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Results for "Antonio Gens"

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A Hybrid multiphase model based on lattice Boltzmann method direct simulationsJun 11 2019By means of the multicomponent Shan-Chen lattice Boltzmann method (LBM), we investigate the multiphase flow through porous media. Despite the excellent accuracy of the LBM, large domains result in unaffordable computational expenses. The Hybrid model ... More
Bosonization and integral representation of solutions of the Knizhnik-Zamolodchikov-Bernard equationsSep 28 1998Jan 30 1999We construct an integral representation of solutions of the Knizhnik-Zamolodchikov-Bernard equations, using the Wakimoto modules.
The Schrodinger model for the minimal representation of the indefinite orthogonal group O(p, q)Dec 11 2007Jul 19 2008We introduce the `Fourier transform' F_C on the isotropic cone C associated to an indefinite quadratic form of signature (n_1,n_2) on R^n (n=n_1+n_2: even). This transform is in some sense the unique and natural unitary operator on L^2(C), as is the case ... More
Solvability of interior transmission problem for the diffusion equation by constructing its Green functionJun 15 2017Aug 01 2018Consider the interior transmission problem arising in inverse boundary value problems for the diffusion equation with discontinuous diffusion coefficients. We prove the unique solvability of the interior transmission problem by constructing its Green ... More
Wess-Zumino-Witten model on elliptic curves at the critical levelMay 14 2000We construct a Gaudin type lattice model as the Wess-Zumino-Witten model on elliptic curves at the critical level. Bethe eigenvectors are obtained by the bosonisation technique.
Cosmic evolution of scalar fields with multiple vacua: generalized DBI and quintessenceJan 28 2015Jun 08 2016We find a method to rewrite the equations of motion of scalar fields, generalized DBI field and quintessence, in the autonomous form for\emph{arbitrary} scalar potentials. With the aid of this method, we explore the cosmic evolution of generalized DBI ... More
Theory of spin transport through antiferromagnetic insulatorMar 18 2019A theoretical formulation for spin transport through an antiferromagnetic (AF) insulator is presented in the case driven/detected by direct/inverse spin Hall effect in two heavy metal contacts. The spin signal is shown to be transferred by the ferromagnetic ... More
Boundary determination of the Lamé moduli for the isotropic elasticity systemAug 02 2017We consider the inverse boundary value problem of determining the Lam\'e moduli of an isotropic, static elasticity equations of system at the boundary from the localized Dirichlet-to-Neumann map. Assuming appropriate local regularity assumptions as weak ... More
A Static Spherically Symmetric Solution of the Einstein-aether TheoryJan 30 2013Oct 25 2013By using of the Euler-Lagrange equations, we find a static spherically symmetric solution in the Einstein-aether theory with the coupling constants restricted. The solution is similar to the Reissner-Nordstrom solution in that it has an inner Cauchy horizon ... More
Entanglement extracted from vacuum into accelerated Unruh-DeWitt detectors and energy conservationJun 06 2019We consider a pair of two-level Unruh-DeWitt detectors accelerated uniformly in the Minkowski vacuum of a massless neutral scalar field, and analyze, within the perturbation theory, the entanglement extracted from the vacuum into the Unruh-DeWitt detectors ... More
Conditional Stability for Single Interior MeasurementJun 19 2013Aug 21 2013An inverse problem to identify unknown coefficients of a partial differential equation by a single interior measurement is considered. The equation considered in this paper is a strongly elliptic second order scalar equation which can have complex coefficients ... 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
Cyclic universe due to phantom and quintessenceFeb 17 2014Aug 14 2014We explore a cyclic universe due to phantom and quintessence fields. We find that, in every cycle of the evolution of the universe, the phantom dominates the cosmic early history and quintessence dominates the cosmic far future. In this model of universe, ... More
Fusion dynamics of symmetric systems near barrier energiesSep 06 2009The enhancement of the sub-barrier fusion cross sections was explained as the lowering of the dynamical fusion barriers within the framework of the improved isospin-dependent quantum molecular dynamics (ImIQMD) model. The numbers of nucleon transfer in ... More
Probing high-density behavior of symmetry energy from pion emission in heavy-ion collisionsApr 20 2009Jan 08 2010Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the emission of pion in heavy-ion collisions in the region 1 A GeV as a probe of nuclear symmetry energy at supra-saturation densities is investigated systematically, ... More
A hybrid inversion scheme of Markov-chain Monte Carlo and iterative methods for diffuse optical tomographyFeb 02 2018Diffuse optical tomography is formulated as inverse coefficient problems for the diffusion equation. Iterative inversion schemes such as the Levenberg-Marquardt algorithm are known to fail when initial guesses are not close to the true value of the coefficient ... More
Integrative Multi-View Reduced-Rank Regression: Bridging Group-Sparse and Low-Rank ModelsJul 26 2018Multi-view data have been routinely collected in various fields of science and engineering. A general problem is to study the predictive association between multivariate responses and multi-view predictor sets, all of which can be of high dimensionality. ... 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
Phonons and specific heat of linear dense phases of atoms physisorbed in the grooves of carbon nanotube bundlesDec 24 2002The vibrational properties (phonons) of a one-dimensional periodic phase of atoms physisorbed in the external groove of the carbon nanotube bundle are studied. Analytical expressions for the phonon dispersion relations are derived. The derived expressions ... More
Heavy Quarkonium Inclusive Decays: Theoretical Status and PerspectivesDec 18 2002I review some recent progress and open problems in the calculation of heavy-quarkonium inclusive decay widths into light particles in the framework of QCD non-relativistic effective field theories.
Constraints on very light sterile neutrinos from $θ_{13}$-sensitive reactor experimentsAug 27 2013Oct 31 2013Three dedicated reactor experiments, Double Chooz, RENO and Daya Bay, have recently performed a precision measurement of the third standard mixing angle $\theta_{13}$ exploiting a multiple baseline comparison of $\nu_e \to \nu_e$ disappearance driven ... More
Dynamical decompactification from brane gases in eleven-dimensional supergravitySep 08 2004Brane gas cosmology provides a dynamical decompactification mechanism that could account for the number of spacetime dimensions we observe today. In this work we discuss this scenario taking into account the full bosonic sector of eleven-dimensional supergravity. ... More
Late-time dynamics of brane gas cosmologyApr 25 2003Brane gas cosmology is a scenario inspired by string theory which proposes a simple resolution to the initial singularity problem and gives a dynamical explanation for the number of spatial dimensions of our universe. In this work we have studied analytically ... More
A New Keyboard for the Bohlen-Pierce ScaleNov 02 2011The study of harmonic scales of musical instruments is discussed in all introductory physics texts devoted to the science of sound. In this paper, we present a new piano keyboard to make the so-called Bohlen-Pierce scale more functional and pleasing for ... More
Extensions of Boolean isometriesMar 14 2009We study when a map between two subsets of a Boolean domain W can be extended to an automorphism of W. Under many hypotheses, if the underlying Boolean algebra is complete or if the sets are finite or Boolean domains, the necessary and suficient condition ... More
The Chemical Composition of the 30 Doradus Nebula Derived from VLT Echelle SpectrophotometryAug 28 2002Echelle spectrophotometry of the 30 Doradus nebula in the LMC is presented. The data consists of VLT UVES observations in the 3100 to 10350 A range. The intensities of 366 emission lines have been measured, including 269 identified permitted lines of ... More
A Cofibration Category on Closure SpacesAug 31 2017Jan 09 2018We construct a cofibration category structure on the category of closure spaces $\mathbf{Cl}$, the category whose objects are sets endowed with a \v{C}ech closure operator and whose morphisms are the continuous maps between them. We then study various ... More
Coevolution. Extending Prigogine TheoremSep 19 2006Apr 30 2008The formal consideration of the concept of interaction in thermodynamic analysis makes it possible to deduce, in the broadest terms, new results related to the coevolution of interacting systems, irrespective of their distance from thermodynamic equilibrium. ... More
Hilbert's machine and w-orderAug 14 2006Nov 23 2009Hilbert's machine is a supertask machine inspired by Hilbert's Hotel whose functioning leads to a contradictory result involving w-ordering.
On Bifurcated supertasks and related questionsJan 24 2010Jan 25 2012Bifurcated supertasks entail the actual infinite division of time (accelerated system of reference) as well as the existence of half-curves of infinite length (supertask system of reference). This paper analyzes both issues from a critique perspective. ... More
Graphene properties from curved space Dirac equationAug 03 2018Jan 18 2019A mathematical formulation for particle states and electronic properties of a curved graphene sheet is provided, exploiting a massless Dirac spectrum description for charge carriers living in a curved bidimensional background. In particular, we study ... More
A multiplicity result for the problem $δd ξ= f'(<ξ,ξ>)ξ$Jan 25 2007In this paper we consider the nonlinear equation involving differential forms on a compact Riemannian manifold $\delta d \xi = f'(<\xi,\xi>)\xi$. This equation is a generalization of the semilinear Maxwell equations recently introduced in a paper by Benci ... More
Event Driven Langevin simulations of Hard SpheresNov 26 2011Mar 08 2012The blossoming of interest in colloids and nano-particles has given renewed impulse to the study of hard-body systems. In particular, hard spheres have become a real test system for theories and experiments. It is therefore necessary to study the complex ... More
Iwasawa Theory for the Symmetric Square of a CM Modular Form at Inert PrimesDec 08 2010Aug 16 2011Let f be a CM modular form and p an odd prime which is inert in the CM field. We construct two p-adic L-functions for the symmetric square of f, one of which has the same interpolating properties as the one constructed by Delbourgo-Dabrowski, whereas ... More
On the representation of maps by Lie transformsNov 24 2012Mar 29 2013The problem of representing a class of maps in a form suited for application of normal form methods is revisited. It is shown that using the methods of Lie series and of Lie transform a normal form algorithm is constructed in a straightforward manner. ... More
Concentration and compactness in nonlinear Schrodinger-Poisson system with a general nonlinearityJun 29 2009In this paper we use a concentration and compactness argument to prove the existence of a nontrivial nonradial solution to the nonlinear Schrodinger-Poisson equations in R3, assuming on the nonlinearity the general hypotheses introduced by Berestycki ... More
Stable and isoperimetric regions in rotationally symmetric tori with decreasing Gauss curvatureApr 19 2006In this work we classify the stable regions (second order minima of perimeter under an area constraint) in tori of revolution with piecewise continuous decreasing Gauss curvature from the longest parallel and with a horizontal symmetry. Some applications ... More
A new bound on the Morse index of constant mean curvature tori of revolution in $\mathbb{S}^3$Feb 08 2011In this work we give a new lower bound on the Morse index for constant mean curvature tori of revolution immersed in the three-sphere $\mathbb{S}^3$, by computing some explicit negative eigenvalues for the corresponding Jacobi operator.
Linearly foliated Calabi-Yau n-folds I. First-order deformationsDec 04 2007We consider classes of noncompact n-folds with trivial canonical bundle, that are linear foliations on nonsingular projective varieties, in general without a projection to the base. We obtain them as first-order deformations of total spaces of vector ... More
Compact complete proper minimal immersions in strictly convex bounded regular domains of R^3Apr 30 2008Nov 19 2008Consider a strictly convex bounded regular domain $C$ of $\R^3$. For any arbitrary finite topological type we find a compact Riemann surface $\mathcal{M}$, an open domain $M\subset \mathcal{M}$ with the fixed topological type, and a conformal complete ... More
Iterative Filtering as a direct method for the decomposition of non-stationary signalsNov 08 2018The Iterative Filtering method is a technique developed recently for the decomposition and analysis of non-stationary and non-linear signals. In this work we propose two alternative formulations of the original algorithm which allows to transform the ... More
Probing and Distinguishing Representations at the LHCSep 03 2018The discovery made at the Large Hadron Collider (LHC) has revealed that the spontaneous symmetry breaking mechanism is realised in a gauge theory such as the Standard Model (SM) by at least one Higgs doublet. However, the possible existence of other scalar ... More
A Refined $\mathcal N=2$ Chiral Multiplet on Twisted ${\rm AdS}_2 \times S^1$Dec 28 2018Dec 31 2018We derive the partition function of an $\mathcal N = 2$ chiral multiplet on twisted ${\rm AdS}_2\times S^1$. The chiral multiplet is coupled to a background vector multiplet encoding a real mass deformation. We consider an ${\rm AdS}_2\times S^1$ metric ... More
The lepton anomaly in the presence of torsionMay 27 1997Apr 16 1998In the presence of a curved space-time with torsion, the divergence of the leptonic current gets new contributions from the curvature and the torsion in addition to those coming from the electroweak fields. However it is possible to define a new lepton ... More
Factorisation of two-variable p-adic L-functionsApr 28 2013Let $f$ be a modular form which is non-ordinary at $p$. Kim and Loeffler have recently constructed two-variable $p$-adic $L$-functions associated to $f$. In the case where $a_p=0$, they showed that, as in the one-variable case, Pollack's plus and minus ... More
Critical phenomena of thick branes in warped spacetimesNov 22 2001Apr 15 2002We have investigated the effects of a generic bulk first-order phase transition on thick Minkowski branes in warped geometries. As occurs in Euclidean space, when the system is brought near the phase transition an interface separating two ordered phases ... More
Light neutral mesons production in p-A collisions at $\sqrt{s} = 27.5$ GeV with the NA60 ExperimentDec 31 2011The NA60 experiment has studied low-mass muon pair production in proton-nucleus (p-A) collisions with a system of Be, Cu, In, W, Pb and U targets using a 400 GeV/$c$ proton beam at the CERN SPS. Thanks to the collected data sample of 180\,000 low mass ... More
Aspects of particle mixing in Quantum Field TheoryAug 30 2004Sep 06 2004The results obtained on the particle mixing in Quantum Field Theory are reviewed. The Quantum Field Theoretical formulation of fermion and boson mixed fields is analyzed in detail and new oscillation formulas exhibiting corrections with respect to the ... More
New results on inclusive quarkonium decaysMay 13 2002I review some recent progress, leading to a substantial reduction in the number of non-perturbative parameters, in the calculation of inclusive quarkonium decay widths in the framework of non-relativistic effective field theories.
Superstripes in the Low Energy Physics of Complex Quantum Matter at the MesoscaleMar 10 2015Mar 12 2015Quantum physics in the 20th century was proposed to understand the phenomenology of atomic world at short length scale (below one nanometer) and it was developed to study nuclear and subnuclear world at the lowest possible spatial scale and at the highest ... More
On the Beauville form of the known irreducible symplectic varietiesJun 16 2006We study the global geometry of the ten dimensional O'Grady irreducible symplectic variety. We determine its second Betti number, its Beauville form and its Fujiki constant.
A real viewpoint on the intersection of complex quadrics and its topologyJun 09 2011We study the relation between a complex projective set C in CP^n and the set R in RP^(2n+1) defined by viewing each equation of C as a pair of real equations. Once C is presented by quadratic equations, we can apply a spectral sequence to efficiently ... More
More about Electroweak Baryogenesis in the Minimal Supersymmetric Standard ModelSep 08 1997We compute the baryon asymmetry generated at the electroweak phase transition by the Higgs scalar sector of the minimal supersymmetric standard model. Because of large enhancement effects from low momentum modes, Higgs particles may be responsible for ... More
Towards a Nonequilibrium Quantum Field Theory Approach to Electroweak BaryogenesisOct 11 1995We propose a general method to compute $CP$-violating observables from extensions of the standard model in the context of electroweak baryogenesis. It is alternative to the one recently developed by Huet and Nelson and relies on a nonequilibrium quantum ... More
Radiative transitions and the quarkonium magnetic momentAug 30 2006I discuss heavy quarkonium radiative transitions and the related issue of the quarkonium magnetic moment inside effective field theories. Differences in set up and conclusions with respect to typical phenomenological approaches are outlined.
The heavy quark potential in pNRQCDSep 20 1999The heavy quarkonium static potential is discussed within the framework of potential NRQCD. Some quantitative statements are made in the kinematical situation $mv >> \Lambda_{\rm QCD}$ at the level of accuracy of the next-to-leading order in the multipole ... More
The Barbieri-Remiddi solution of the bound state problem in QEDJul 22 1998We derive the so-called Barbieri-Remiddi solution of the Bethe-Salpeter equation in QED in its general form and discuss its application to the bound state energy spectrum.
The quark-antiquark Wilson loop formalism in the NRQCD power counting schemeSep 02 1998The quark-antiquark interaction from the NRQCD Lagrangian is studied in the Wilson loop formalism.
Singular integrals and maximal functions: the disk multiplier revisitedOct 23 2013Dec 18 2013Several estimates for singular integrals, maximal functions and the spherical summation operator are given in the spaces $L^p_{\text{rad}}L^2_{\text{ang}}(\mathbb{R}^n)$, $n\geq 2$.
A theoretical review of heavy quarkonium inclusive decaysNov 24 2003Jan 22 2004In this brief review, I summarize the current theoretical knowledge of heavy quarkonium inclusive decays, with emphasis on recent progress made in the framework of QCD effective field theories. In appendix, I list the imaginary parts of the matching coefficients ... More
New universal attractor in nonmininally coupled gravity: Linear inflationJan 26 2018Jul 17 2018Once quantum corrections are taken into account, the strong coupling limit of the $\xi$-attractor models (in metric gravity) might depart from the usual Starobinsky solution and move into linear inflation. Furthermore, it is well known that the metric ... More
Nested-set inconsistencyApr 26 2010Jan 25 2012This paper examines a denumerable version of the nested-set theorem and derives from it a contradiction involving the formal consistency of the actual infinity assumed by the Axiom of Infinity.
Living beings as informed systems: towards a physical theory of informationSep 19 2006I propose here a new concept of information based on two relevant aspects of its expression. The first related to the undeniable fact that the expression of information modifies the physical state of its receiver. The second to the arbitrariness of such ... More
Coleman Maps for Modular Forms at Supersingular Primes over Lubin-Tate ExtensionsAug 01 2009Jul 12 2010Given an elliptic curve with supersingular reduction at an odd prime p, Iovita and Pollack have generalised results of Kobayashi to define even and odd Coleman maps at p over Lubin-Tate extensions given by a formal group of height 1. We generalise this ... More
Unipotent representations of Lie incidence geometriesJul 25 2013If a geometry $\Gamma$ is isomorphic to the residue of a point $A$ of a shadow geometry of a spherical building $\Delta$, a representation $\varepsilon_\Delta^A$ of $\Gamma$ can be given in the unipotent radical $U_{A^*}$ of the stabilizer in $\mathrm{Aut}(\Delta)$ ... More
Height estimates for constant mean curvature graphs in $\mathrm{Nil}_3$ and $\widetilde{PSL}_2(\mathbb{R})$Mar 18 2018Mar 18 2019In this paper we obtain height estimates for compact, constant mean curvature vertical graphs in the homogeneous spaces $\mathrm{Nil}_3$ and $\widetilde{PSL}_2(\mathbb{R})$. As a straightforward consequence, we announce a structure-type result for proper ... More
A Delaunay-type classification result for prescribed mean curvature surfaces in $\mathbb{M}^2(κ)\times\mathbb{R}$Jul 26 2018May 15 2019The purpose of this paper is to study immersed surfaces in the product spaces $\mathbb{M}^2(\kappa)\times\mathbb{R}$, whose mean curvature is given as a $C^1$ function depending on their angle function. This class of surfaces extends widely, among others, ... More
On the Existence of Absolutely Maximally Entangled States of Minimal Support IIJun 30 2018Absolutely maximally entangled, AME, states are pure multipartite states that give rise to the maximally mixed states when half or more of the parties are traced out. AME states find applications in fields like teleportation or quantum secret sharing, ... More
Total and geometric phases, Majorana and Dirac neutrinosApr 11 2019The analysis of the total and geometric phases generated by the neutrino oscillation shows that these phases for Majorana neutrinos are depending on the representation of the mixing matrix and they are different from those of Dirac neutrinos.
R&D studies on eco-friendly gas mixtures for the ALICE Muon IdentifierJun 05 2018Resistive Plate Chambers (RPCs), used for the Muon Spectrometer of the ALICE experiment at CERN LHC, are currently operated in maxi-avalanche mode with a low threshold value and without amplification in the front-end electronics. RPC detectors have shown ... More
Limb and gravity-darkening coefficients for the TESS satellite at several metallicities, surface gravities, and microturbulent velocitiesApr 26 2018We present new gravity and limb-darkening coefficients for a wide range of effective temperatures, gravities, metallicities, and microturbulent velocities. These coefficients can be used in many different fields of stellar physics as synthetic light curves ... More
Prediction in Cyber Security: Complications and ConsolationsApr 23 2018Apr 25 2018Uncertainty, error, and similar complications add to the many challenges of cyber security. Various disciplines have developed methods for managing these complications, but applying these methods involves disambiguating overlapping terminology and determining ... More
On a prescribed mean curvature equation in Lorentz-Minkowski spaceJun 25 2015We are interested in providing new results on a prescribed mean curvature equation in Lorentz-Minkowski space set in the whole R^N, with N >2. We study both existence and multiplicity of radial ground state solutions for p>1, emphasizing the fundamental ... More
On the structure of complete kählerian manifolds furnished with closed conformal vector fieldsSep 19 2014May 29 2017We show that if a connected compact k\"ahlerian surface $M$ with nonpositive gaussian curvature is furnished with a closed conformal vector field $\xi$ whose singular points are isolated, then $M$ is isometric to a flat torus and $\xi$ is parallel. We ... More
On the Calabi-Yau problem for maximal surfaces in L^3Jul 09 2007Dec 04 2007In this paper we construct an example of a weakly complete maximal surface in the Lorentz-Minkowski space L^3, which is bounded by a hyperboloid. Moreover, all the singularities of our example are of lightlike type.
On the canonical discussion of polynomial systems with parametersJan 27 2006May 09 2007Given a parametric polynomial ideal I, the algorithm DISPGB, introduced by the author in 2002, builds up a binary tree describing a dichotomic discussion of the different reduced Groebner bases depending on the values of the parameters, whose set of terminal ... 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
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
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