the Outer Solar SystemOct 29 2010Since the discovery of the first extra-solar planets, we are confronted with the puzzling diversity of planetary systems. Processes like planet radial migration in gas-disks and planetary orbital instabilities, often invoked to explain the exotic orbits ... More
Origin and Dynamical Evolution of Comets and their ReservoirsDec 09 2005This text was originally written to accompany a series of lectures that I gave at the `35th Saas-Fee advanced course' in Switzerland and at the Institute for Astronomy of the University of Hawaii. It reviews my current understanding of the dynamics of ... More
The Polarized Nucleon in Quark ModelsOct 06 1998A brief overview of various problems related to the description of a polarized proton in quark models is presented. Structure functions are discussed both for longitudinal and transverse polarization. A recently introduced quantity, relevant in the study ... More
The ground state construction of the two-dimensional Hubbard model on the honeycomb latticeFeb 18 2011In these lectures I consider the half-filled two-dimensional (2D) Hubbard model on the honeycomb lattice and I review the rigorous construction of its ground state properties by making use of constructive fermionic Renormalization Group methods.
Cluster variation method and disorder varieties of two-dimensional Ising-like modelsSep 24 1999Jun 06 2000I show that the cluster variation method, long used as a powerful hierarchy of approximations for discrete (Ising-like) two-dimensional lattice models, yields exact results on the disorder varieties which appear when competitive interactions are put into ... More
The half-filled Hubbard model in the pair approximation of the Cluster Variation MethodNov 18 1992Nov 20 1992The half filled Hubbard model is studied in the pair approximation of the Cluster Variation Method. The use of the $SO(4)$ symmetry of the model makes possible to give a complete analytical characterization of the ground state, by means of explicit expressions ... More
Transverse-momentum dependent functions in semi-inclusive DISDec 15 2006The cross section for semi-inclusive deep inelastic scattering can be decomposed in terms of 18 structure functions. At low transverse momentum of the detected hadron, the structure functions can be expressed in terms of transverse-momentum-dependent ... More
The Hawking signal in density-density correlations in BECsFeb 11 2011We outline the derivation of the Hawking quanta-partner signal in correlations, and highlight the specific application to detect it in density-density correlations in BECs.
Entropy of gravitating systems: scaling laws versus radial profilesNov 20 2006Apr 17 2007Through the consideration of spherically symmetric gravitating systems consisting of perfect fluids with linear equation of state constrained to be in a finite volume, an account is given of the properties of entropy at conditions in which it is no longer ... More
Entropy bounds and field equationsApr 30 2014Aug 13 2015For general metric theories of gravity, we compare the approach that describes-derives the field equations of gravity as a thermodynamic identity with the one which looks at them from entropy bounds. The comparison is made through the consideration of ... More
Effective one body Hamiltonian of two spinning black-holes with next-to-next-to-leading order spin-orbit couplingJun 21 2011Sep 05 2013Building on the recently computed next-to-next-to-leading order (NNLO) post-Newtonian (PN) spin-orbit Hamiltonian for spinning binaries \cite{Hartung:2011te} we extend the effective-one-body (EOB) description of the dynamics of two spinning black-holes ... More
Cosmological constraints from Microwave Background Anisotropy and PolarizationNov 25 2003The recent high-quality measurements of the Cosmic Microwave Background anisotropies have presented cosmologists with the possibility of studying the large scale properties of our universe with unprecedented precision. Here I review the current status ... More
CMB and Cosmological Parameters: Current Status and ProspectsApr 01 2002The last years have been an exciting period for the field of the Cosmic Microwave Background (CMB) research. With recent CMB balloon-borne and ground-based experiments we are entering a new era of 'precision' cosmology that enables us to use the CMB anisotropy ... More
An Improved Node Ranking for Label Propagation and Modularity based ClusteringSep 28 2014In this paper I'll speak about non-spectral clustering techniques and see how a node ordering based on centrality measures can improve the quality of communities detected. I'll also discuss an improvement to existing techniques, which further improves ... More
An artificial neural network to find correlation patterns among an arbitrary number of variablesJun 21 2016Methods to find correlation among variables are of interest to many disciplines, including statistics, machine learning, (big) data mining and neurosciences. Parameters that measure correlation between two variables are of limited utility when used with ... More
Difference of powers of consecutive primes which are perfect squaresApr 18 2016We investigate the consecutive primes $p$ and $q$ ($p > q$) for which there exists a pair of natural numbers $(x,y)$ such that $p^x-q^y$ is a perfect square and make some conjectures.
Lectures on Classical IntegrabilityJun 09 2016Jul 27 2016We review some essential aspects of classically integrable systems. The detailed outline of the lectures consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, ... More
Second-Order Functions and Theorems in ACL2Sep 21 2015SOFT ('Second-Order Functions and Theorems') is a tool to mimic second-order functions and theorems in the first-order logic of ACL2. Second-order functions are mimicked by first-order functions that reference explicitly designated uninterpreted functions ... More
Spacetime atoms and extrinsic curvature of equi-geodesic surfacesNov 27 2015May 20 2016A recently-introduced function $\rho$ of spacetime event $P$ expressing spacetime as made of 'spacetime atoms' of quantum origin is considered. Using its defining relation, we provide an exact expression for $\rho$ involving the van Vleck biscalar, and ... More
A theoretical model of soma-to-germline transmission of transposable elements to build new gene regulatory sequencesSep 21 2015Nov 03 2015Transposable elements are DNA sequences that can move around to different positions in the genome. During this process, they can cause mutations, and lead to an increase in genome size. Despite representing a large genomic fraction, transposable elements ... More
Quadripolar Relational Model: a framework for the description of borderline and narcissistic personality disordersDec 18 2015Oct 25 2016Borderline personality disorder and narcissistic personality disorder are important nosographic entities and have been subject of intensive investigations. The currently prevailing psychodynamic theory for mental disorders is based on the repertoire of ... More
Matrix Algebras in Non-Hermitian Quantum MechanicsDec 04 2010Feb 04 2011In principle, non-Hermitian quantum equations of motion can be formulated using as a starting point either the Heisenberg's or the Schr\"odinger's picture of quantum dynamics. Here it is shown in both cases how to map the algebra of commutators, defining ... More
Embedding quantum systems with a non-conserved probability in classical environmentsFeb 21 2015Jun 06 2015Quantum systems with a non-conserved probability can be described by means of non-Hermitian Hamiltonians and non-unitary dynamics. In this paper, the case in which the degrees of freedom can be partitioned in two subsets with light and heavy masses is ... More
Deterministic constant-temperature dynamics for dissipative quantum systemsJan 31 2007Mar 08 2007A novel method is introduced in order to treat the dissipative dynamics of quantum systems interacting with a bath of classical degrees of freedom. The method is based upon an extension of the Nos\`e-Hoover chain (constant temperature) dynamics to quantum-classical ... More
Hysteresis properties at zero temperature in the Dipolar-Random Field Ising ModelJul 06 1999We present a modified two-dimensional random field Ising model, where a dipolar interaction term is added to the classic random field Hamiltonian. In a similar model it was already verified that the system state can exhibit domains in the form of stripe ... More
Status and Perspectives of Neutrino PhysicsNov 02 2004I will first give a brief but comprehensive review of the status of our knowledge in neutrino physics. With reference to a not too far future I will then discuss the perspectives that appear to me to be most important and promising.
A note on the computation of the Euler-Kronecker constants for cyclotomic fieldsMar 13 2019The goal of this note is to introduce an alternative method to compute the Euler-Kronecker constants for cyclotomic fields and to compare it with other two different ways of computing the same quantity. The new algorithm requires the values of the generalised ... More
One approach to the digital visualization of hedgehogs in holomorphic dynamicsSep 22 2006Sep 24 2006In the field of holomorphic dynamics in one complex variable, hedgehog is the local invariant set arising about a Cremer point and endowed with a very complicate shape as well as relating to very weak numerical conditions. We give a solution to the open ... More
Rational parametrizations of moduli spaces of curvesDec 28 2011The paper aims to give an account, both historical and geometric, on the diverse geography of rational parametrizations of moduli spaces related to curves. It is a contribution to the book Handbook of Moduli, editors G. Farkas and I. Morrison, to be published ... More
A nonlinear Korn inequality based on the Green-Saint Venant strain tensorMay 23 2016A nonlinear Korn inequality based on the Green-Saint Venant strain tensor is proved, whenever the displacement is in the Sobolev space $W^{1,p}$, $p\geq 2$, under Dirichlet conditions on a part of the boundary. The inequality can be useful in proving ... More
ALICE OverviewNov 09 2017An overview of the recent results obtained by the ALICE Collaboration from the analysis of the pp, p-Pb and Pb-Pb data samples collected during LHC run I and the first half of run II is presented.
Maslov index of Hamiltonian systemsMay 09 2004Jan 17 2008The aim of this paper is to give an explicit formula in order to compute the Maslov index of the fundamental solution of a linear autonomous Hamiltonian system, in terms of the Conley-Zehnder index and the time one flow.
Maslov class and minimality in Calabi-Yau manifoldsJan 12 2000Generalizing the construction of the Maslov class for a Lagrangian embedding in a symplectic vector space, we prove that it is possible to give a consistent definition of this class for any Lagrangian submanifold of a Calabi-Yau manifold. Moreover, we ... More
Computing Quantiles in Regime-Switching Jump-Diffusions with Application to Optimal Risk Management: a Fourier Transform ApproachJul 29 2012In this paper we consider the problem of calculating the quantiles of a risky position, the dynamic of which is described as a continuous time regime-switching jump-diffusion, by using Fourier Transform methods. Furthermore, we study a classical option-based ... More
Fourier Transform Methods for Regime-Switching Jump-Diffusions and the Pricing of Forward Starting OptionsMay 23 2011In this paper we consider a jump-diffusion dynamic whose parameters are driven by a continuous time and stationary Markov Chain on a finite state space as a model for the underlying of European contingent claims. For this class of processes we firstly ... More
Hamiltonian Monte Carlo On Lie Groups and Constrained Mechanics on Homogeneous ManifoldsMar 11 2019Mar 14 2019In this paper we show that the Hamiltonian Monte Carlo method for compact Lie groups constructed in \cite{kennedy88b} using a symplectic structure can be recovered from canonical geometric mechanics with a bi-invariant metric. Hence we obtain the correspondence ... More
Simultaneous global exact controllability in projectionMar 02 2017Jun 04 2018We consider an infinite number of one dimensional bilinear Schr\"odinger equations in a segment. We prove the simultaneous global exact controllability in projection of unitarily equivalent sequences of functions.
O-minimal spectra, infinitesimal subgroups and cohomologyApr 09 2006By recent work on some conjectures of Pillay, each definably compact group $G$ in a saturated o-minimal expansion of an ordered field has a normal ``infinitesimal subgroup'' $G^{00}$ such that the quotient $G/G^{00}$, equipped with the ``logic topology'', ... More
Hodge duality operators on left covariant exterior algebras over two and three dimensional quantum spheresDec 29 2011Jun 04 2012Using non canonical braidings, we first introduce a notion of symmetric tensors and corresponding Hodge operators on a class of left covariant 3d differential calculi over the quantum SU(2) group, then we induce Hodge operators on the left covariant 2d ... More
Free fall and self-force: an historical perspectiveMay 04 2010Free fall has signed the greatest markings in the history of physics through the leaning Pisa tower, the Cambridge apple tree and the Einstein lift. The perspectives offered by the capture of stars by supermassive black holes are to be cherished, because ... More
Ground state energy of the low density Hubbard model. An upper boundNov 14 2006May 04 2007We derive an upper bound on the ground state energy of the three-dimensional (3D) repulsive Hubbard model on the cubic lattice agreeing in the low density limit with the known asymptotic expression of the ground state energy of the dilute Fermi gas in ... More
Time-reversal odd distribution functions in chiral models with vector mesonsJan 30 2005The so-called time-reversal odd distribution functions are known to be non-vanishing in QCD due to the presence of the link operator in the definition of these quantities. I show that T-odd distributions can be non-vanishing also in chiral models, if ... More
Models for transverse-momentum distributions and transversityNov 28 2011I present a short review of models for transverse-momentum distributions and transversity, with a particular attention on general features common to many models. I compare some model results with experimental extractions. I discuss the existence of relations ... More
GLACIER and related R&DJul 05 2011Liquid argon detectors, with mass up to 100 kton, are being actively studied in the context of proton decay searches, neutrino astrophysics and for the next generation of long baseline neutrino oscillation experiments to study the neutrino mass hierarchy ... More
Variational approximations for stationary states of Ising-like modelsJul 25 2013We introduce a new variational approach to the stationary state of kinetic Ising-like models. The approach is based on the cluster expansion of the entropy term appearing in a functional which is minimized by the system history. We rederive a known mean-field ... More
Deriving exact results for Ising-like models from the cluster variation methodSep 24 1999The cluster variation method (CVM) is an approximation technique which generalizes the mean field approximation and has been widely applied in the last decades, mainly for finding accurate phase diagrams of Ising-like lattice models. Here we discuss in ... More
Bubble propagation in a helicoidal molecular chainJul 26 2000We study the propagation of very large amplitude localized excitations in a model of DNA that takes explicitly into account the helicoidal structure. These excitations represent the ``transcription bubble'', where the hydrogen bonds between complementary ... More
On a Rigorous Proof of the Joos-Zeh Formula for Decoherence in a Two-Body ProblemJul 30 2003We consider a simple one dimensional system consisting of two particles interacting with a $\delta$-potential and we discuss a rigorous derivation of the asymptotic wave function of the system in the limit of small mass ratio. We apply the result to the ... More
A q-Virasoro Algebra at roots of unity, Free Fermions and Temperley Lieb HamiltoniansNov 05 2012In this work we introduce a novel q-deformation of the Virasoro algebra expressed in terms of free fermions, we then realize that this algebra, when the deformation parameter is a root of unity can be realized exactly on the lattice. We then study the ... More
The Nonlocal Involutive Charges of the CFT ${\cal M}_{3,4}$Oct 20 2009Nov 15 2010We consider continuum minimal ${\cal M}_{3,4} $ with central charge $c=1/2$. The eigenvalues of the known local involutive charges are known to be related to spectral zeta functions of suitable one dimensional shroedinger hamiltonians. We investigate ... More
Lattice Integrals of Motion of the Ising Model on the StripNov 12 2012We consider the 2D critical Ising model on a strip with fixed boundary conditions. It is shown that for a suitable reparametrization of the known Boltzmann weights the transfer matrix becomes a polynomial in the variable $\csc(4u)$, being $u$ the spectral ... More
Integrals of Motion for Critical Dense Polymers and Symplectic FermionsMar 29 2009Sep 07 2009We consider critical dense polymers ${\cal L}(1,2)$. We obtain for this model the eigenvalues of the local integrals of motion of the underlying Conformal Field Theory by means of Thermodynamic Bethe Ansatz. We give a detailed description of the relation ... More