Results for "M. Ballardini"

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Probing primordial features with the primary CMBJul 15 2018CMB photons travel from the last scattering surface, when the primary CMB has been generated, along the surface of the light cone to us. During their travel, they are affected by many secondary effects such as the integrated Sachs-Wolfe effect and CMB ... More
Probing primordial features with the primary CMBJul 15 2018Mar 08 2019CMB photons travel from the last scattering surface, when the primary CMB has been generated, along the surface of the light cone to us. During their travel, they are affected by many secondary effects such as the integrated Sachs-Wolfe effect and CMB ... More
Cosmological constraints on post-Newtonian parameters in effectively massless scalar-tensor theories of gravityJun 24 2019We study the cosmological constraints on the variation of the Newton's constant and on post-Newtonian parameters for simple models of scalar-tensor theory of gravity beyond the extended Jordan-Brans-Dicke theory. We restrict ourselves to an effectively ... More
Measuring ISW with next-generation radio surveysDec 04 2018Feb 13 2019The late-time integrated Sachs-Wolfe (ISW) signal in the CMB temperature anisotropies is an important probe of dark energy when it can be detected by cross-correlation with large-scale structure surveys. Because of their huge sky area, surveys in the ... More
A tutorial on Particle Swarm Optimization ClusteringSep 06 2018This paper proposes a tutorial on the Data Clustering technique using the Particle Swarm Optimization approach. Following the work proposed by Merwe et al. here we present an in-deep analysis of the algorithm together with a Matlab implementation and ... More
CMRNet: Camera to LiDAR-Map RegistrationJun 24 2019In this paper we present CMRNet, a realtime approach based on a Convolutional Neural Network to localize an RGB image of a scene in a map built from LiDAR data. Our network is not trained on the working area, i.e. CMRNet does not learn the map. Instead ... More
A conservative assessment of the current constraints on dark matter annihilation from Cosmic Rays and CMB observationsAug 31 2015In view of the current interest in combining different observations to constraint annihilating WIMP dark matter, we examine the relation between the Sommerfeld effect at the recombination epoch and in the galactic halo. By considering an up-to-date collection ... More
Constraining primordial non-Gaussianity using two galaxy surveys and CMB lensingJun 11 2019Next-generation galaxy surveys will be able to measure perturbations on scales beyond the equality scale. On these ultra-large scales, primordial non-Gaussianity leaves signatures that can shed light on the mechanism by which perturbations in the early ... More
CMB anisotropies generated by a stochastic background of primordial magnetic fields with non-zero helicityDec 04 2014Aug 08 2015We consider the impact of a stochastic background of primordial magnetic fields with non-vanishing helicity on CMB anisotropies in temperature and polarization. We compute the exact expressions for the scalar, vector and tensor part of the energy-momentum ... More
Probing primordial features with next-generation photometric and radio surveysDec 20 2017Apr 04 2018We investigate the possibility of using future photometric and radio surveys to constrain the power spectrum of primordial fluctuations that is predicted by inflationary models with a violation of the slow-roll phase. We forecast constraints with a Fisher ... More
Probing primordial features with future galaxy surveysJun 12 2016We study the capability of future measurements of the galaxy clustering power spectrum to probe departures from a power-law spectrum for primordial fluctuations. On considering the information from the galaxy clustering power spectrum up to quasi-linear ... More
A dataset for benchmarking vision-based localization at intersectionsNov 04 2018In this report we present the work performed in order to build a dataset for benchmarking vision-based localization at intersections, i.e., a set of stereo video sequences taken from a road vehicle that is approaching an intersection, altogether with ... More
ira_laser_tools: a ROS LaserScan manipulation toolboxNov 04 2014Laser scanners are sensors of widespread use in robotic applications. Under the Robot Operating System (ROS) the information generated by laser scanners can be conveyed by either LaserScan messages or in the form of PointClouds. Many publicly available ... More
Testing extended Jordan-Brans-Dicke theories with future cosmological observationsFeb 04 2019Jun 10 2019The extended Jordan-Brans-Dicke (eJBD) theory of gravity is constrained by a host of astrophysical and cosmological observations spanning a wide range of scales. The current cosmological constraints on the first post-Newtonian parameter in these simplest ... More
Testing extended Jordan-Brans-Dicke theories with future cosmological observationsFeb 04 2019The extended Jordan-Brans-Dicke (eJBD) theory of gravity is constrained by a host of astrophysical and cosmological observations spanning a wide range of scales. The current cosmological constraints on the first post-Newtonian parameter in these simplest ... More
Cosmological constraints on induced gravity dark energy modelsJan 13 2016We study induced gravity dark energy models coupled with a simple monomial potential $\propto \sigma^n$ and a positive exponent $n$. These simple potentials lead to viable dark energy models with a weak dependence on the exponent, which characterizes ... More
CMB and BAO constraints for an induced gravity dark energy model with a quartic potentialJul 02 2015We study the predictions for structure formation in an induced gravity dark energy model with a quartic potential. By developing a dedicated Einstein-Boltzmann code, we study self-consistently the dynamics of homogeneous cosmology and of linear perturbations ... More
Exploring Cosmic Origins with CORE: The InstrumentMay 05 2017May 22 2017We describe a space-borne, multi-band, multi-beam polarimeter aiming at a precise and accurate measurement of the polarization of the Cosmic Microwave Background. The instrument is optimized to be compatible with the strict budget requirements of a medium-size ... More
A comparison of Einstein-Boltzmann solvers for testing General RelativitySep 26 2017Dec 14 2017We compare Einstein-Boltzmann solvers that include modifications to General Relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general ... More
Planck 2018 results. VII. Isotropy and Statistics of the CMBJun 06 2019Analysis of the Planck 2018 data set indicates that the statistical properties of the cosmic microwave background (CMB) temperature anisotropies are in excellent agreement with previous studies using the 2013 and 2015 data releases. In particular, they ... More
CMRNet: Camera to LiDAR-Map RegistrationJun 24 2019Jul 17 2019In this paper we present CMRNet, a realtime approach based on a Convolutional Neural Network to localize an RGB image of a scene in a map built from LiDAR data. Our network is not trained in the working area, i.e. CMRNet does not learn the map. Instead ... More
Planck 2018 results. IX. Constraints on primordial non-GaussianityMay 14 2019We analyse the Planck full-mission cosmic microwave background (CMB) temperature and E-mode polarization maps to obtain constraints on primordial non-Gaussianity (NG). We compare estimates obtained from separable template-fitting, binned, and modal bispectrum ... More
On the ISW-cluster cross-correlation in future surveysDec 06 2017Nov 22 2018We investigate the cosmological information contained in the cross-correlation between the Integrated Sachs-Wolfe (ISW) of the Cosmic Microwave Background (CMB) anisotropy pattern and galaxy clusters from future wide surveys. Future surveys will provide ... More
Primordial Non-GaussianityMar 11 2019Mar 14 2019Our current understanding of the Universe is established through the pristine measurements of structure in the cosmic microwave background (CMB) and the distribution and shapes of galaxies tracing the large scale structure (LSS) of the Universe. One key ... More
Probing features in inflaton potential and reionization history with future CMB space observationsOct 03 2017Apr 04 2018We consider the prospects of probing features in the primordial power spectrum with future Cosmic Microwave Background (CMB) polarization measurements. In the scope of the inflationary scenario, such features in the spectrum can be produced by local non-smooth ... More
Cosmology with Phase 1 of the Square Kilometre Array; Red Book 2018: Technical specifications and performance forecastsNov 07 2018We present a detailed overview of the cosmological surveys that will be carried out with Phase 1 of the Square Kilometre Array (SKA1), and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift ... More
Planck intermediate results. LIV. Polarized dust foregroundsJan 15 2018The study of polarized dust emission has become entwined with the analysis of the cosmic microwave background (CMB) polarization. We use new Planck maps to characterize Galactic dust emission as a foreground to the CMB polarization. We present Planck ... More
Planck intermediate results. LIII. Detection of velocity dispersion from the kinetic Sunyaev-Zeldovich effectJul 01 2017Aug 23 2018Using the ${\it Planck}$ full-mission data, we present a detection of the temperature (and therefore velocity) dispersion due to the kinetic Sunyaev-Zeldovich (kSZ) effect from clusters of galaxies. To suppress the primary CMB and instrumental noise we ... More
Exploring Cosmic Origins with CORE: Extragalactic sources in Cosmic Microwave Background mapsSep 23 2016May 18 2017We discuss the potential of a next generation space-borne Cosmic Microwave Background (CMB) experiment for studies of extragalactic sources. Our analysis has particular bearing on the definition of the future space project, CORE, that has been submitted ... More
Planck intermediate results. LIV. The Planck Multi-frequency Catalogue of Non-thermal SourcesFeb 23 2018Sep 11 2018This paper presents the Planck Multi-frequency Catalogue of Non-thermal (i.e. synchrotron-dominated) Sources (PCNT) observed between 30 and 857 GHz by the ESA Planck mission. This catalogue was constructed by selecting objects detected in the full mission ... More
Exploring Cosmic Origins with CORE: B-mode Component SeparationApr 14 2017Jun 19 2017We demonstrate that, for the baseline design of the CORE satellite mission, the polarized foregrounds can be controlled at the level required to allow the detection of the primordial cosmic microwave background (CMB) $B$-mode polarization with the desired ... More
Exploring Cosmic Origins with CORE: Cluster ScienceMar 30 2017We examine the cosmological constraints that can be achieved with a galaxy cluster survey with the future CORE space mission. Using realistic simulations of the millimeter sky, produced with the latest version of the Planck Sky Model, we characterize ... More
Exploring cosmic origins with CORE: effects of observer peculiar motionApr 19 2017Aug 30 2017We discuss the effects on the CMB, CIB, and thermal SZ effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. We investigate the scientific perspectives opened by future CMB space missions, ... More
Exploring cosmic origins with CORE: mitigation of systematic effectsJul 13 2017We present an analysis of the main systematic effects that could impact the measurement of CMB polarization with the proposed CORE space mission. We employ timeline-to-map simulations to verify that the CORE instrumental set-up and scanning strategy allow ... More
Planck 2018 results. XI. Polarized dust foregroundsJan 15 2018Nov 12 2018The study of polarized dust emission has become entwined with the analysis of the cosmic microwave background (CMB) polarization. We use new Planck maps to characterize Galactic dust emission as a foreground to the CMB polarization. We present Planck ... More
Planck 2018 results. XII. Galactic astrophysics using polarized dust emissionJul 17 2018We present 353 GHz full-sky maps of the polarization fraction $p$, angle $\psi$, and dispersion of angles $S$ of Galactic dust thermal emission produced from the 2018 release of Planck data. We confirm that the mean and maximum of $p$ decrease with increasing ... More
Planck 2018 results. XII. Galactic astrophysics using polarized dust emissionJul 17 2018Mar 07 2019We present 353 GHz full-sky maps of the polarization fraction $p$, angle $\psi$, and dispersion of angles $S$ of Galactic dust thermal emission produced from the 2018 release of Planck data. We confirm that the mean and maximum of $p$ decrease with increasing ... More
Planck 2018 results. I. Overview and the cosmological legacy of PlanckJul 17 2018The European Space Agency's Planck satellite, which was dedicated to studying the early Universe and its subsequent evolution, was launched on 14 May 2009. It scanned the microwave and submillimetre sky continuously between 12 August 2009 and 23 October ... More
Planck intermediate results. XLIX. Parity-violation constraints from polarization dataMay 27 2016Aug 05 2016Parity violating extensions of the standard electromagnetic theory cause in vacuo rotation of the plane of polarization of propagating photons. This effect, also known as cosmic birefringence, impacts the cosmic microwave background (CMB) anisotropy angular ... More
Planck 2018 results. VI. Cosmological parametersJul 17 2018We present cosmological parameter results from the final full-mission Planck measurements of the CMB anisotropies. We find good consistency with the standard spatially-flat 6-parameter $\Lambda$CDM cosmology having a power-law spectrum of adiabatic scalar ... More
Planck intermediate results. LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parametersAug 08 2016Apr 21 2017The six parameters of the standard $\Lambda$CDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck ... More
Planck intermediate results. XLVI. Reduction of large-scale systematic effects in HFI polarization maps and estimation of the reionization optical depthMay 10 2016May 26 2016This paper describes the identification, modelling, and removal of previously unexplained systematic effects in the polarization data of the Planck High Frequency Instrument (HFI) on large angular scales, including new mapmaking and calibration procedures, ... More
Planck 2018 results. X. Constraints on inflationJul 17 2018We report on the implications for cosmic inflation of the 2018 Release of the Planck CMB anisotropy measurements. The results are fully consistent with the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements ... More
Planck 2018 results. IV. Diffuse component separationJul 17 2018We present full-sky maps of the cosmic microwave background (CMB) and polarized synchrotron and thermal dust emission, derived from the third set of Planck frequency maps. These products have significantly lower contamination from instrumental systematic ... More
Planck intermediate results. XLIV. The structure of the Galactic magnetic field from dust polarization maps of the southern Galactic capApr 04 2016We study the statistical properties of interstellar dust polarization at high Galactic latitude, using the Stokes parameter Planck maps at 353 GHz. Our aim is to advance the understanding of the magnetized interstellar medium (ISM), and to provide a model ... More
Planck 2018 results. III. High Frequency Instrument data processing and frequency mapsJul 17 2018This paper presents the High Frequency Instrument (HFI) data processing procedures for the Planck 2018 release. Major improvements in mapmaking have been achieved since the previous 2015 release. They enabled the first significant measurement of the reionization ... More
Planck 2016 intermediate results. LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parametersAug 08 2016The six parameters of the standard $\Lambda$CDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck ... More
Planck intermediate results. L. Evidence for spatial variation of the polarized thermal dust spectral energy distribution and implications for CMB $B$-mode analysisJun 23 2016The characterization of the Galactic foregrounds has been shown to be the main obstacle in the challenging quest to detect primordial B-modes in the polarized microwave sky. We make use of the Planck-HFI 2015 data release at high frequencies to place ... More
Planck intermediate results. XLVII. Planck constraints on reionization historyMay 11 2016Sep 05 2016We investigate constraints on cosmic reionization extracted from the Planck cosmic microwave background (CMB) data. We combine the Planck CMB anisotropy data in temperature with the low-multipole polarization data to fit LCDM models with various parameterizations ... More
Planck 2018 results. VIII. Gravitational lensingJul 17 2018We present measurements of the cosmic microwave background (CMB) lensing potential using the final $\textit{Planck}$ 2018 temperature and polarization data. We increase the significance of the detection of lensing in the polarization maps from $5\,\sigma$ ... More
Massive Neutrino in Non-commutative Space-timeDec 24 2007Apr 01 2008We consider the noncommutative standard model based on $SU(3)\times SU(2)\times U(1)$. We study the gauge transformation of right handed neutrino and its direct interaction with photon in the noncommutative space-time. We show that the massive Dirac neutrinos, ... More
Infinite order excitonic Bloch equations for asymmetric nanostructuresJul 04 2003We present a new exciton-based formalism for calculating the coherent response of asymmetric semiconductor multiple quantum well structures to ultra-short optical pulses valid to infinite order in the optical field and including the self-generated intraband ... More
Scalar StoponiumAug 18 1993We study the decays of a scalar \stst\ bound state \sigst, where \st\ is the lighter stop eigenstate. If \st\ has no tree--level 2--body decays, the dominant decay modes of \sigst\ are $gg$ or, if $m_h < \mst \ll \mstt$, a pair of light scalar Higgs bosons ... More
Planck intermediate results. XLVIII. Disentangling Galactic dust emission and cosmic infrared background anisotropiesMay 30 2016Aug 09 2016Using the Planck 2015 data release (PR2) temperature maps, we separate Galactic thermal dust emission from cosmic infrared background (CIB) anisotropies. For this purpose, we implement a specifically tailored component-separation method, the so-called ... More
Photon Neutrino Scattering in Non-Commutative SpaceNov 04 2005Jan 19 2006We extend the non-commutative standard model based on the minimal $SU(3)\times SU(2)\times U(1)$ gauge group to include the interaction of photon with neutrino. We show that, in the gauge invariant manner, only the right handed neutrino can directly couple ... More
Planck intermediate results. LII. Planet flux densitiesDec 21 2016Measurements of flux density are described for five planets, Mars, Jupiter, Saturn, Uranus, and Neptune, across the six Planck High Frequency Instrument frequency bands (100-857 GHz) and these are then compared with models and existing data. In our analysis, ... More
Planck 2018 results. II. Low Frequency Instrument data processingJul 17 2018Sep 11 2018We present a final description of the data-processing pipeline for the Planck, Low Frequency Instrument (LFI), implemented for the 2018 data release. Several improvements have been made with respect to the previous release, especially in the calibration ... More
A new signal for scalar top bound state productionOct 01 1993We study the production and decay of a scalar \stst\ bound state \sigst\ at hadron supercolliders, where \st\ is the lighter stop eigenstate. If \st\ has no tree--level 2--body decays, the dominant decay modes of \sigst\ are $gg$ or, if $m_h < \mst \ll ... More
Electroweak Baryogenesis in the MSSMMar 05 1999Mar 24 1999We review the baryogenesis scenario in the MSSM at the perturbative level and, in particular, the impact of two-loop corrections on the strength of the phase transition and the amount of generated baryon asymmetry. We confirm the baryogenesis window, ... More
Cosmic Variance and Its Effect on the Luminosity Function Determination in Deep High z SurveysDec 03 2007We study cosmic variance in deep high redshift surveys and its influence on the determination of the luminosity function for high redshift galaxies. For several survey geometries relevant for HST and JWST instruments, we characterize the distribution ... More
Periodic Solutions of Abel Differential EquationsMay 05 2006Jun 09 2006For a class of polynomial non-autonomous differential equations of degree n, we use phase plane analysis to show that each equation in this class has n periodic solutions. The result implies that certain rigid two-dimensional systems have at most one ... More
Hydrogen and muonic-Hydrogen Atomic Spectra in Non-commutative Space-TimeOct 03 2014Dec 16 2014Comparing electronic Hydrogen with muonic Hydrogen shows that the discrepancy in measurement of the Lamb shift in the both systems are relatively of order of $(\frac{m_\mu}{m_e})^{4-5}$. We explore the spectrum of Hydrogen atom in noncommutative $QED$ ... More
Pair excitations and the mean field approximation of interacting Bosons, IAug 18 2012Mar 16 2013In our previous work \cite{GMM1},\cite{GMM2} we introduced a correction to the mean field approximation of interacting Bosons. This correction describes the evolution of pairs of particles that leave the condensate and subsequently evolve on a background ... More
Color-Flavor (Un)lockingFeb 11 2002The structure of the phase diagram of strongly interacting matter at moderate densities is calculated within a 3-flavor NJL-type quark model with realistic quark masses. We focus on the influence of the selfconsistently determined effective strange quark ... More
Residual Diffeomorphisms and Symplectic Softs Hairs: The Need to Refine Strict Statement of Equivalence PrincipleMar 25 2016Sep 05 2016General covariance is the cornerstone of Einstein's General Relativity (GR) and implies that any two metrics related by diffeomorphisms are physically equivalent. There are, however, many examples pointing to the fact that this strict statement of general ... More
AGN pairs: chance superpositions or black hole binaries?Dec 29 2009Several active galactic nuclei (AGN) with multiple sets of emission lines separated by over 2000 km/s have been observed recently. These have been interpreted as being due to massive black hole (MBH) recoil following a black hole merger, MBH binaries, ... More
On Two Approaches to Fractional Supersymmetric Quantum MechanicsOct 26 2001Two complementary approaches of N = 2 fractional supersymmetric quantum mechanics of order k are studied in this article. The first one, based on a generalized Weyl-Heisenberg algebra W(k) (that comprizes the affine quantum algebra Uq(sl(2)) with q to ... More
Two-Photon Spectroscopy Between States of Opposite ParitiesNov 29 1995Magnetic- and electric-dipole two-photon absorption (MED-TPA), recently introduced as a new spectroscopic technique for studying transitions between states of opposite parities, is investigated from a theoretical point of view. A new approximation, referred ... More
Eisenstein series and quantum affine algebrasApr 26 1996Nov 23 1996Let X be a smooth projectibe curve over a finite field. We consider the Hall algebra H whose basis is formed by isomorphism classes of coherent sheaves on X and whose typical structure constant is the number of subsheaves in a given sheaf belonging to ... More
On the q-analog of homological algebraNov 04 1996This is an attempt to generalize some basic facts of homological algebra to the case of "complexes" in which the differential satisfies the condition $d^N=0$ instead of the usual $d^2=0$. Instead of familiar sign factors, the constructions related to ... More
Clusters of CyclesApr 07 2001A {\it cluster of cycles} (or {\it $(r,q)$-polycycle}) is a simple planar 2--co nnected finite or countable graph $G$ of girth $r$ and maximal vertex-degree $q$, which admits {\it $(r,q)$-polycyclic realization} on the plane, denote it by $P(G)$, i.e. ... More
Cosmic Electroweak StringsOct 27 1995We examine the Standard Model field configurations near cosmic strings in a particular class of models. This class is defined by the condition that the generator of the flux in the string, $T_s$, commutes with the Standard Model Lie algebra. We find that ... More
Instabilities of Electroweak StringsMay 22 1995We investigate the instabilities of low winding number electroweak strings using standard numerical techniques of linear algebra. For strings of unit winding we are able to confirm and extend existing calculations of the unstable region in the ($m_H/m_W,\sin^2\theta_W$) ... More
Searching for low weight pseudo-codewordsFeb 04 2007Jul 30 2007Belief Propagation (BP) and Linear Programming (LP) decodings of Low Density Parity Check (LDPC) codes are discussed. We summarize results of instanton/pseudo-codeword approach developed for analysis of the error-floor domain of the codes. Instantons ... More
Ground state spin and excitation energies in half-filled Lieb latticesOct 10 2016We present detailed spectral calculations for small Lieb lattices having up to $N=4$ number of cells, in the regime of half-filling, an instance of particular relevance for the nano-magnetism of discrete systems such as quantum dot arrays, due to the ... More
Shot noise in diffusive ferromagnetic metalsApr 05 2006We show that shot noise in a diffusive ferromagnetic wire connected by tunnel contacts to two ferromagnetic electrodes can probe the intrinsic density of states and the extrinsic impurity scattering spin-polarization contributions in the polarization ... More
Floquet scattering theory for current and heat noise in large amplitude adiabatic pumpsJul 12 2004Feb 05 2005We discuss the statistical correlation properties of currents and energy flows generated by an adiabatic quantum pump. Our approach emphasizes the important role of quantized energy exchange between the sea of electrons and the oscillating scatterer. ... More
Adiabatic quantum pump in the presence of external ac voltagesSep 28 2003We investigate a quantum pump which in addition to its dynamic pump parameters is subject to oscillating external potentials applied to the contacts of the sample. Of interest is the rectification of the ac currents flowing through the mesoscopic scatterer ... More
Heat production and current noise for single- and double-cavity quantum capacitorsMay 29 2009We analyze the frequency-dependent noise and the heat production rate for a dynamical quantum capacitor in the regime in which it emits single particles, electrons and holes. At low temperature and slow driving the relaxation resistance quantum, R_{q} ... More
Magnetic field symmetry of pump currents of adiabatically driven mesoscopic structuresFeb 03 2005Feb 20 2005We examine the scattering properties of a slowly and periodically driven mesoscopic sample using the Floquet function approach. One might expect that at sufficiently low driving frequencies it is only the frozen scattering matrix which is important. The ... More
Floquet scattering theory of quantum pumpsAug 19 2002We develop the Floquet scattering theory for quantum mechanical pumping in mesoscopic conductors. The nonequilibrium distribution function, the dc charge and heat currents are investigated at arbitrary pumping amplitude and frequency. For mesoscopic samples ... More
Excitation of surface dipole and solenoidal modes on toroidal structuresApr 27 2006May 01 2006The time dependent Schrodinger equation inclusive of curvature effects is developed for a spinless electron constrained to motion on a toroidal surface and subjected to circularly polarized and linearly polarized waves in the microwave regime. A basis ... More
Comment on ``Quasiparticle Spectra around a Single Vortex in a d-wave Superconductor''Oct 22 1997In a recent Letter Morita, Kohmoto and Maki analyzed the structure of quasiparticle states near a single vortex in a d-wave superconductor using an approximate version of the Bogoliubov - de Gennes theory. Their principal result is the existence of a ... More
Standard Model thermodynamics across the electroweak crossoverMar 17 2015Jul 23 2015Even though the Standard Model with a Higgs mass mH = 125 GeV possesses no bulk phase transition, its thermodynamics still experiences a "soft point" at temperatures around T = 160 GeV, with a deviation from ideal gas thermodynamics. Such a deviation ... More
Polyakov loop correlators from D0-brane interactions in bosonic string theoryMay 23 2005Jul 14 2005In this paper we re-derive the effective Nambu-Goto theory result for the Polyakov loop correlator, starting from the free bosonic string and using a covariant quantization. The boundary conditions are those of an open string attached to two D0-branes ... More
D-dimensional developed MHD turbulence: Double expansion modelMay 31 2006Developed magnetohydrodynamic turbulence near two dimensions $d$ up to three dimensions has been investigated by means of renormalization group approach and double expansion regularization. A modification of standard minimal subtraction scheme has been ... More
Eliminating overgrowth effects in Poisson spatial process through the correlation among actual nucleiMay 15 2003It has been shown that the KJMA (Kolmogorov-Johnson-Mehl-Avrami) solution of phase transition kinetics can be set as a problem of correlated nucleation [Phys.Rev.B65, 172301 (2002)]. In this paper the equivalence between the standard solution and the ... More
The electron gas with a strong pairing interaction: Three particle correlations and the Thouless instabilitySep 18 2000We derive simplified Faddeev type equations for the three particle T-matrix which are valid in the Hubbard model where only electrons with opposite spins interact. Using the approximation of dynamical mean field theory these equations are partially solved ... More
Antisymmetric and other subleading corrections to scaling in the local potential approximationDec 02 2001Dec 03 2001For systems in the universality class of the three-dimensional Ising model we compute the critical exponents in the local potential approximation (LPA), that is, in the framework of the Wegner-Houghton equation. We are mostly interested in antisymmetric ... More
Similarity and Dissimilarity between Influences of Anchoring Walls and of External Fields on Nematic and Smectic A PhasesDec 09 2004The McMillan liquid crystalline models under the influence of homeotropic anchoring walls and of external fields are investigated. For thin systems, the existence of the critical thickness, below which the system does not undergo a discrete phase transition, ... More
Double layers in gravity theoriesOct 21 2014Gravitational double layers, unlike their classical electromagnetic counterparts, are thought to be forbidden in gravity theories. It has been recently shown, however, that they are feasible in, for instance, gravity theories with a Lagrangian quadratic ... More
Singularity Theorems in General Relativity: Achievements and Open QuestionsApr 30 2006In this short note, a brief overview with a critical appraisal of the acclaimed singularity theorems, the most genuine post-Einsteinian result of General Relativity, is presented.
Radio Emission from Low Mass Young Stellar ObjectsOct 26 2012Compact radio emission provides a reliable method for the detection of low luminosity young stellar objects (YSOs), and is particularly useful for detecting the earliest stages of protostellar evolution where the source itself may still be heavily embedded ... More
Solutions of the Quantum-Yang-Baxter-Equation from Symmetric SpacesJul 03 2001We show that for each semi-Riemannian locally symmetric space the curvature tensor gives rise to a rational solution $r$ of the classical Yang-Baxter equation with spectral parameter. For several Riemannian globally symmetric spaces $M$ such as real, ... More
On quantum advantage in dense codingJan 18 2007Sep 11 2009The quantum advantage of dense coding is studied, considering general encoding quantum operations. Particular attention is devoted to the case of many senders, and it is shown that restrictions on the possible operations on the senders' side may make ... More
VON NEUMANN AND SHANNON-WEHRL ENTROPY FOR SQUEEZED STATES AND COSMOLOGICAL PARTICLE PRODUCTIONFeb 17 1995We show that the effective coarse graining of a two-mode squeezed density matrix, implicit in the Wehrl approaches to a semiclassical phase-space distribution, leads to results in agreement with previous different definitions of entropy for the process ... More
Symmetry-broken crystal structure of elemental boron at low temperatureDec 04 2007The crystal structure of boron is unique among chemical elements, highly complex, and imperfectly known. Experimentalists report the beta-rhombohedral (black) form is stable over all temperatures from absolute zero to melting. However, early calculations ... More
Order-disorder transition in the Cd-Ca cubic approximantFeb 13 2004Recent experiments discovered an order-disorder transition occuring at low temperatures in large unit 1/1 cell cubic approximants of the stable Cd-based binary alloy quasicrystals. The transition is related to correlations among orientational degrees ... More
Quark Model Calculations of the N to Delta ReactionJun 19 2015The electromagnetic excitation of the nucleon resonances is studied in the framework of Constituent Quark Models. Particular attention is devoted to the transition to the $\Delta$ resonance and to the issue of a possible deformation of hadronic systems, ... More
Electromagnetic multipoles - theory issuesJun 30 2015Some predictions of the Hypercentral Constituent Quark Model for the helicity amplitudes are discussed and compared with data and with the recent analysis of the Mainz group; the role of the pion cloud contribution in explaining the major part of the ... More