Results for "S. Riccò"

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Band Structure and Spin-Orbital Texture of the (111)-KTaO3 Two-Dimensional Electron GasMar 14 2019Two-dimensional electron gases (2DEGs) in oxides show great potential for discovering new physical phenomena and at the same time hold promise for electronic applications. In this work we use angle resolved photoemission to determine the electronic structure ... More
Persistence of antiferromagnetic order upon La substitution in the $4d^4$ Mott insulator Ca$_2$RuO$_4$May 15 2018Jun 28 2018The chemical and magnetic structures of the series of compounds Ca$_{2-x}$La$_x$RuO$_4$ [$x = 0$, $0.05(1)$, $0.07(1)$, $0.12(1)$] have been investigated using neutron diffraction and resonant elastic x-ray scattering. Upon La doping, the low temperature ... More
A portable electronic system for in-situ measurements of oil concentration in MetalWorking fluidsMar 23 2016MetalWorking Fluids (MWFs) are widely used to cool and lubricate machines and tools. By far, the most common MWFs are oil-in-water emulsions with oil concentration (C oil) in the range from 1% to 10%, depending on type of oil, material to be worked, etc. ... More
Recovering Metallicity in A4C60: The Case of Monomeric Li4C60Jan 15 2007The restoration of metallicity in the high-temperature, cubic phase of Li4C60 represents a remarkable feature for a member of the A4C60 family (A = alkali metal), invariably found to be insulators. Structural and resonance technique investigations on ... More
An optically stimulated superconducting-like phase in K3C60 far above equilibrium TcMay 18 2015The control of non-equilibrium phenomena in complex solids is an important research frontier, encompassing new effects like light induced superconductivity. Here, we show that coherent optical excitation of molecular vibrations in the organic conductor ... More
In-situ strain-tuning of the metal-insulator-transition of Ca$_{2}$RuO$_{4}$ in angle-resolved photoemission experimentsMar 01 2018Oct 24 2018We report the evolution of the $k$-space electronic structure of lightly doped bulk Ca$_{2}$RuO$_{4}$ with uniaxial strain. Using ultrathin plate-like crystals, we achieve strain levels up to $-4.1\%$, sufficient to suppress the Mott phase and access ... More
Absence of Giant Spin Splitting in the Two-Dimensional Electron Liquid at the Surface of SrTiO$_3$ (001)Mar 01 2016We reinvestigate the putative giant spin splitting at the surface of SrTiO$_3$ reported by Santander-Syro $et~al.$ [Nature Mat. 13, 1085 (2014)]. Our spin- and angle-resolved photoemission experiments on (001) oriented surfaces supporting a two-dimensional ... More
Observation of Large Topologically Trivial Fermi-Arcs in the Candidate Type-II Weyl Semimetal WTe2Apr 08 2016Sep 12 2016We report angle-resolved photoemission experiments resolving the distinct electronic structure of the inequivalent top and bottom (001) surfaces of WTe2. On both surfaces, we identify a surface state that forms a large Fermi-arc emerging out of the bulk ... More
Electronic structure of buried LaNiO3 layers in (111)-oriented LaNiO3/LaMnO3 superlattices probed by soft x-ray ARPESNov 25 2016Taking advantage of the large electron escape depth of soft x-ray angle resolved photoemission spectroscopy we report electronic structure measurements of (111)-oriented [LaNiO3/LaMnO3] superlattices and LaNiO3 epitaxial films. For thin films we observe ... More
Tailoring the nature and strength of electron-phonon interactions in the SrTiO$_3$(001) two-dimensional electron liquidJun 03 2015Feb 19 2016Surfaces and interfaces offer new possibilities for tailoring the many-body interactions that dominate the electrical and thermal properties of transition metal oxides. Here, we use the prototypical two-dimensional electron liquid (2DEL) at the SrTiO$_3$(001) ... More
NMR study of the Superconducting gap variation near the Mott transition in Cs$_{3}$C$_{60}$Oct 21 2013Feb 19 2014Former extensive studies of superconductivity in the \textit{A}$_{3}$C$_{60}$ compounds, where \textit{A} is an alkali, have led to consider that Bardeen Cooper Schrieffer (BCS) electron-phonon pairing prevails in those compounds, though the incidence ... More
Spin Dynamics at the Mott Transition and in the Metallic State of the Cs_{3}C_{60} Superconducting PhasesFeb 28 2011We present here ^{13}C and ^{133}Cs NMR spin lattice relaxation T_{1} data in the A15 and fcc-Cs_{3}C_{60} phases for increasing hydrostatic pressure through the transition at p_{c} from a Mott insulator to a superconductor. We evidence that for p>> p_{c} ... More
Mott transition in the A15 phase of Cs$_{3} $C$_{60}$: absence of pseudogap and charge orderOct 03 2016We present a detailed NMR study of the insulator to metal transition induced by an applied pressure $p$ in the A15 phase of Cs$_{3}$C$_{60}$. We evidence that the insulating antiferromagnetic (AF) and superconducting (SC) phases only coexist in a narrow ... More
Pressure tuning of light-induced superconductivity in K3C60May 16 2017Mar 08 2018Optical excitation at terahertz frequencies has emerged as an effective means to manipulate complex solids dynamically. In the molecular solid K3C60, coherent excitation of intramolecular vibrations was shown to transform the high temperature metal into ... More
Electronic and ionic conductivities in superionic Li$_4$C$_{60}$Mar 04 2016The $10$ GHz microwave conductivity, $\sigma(T)$ and high field, $222$ GHz electron spin resonance (HF-ESR) of Li$_4$C$_{60}$ fulleride is measured in a wide temperature range. We suggest that the majority of ESR active sites and at least some of the ... More
Band insulator to Mott insulator transition in a bilayer Hubbard modelMar 27 2007The ground state phase diagram of the half-filled repulsive Hubbard model in a bilayer is investigated using cluster dynamical mean field theory. For weak to intermediate values of Coulomb repulsion $U$, the system undergoes a transition from a Mott insulating ... More
Modelling the VHE flare of 3C 279 using one zone leptonic modelSep 12 2011We model the simultaneous observations of the flat spectrum radio quasar 3C 279 at radio, optical, X-ray and very high energy (VHE) gamma ray energies during 2006 flare using a simple one zone leptonic model. We consider synchrotron emission due to cooling ... More
Tachyon Matter in Boundary String Field TheoryMay 09 2002May 18 2002We analyse the classical decay process of unstable D-branes in superstring theory using the boundary string field theory (BSFT) action. We show that the solutions of the equations of motion for the tachyon field asymptotically approach to T=x^0 and the ... More
The Cauchy problem for metric-affine f(R)-gravity in presence of a Klein-Gordon scalar fieldMar 22 2010We study the initial value formulation of metric-affine f(R)-gravity in presence of a Klein-Gordon scalar field acting as source of the field equations. Sufficient conditions for the well-posedness of the Cauchy problem are formulated. This result completes ... More
Low metallicity AGB models: H profile in the 13C-pocket and the effect on the s-processMay 17 2010The 13C(a, n)16O reaction is the major neutron source in low mass asymptotic giant branch (AGB) stars, where the main and the strong s process components are synthesised. After a third dredge-up (TDU) episode, 13C burns radiatively in a thin pocket which ... More
What Is Boolean Valued Analysis?Oct 05 2006May 08 2009This is a brief overview of the basic techniques of Boolean valued analysis.
Expected Number of Slope Crossings of Certain Gaussian Random PolynomialsDec 31 2006Let $Q_n(x)=\sum_{i=0}^{n} A_{i}x^{i}$ be a random polynomial where the coefficients $A_0,A_1,... $ form a sequence of centered Gaussian random variables. Moreover, assume that the increments $\Delta_j=A_j-A_{j-1}$, $j=0,1,2,...$ are independent, assuming ... More
On the Average Number of Sharp Crossings of Certain Gaussian Random PolynomialsMay 27 2006Let $Q_n(x)=\sum_{i=0}^{n} A_{i}x^{i}$ be a random algebraic polynomial where the coefficients $A_0,A_1,... $ form a sequence of centered Gaussian random variables. Moreover, assume that the increments $\Delta_j=A_j-A_{j-1}$, $j=0,1,2,...$ are independent, ... More
An iterated sum formula for a spheroid's homotopy class modulo 2-torsionJun 21 2006Let $X$ be a simply connected pointed space with finitely generated homotopy groups. Let $\Pi_n(X)$ denote the set of all continuous maps $a:I^n\to X$ taking $\partial I^n$ to the basepoint. For $a\in\Pi_n(X)$, let $[a]\in\pi_n(X)$ be its homotopy class. ... More
Technological Strategy of Using Global Positioning System: An AnalysisJan 23 2010The Global Positioning System (GPS) is a U.S. space-based radionavigation system that provides reliable positioning, navigation, and timing services to civilian users on a continuous worldwide basis -- freely available to all. GPS provides specially coded ... More
Resonating valence bond wave function for the two dimensional fractional spin liquidAug 13 2003Feb 19 2004The unconventional low-lying spin excitations, recently observed in neutron scattering experiments on ${\rm Cs_2 Cu Cl_4}$, are explained with a spin liquid wave function. The dispersion relation as well as the wave vector of the incommensurate spin correlations ... More
Enhanced signal propagation in a network with unidirectional and random couplingsApr 22 2014We investigate the effect of unidirectional regular and random couplings of units in a network on stochastic resonance. For simplicity we choose the units as Bellows map with bistability. In a regular network we apply a weak periodic signal and noise ... More
On $T$-sequences and characterized subgroupsFeb 04 2009Mar 08 2009Let $X$ be a compact metrizable abelian group and $\mathbf{u}=\{u_n\}$ be a sequence in its dual $X^{\wedge}$. Set $s_{\mathbf{u}} (X)= \{x: (u_n,x)\to 1\}$ and $\mathbb{T}_0^H = \{(z_n)\in \mathbb{T}^{\infty} : z_n\to 1 \}$. Let $G$ be a subgroup of ... More
On the Ascoli property for locally convex spaces and topological groupsNov 09 2016We characterize Ascoli spaces by showing that a Tychonoff space $X$ is Ascoli iff the canonical map from the free locally convex space $L(X)$ over $X$ into $C_k\big( C_k(X)\big)$ is an embedding of locally convex spaces. We prove that an uncountable direct ... More
Quotient Equations and Integrals of Motion for Massive Spinor FieldMar 29 2003In this article a group-theoretical aspect of the method of dimensional reduction is presented. Then, on the base of symmetry analysis of an anisotropic space geometrical description of dimensional reduction of equation for massive spinor field is given. ... More
Soft wall model with inverse exponential profile as a model for the axial and pseudoscalar mesonsJul 11 2012According to the conjecture of the gauge/gravity duality a strongly coupled 4D field theory may be described by a dual 5D theory which is a free field theory in the first approximation. The usual description of the axial-vector sector in the bottom-up ... More
No-Wall Holographic Model for QCDDec 22 2010Mar 03 2011We propose a new type of bottom-up holographic model describing the Regge like spectrum of mesons. This type of spectrum emerges due to condensation of a scalar field in the bulk anti-de Sitter space. The gauge invariance of the action describing the ... More
Holographic like models as a five-dimensional rewriting of large-Nc QCDJan 18 2010Oct 13 2010The AdS/QCD models are known to be tightly related with the QCD sum rules in the large-Nc (called also planar) limit. Rewriting the theory of infinite tower of free stable mesons expected in the large-Nc QCD as a five-dimensional theory we scrutinize ... More
About the possibility of five-dimensional effective theories for low-energy QCDMar 18 2009The AdS/QCD models suggest an interesting idea that the effective theory of low-energy QCD may be formulated as a 5-dimensional field theory in the weak coupling regime in which the fifth coordinate plays a role of inverse energy scale. Taking the point ... More
A five-dimensional toy-model for light hadron excitationsAug 04 2009Jun 17 2010In the usual holographic approach to QCD, the meson spectrum is generated due to a non-trivial 5-dimensional background. We propose an alternative 5-dimensional scenario in which the spectrum emerges due to coupling to a scalar field whose condensation ... More
Properties of new unflavored mesons below 2.4 GeVJul 05 2007The global features of spectrum of highly excited light nonstrange mesons can be well understood within both chiral symmetry restoration scenario combined with the relation $M^2\sim J+n$ and within nonrelativistic description based on the relation $M^2\sim ... More
The Call of MathematicsMay 28 2007A few remarks on how mathematics quests for freedom.
Saunders Mac Lane, the Knight of MathematicsJul 11 2005This is a short obituary of Saunders Mac Lane (1909--2005).
The Mathematical Background of Lomonosov's ContributionApr 14 2011This is a short overview of the influence of mathematicians and their ideas on the creative contribution of Mikhailo Lomonosov on the occasion of the tercentenary of his birth.
Energy flows in vibrated granular mediaMay 20 1998We study vibrated granular media, investigating each of the three components of the energy flow: particle-particle dissipation, energy input at the vibrating wall, and particle-wall dissipation. Energy dissipated by interparticle collisions is well estimated ... More
Energy non-equipartition in systems of inelastic, rough spheresMay 20 1998We calculate and verify with simulations the ratio between the average translational and rotational energies of systems with rough, inelastic particles, either forced or freely cooling. The ratio shows non-equipartition of energy. In stationary flows, ... More
Nucleon participants or quark participants?Feb 24 2003May 07 2003We show that centrality dependence of charged particle pseudorapidity density at midrapidity in Au+Au collisions at RHIC is well described as proportional to We show that centrality dependence of charged particle pseudorapidity density at midrapidity ... More
BPS Saturated String Amplitudes: K3 Elliptic Genus and Igusa Cusp FormAug 01 2011Nov 15 2011We study BPS saturated one-loop amplitudes in type II string theory compactified on K3 x T^2. The classes of amplitudes we consider are only sensitive to the very basic topological data of the internal K3 manifold. As a consequence, the integrands of ... More
Uses of Linear Polarization as a Probe of Extrasolar Planet AtmospheresMay 22 2003We point out some advantages of making observations of extrasolar planets in linearly polarized (LP) light. Older cool stars have quite low levels (~ 10^-4 to 10^-5) of fractional LP, while extrasolar planets can have relatively high fractional LP (~0.1). ... More
CP-violation in K_{S,L}->π^{+}π^{-}γand K_{S,L}->π^{+}π^{-}e^{+}e^{-} decaysSep 04 2001Apr 27 2002The dependence of K_{S,L}->\pi^{+}\pi^{-}\gamma decay probabilities on photon polarization is calculated. The phases of terms of amplitude that arise from the pion-pion interaction are obtained by using a simple realistic model of pion-pion interaction ... More
Caldirola-Kanai Oscillator in Classical Formulation of Quantum MechanicsFeb 23 1998The quadrature distribution for the quantum damped oscillator is introduced in the framework of the formulation of quantum mechanics based on the tomography scheme. The probability distribution for the coherent and Fock states of the damped oscillator ... More
Magnetic dissipation in the Crab NebulaJul 13 2012Oct 15 2012Magnetic dissipation is frequently invoked as a way of powering the observed emission of relativistic flows in Gamma Ray Bursts and Active Galactic Nuclei. Pulsar Wind Nebulae provide closer to home cosmic laboratories which can be used to test the hypothesis. ... More
Magnetic acceleration of relativistic jetsJun 11 2010This is a brief review of the recent developments in the theory of magnetic acceleration of relativistic jets. We attempt to explain the key results of this complex theory using basic physical arguments and simple calculations. The main focus is on the ... More
Magnetized Tori around Kerr Black Holes: Analytic Solutions with a Toroidal Magnetic FieldJan 30 2006Mar 01 2006The dynamics of accretion discs around galactic and extragalactic black holes may be influenced by their magnetic field. In this paper we generalise the fully relativistic theory of stationary axisymmetric tori in Kerr metric of Abramowicz et al.(1978) ... More
On the Properties of Time-Dependent, Force-Free, Degenerate ElectrodynamicsFeb 25 2002This paper formulates time-dependent, force-free, degenerate electrodynamics as a hyperbolic system of conservation laws. It is shown that this system has four characteristic modes, a pair of fast waves propagating with the speed of light and a pair of ... More
Observations of the Blandford-Znajek and the MHD Penrose processes in computer simulations of black hole magnetospheresJan 27 2005In this paper we report the results of axisymmetric relativistic MHD simulations for the problem of Kerr black hole immersed into a rarefied plasma with ''uniform'' magnetic field. The long term solution shows properties which are significantly different ... More
The Effects of Radiation Feedback on Early Fragmentation and MultiplicityOct 20 2010Forming stars emit a significant amount of radiation into their natal environment. While the importance of radiation feedback from high-mass stars is widely accepted, radiation has generally been ignored in simulations of low-mass star formation. I use ... More
Star Formation in ClustersAug 11 2004HST is very well tailored for observations of extragalactic star clusters. One obvious reason is HST's high spatial resolution, but equally important is the wavelength range offered by the instruments on board HST, in particular the blue and near-UV coverage ... More
Young massive star clusters in nearby galaxies. II.Software tools, data reductions and cluster sizesJul 13 1999A detailed description is given of the data analysis leading to the discovery of young massive star clusters (YMCs) in a sample of 21 nearby galaxies. A new useful tool, ishape, for the derivation of intrinsic shape parameters of compact objects is presented, ... More
The $B-L$ Supersymmetric Standard Model with Inverse Seesaw at the Large Hadron ColliderMar 27 2015Oct 24 2015We review the TeV scale $B-L$ extension of the Minimal Supersymmetric Standard Model (BLSSM) where an inverse seesaw mechanism of light neutrino mass generation is naturally implemented and concentrate on its hallmark manifestations at the Large Hadron ... More
Robust Radio Interferometric Calibration Using the t-DistributionJul 18 2013A major stage of radio interferometric data processing is calibration or the estimation of systematic errors in the data and the correction for such errors. A stochastic error (noise) model is assumed, and in most cases, this underlying model is assumed ... More
The light-front coupled-cluster method applied to $φ_{1+1}^4$ theoryOct 02 2014We use the light-front coupled-cluster (LFCC) method to compute the odd-parity massive eigenstate of $\phi_{1+1}^4$ theory. A standard Fock-space truncation of the eigenstate yields a finite set of linear equations for a finite number of wave functions. ... More
A brief introduction to nonperturbative calculations in light-front QEDOct 01 2010A nonperturbative method for the solution of quantum field theories is described in the context of quantum electrodynamics and applied to the calculation of the electron's anomalous magnetic moment. The method is based on light-front quantization and ... More
Experimental CMB Status and Prospects: A Report from Snowmass 2001Nov 29 2001In recent years the promise of experimental study of the cosmic microwave background (CMB) has been demonstrated. Herein a brief summary of the field is followed by an indication of future directions. The prospects for further revelations from the details ... More
Quantum relativistic Toda chain at root of unity: isospectrality, modified Q-operator and functional Bethe ansatzMay 15 2002We investigate an N-state spin model called quantum relativistic Toda chain and based on the unitary finite dimensional representations of the Weyl algebra with q being N-th primitive root of unity. Parameters of the finite dimensional representation ... More
J/Psi Production in Au-Au Collisions at sqrt(s_NN) = 200 GeV at the Relativistic Heavy Ion ColliderMay 27 2003Sep 06 2003First results on charm quarkonia production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The yield of J/Psi's measured in the PHENIX experiment via electron-positron decay pairs at mid-rapidity for Au-Au reactions ... More
UHE and EHE neutrino induced taus inside the EarthMay 20 2002Tau neutrinos interacting inside the Earth produce $\tau$ leptons which thereafter can decay inside the atmosphere. The propagation of extremely energetic \nut's and $\tau$'s through the Earth is studied by means of a detailed Monte Carlo simulation, ... More
A dressing of zero-range potentials and electron-molecule scattering problem at Ramsauer-Townsend minimumOct 07 2004A dressing technique is used to improve zero range potential (ZRP) model. We consider a Darboux transformation starting with a ZRP, the result of the "dressing" gives a potential with non-zero range that depends on a seed solution parameters. Concepts ... More
Absolute continuity and singularity of two probability measures on a filtered spaceFeb 04 2008Apr 06 2011Let $\mu$ and $\nu$ be fixed probability measures on a filtered space $(\Omega, {\cal F}, ({\cal F}_t)_{t\in {\bf R}^{+}})$. Denote by $\mu_T $ and $\nu_T $ (respectively, $\mu_{T-} $ and $\nu_{T-} $) the restrictions of the measures $\mu$ and $\nu$ on ... More
Gauge Invariant Quantization of Dissipative Systems of Charged Particles in Extended Phase SpaceNov 14 2005Recently, it is shown that the extended phase space formulation of quantum mechanics is a suitable technique for studying the quantum dissipative systems. Here, as a further application of this formalism, we consider a dissipative system of charged particles ... More
On the Ascoli property for locally convex spaces and topological groupsNov 09 2016Dec 03 2016We characterize Ascoli spaces by showing that a Tychonoff space $X$ is Ascoli iff the canonical map from the free locally convex space $L(X)$ over $X$ into $C_k\big( C_k(X)\big)$ is an embedding of locally convex spaces. We prove that an uncountable direct ... More
Disorder, History Dependence and Phase Transitions in a Flux LatticeAug 20 1997Aug 21 1997The vortex lattice is an ideal system to study the competition and interplay between interaction and disorder. New results on 2H-NbSe_2 (in samples of progressively increasing pinning) elucidate how pinning alters the phase boundary separating the "ordered" ... More
Phase separation in a polarized Fermi gas at zero temperatureOct 08 2007Dec 06 2007We investigate the phase diagram of asymmetric two-component Fermi gases at zero temperature as a function of polarization and interaction strength. The equations of state of the uniform superfluid and normal phase are determined using quantum Monte Carlo ... More
TraitsJul 11 2005Reminiscences about Alexandr Danilovich Alexandrov (1912--1999)
Microscopic Space-Time of Extended Hadrons : Quantum Generalization and Field EquationsAug 27 2003The microlocal space-time of extended hadrons, considered to be anisotropic is specified here as a special Finsler space. For this space the classical field equation is obtained from a property of the field on the neighbouring points of the autoparallel ... More
Pontryagin duality for Abelian $s$- and $sb$-groupsJan 14 2011The main goal of the article is to study the Pontryagin duality for Abelian $s$- and $sb$-groups. Let $G$ be an infinite Abelian group and $X$ be the dual group of the discrete group $G_d$. We show that a dense subgroup $H$ of $X$ is $\mathfrak{g}$-closed ... More
Abstract Convexity and Cone-Vexing AbstractionsMay 19 2007This talk is a write-up on some origins of abstract convexity and afew vexing limitations on the range of abstraction in convexity.
Interaction of Order and ConvexityMay 29 2007This is an overview of merging the techniques of Riesz space theory and convex geometry.
Nonstandard Analysis: Its Creator and PlaceJun 18 2013Jul 01 2013This is a biographical sketch and tribute to Abraham Robinson (1918-1974) on the 95th anniversary of his birth with a short discussion of the place of nonstandard analysis in the present-day mathematics.
Nonstandard Models and OptimizationMay 26 2008This is an overview of a few possibilities that are open by model theory in applied mathematics. Most attention is paid to the present state and frontiers of the Cauchy method of majorants, approximation of operator equations with finite-dimensional analogs, ... More
Multiple Criteria Problems over Minkowski BallsMar 22 2013Under study are some vector optimization problems over the space of Minkowski balls, i.e., symmetric convex compact subsets in Euclidean space. A typical problem requires to achieve the best result in the presence of conflicting goals; e.g., given the ... More
Minimally almost periodic group topology on countable torsion Abelian groupsJan 31 2010Feb 07 2010For any countable torsion subgroup $H$ of an unbounded Abelian group $G$ there is a complete Hausdorff group topology $\tau$ such that $H$ is the von Neumann radical of $(G,\tau)$. In particular, any unbounded torsion countable Abelian group admits a ... More
A characterization of free locally convex spaces over metrizable spaces which have countable tightnessJul 06 2014We prove that the free locally convex space $L(X)$ over a metrizable space $X$ has countable tightness if and only if $X$ is separable.
On the growth of the polynomial entropy integrals for the measures in the Szego classDec 22 2011For the polynomials orthogonal on the unit circle with respect to the measure from the Szego class we prove that the polynomial entropy integrals can grow. The estimate obtained is sharp.
Special invited paper. Large deviationsApr 15 2008This paper is based on Wald Lectures given at the annual meeting of the IMS in Minneapolis during August 2005. It is a survey of the theory of large deviations.
A description of several coordinate systems for hyperbolic spacesDec 19 2001This article simply presents several coordinate systems for 2 and 3-dimensional hyperbolic spaces, describing the general solutions of Helmholtz equation in each one of these systems.
Characterization of almost maximally almost-periodic groupsMar 08 2009Let $G$ be an abelian group. We prove that a group $G$ admits a Hausdorff group topology $\tau$ such that the von Neumann radical $\mathbf{n}(G, \tau)$ of $(G, \tau)$ is non-trivial and finite iff $G$ has a non-trivial finite subgroup. If $G$ is a topological ... More
Some families of graphs with no nonzero real domination rootsMar 12 2015Let G be a simple graph of order n. The domination polynomial is the generating polynomial for the number of dominating sets of G of each cardinality. A root of this polynomial is called a domination root of G. Obviously 0 is a domination root of every ... More
Domination polynomials of k-tree related graphsJul 22 2014Let $G$ be a simple graph of order $n$. The domination polynomial of $G$ is the polynomial $D(G, x)=\sum_{i=\gamma(G)}^{n} d(G,i) x^{i}$, where $d(G,i)$ is the number of dominating sets of $G$ of size $i$ and $\gamma(G)$ is the domination number of $G$. ... More
A scaling law for the cosmological constant from a stochastic model for cosmic structuresNov 30 2008May 12 2009A set of scaling laws, based on the stochastic motions of the granular components of astronomical systems, is applied to a cosmological model with a positive cosmological constant. It follows that the mass of the dominant particle in the observable universe ... More
Fractal large-scale structure from a stochastic scaling law modelMar 27 2009A stochastic model relating the parameters of astrophysical structures to the parameters of their granular components is applied to the formation of hierarchical, large-scale structures from galaxies assumed as point-like objects. If the density profile ... More
Interval decomposition lattices are balancedJun 24 2013Jun 27 2013Intervals in binary or n-ary relations or other discrete structures generalize the concept of interval in a linearly ordered set. Join-irreducible partitions into intervals are characterized in the lattice of all interval decompositions of a set, in a ... More
Explicit computation of the electrostatic energy for an elliptical charged discJan 06 2014This letter describes a method for obtaining an explicit expression for the electrostatic energy of a charged elliptical infinitely thin disc. The charge distribution is assumed to be polynomial. Such explicit values for this energy are fundamental for ... More
Quotient Equations and Integrals of Motion for Vector Massless FieldDec 14 2002In this article a group-theoretical aspect of the method of dimensional reduction is presented. Then, on the base of symmetry analysis of an anisotropic space geometrical description of dimensional reduction of equations for vector massless field is given. ... More
Soft-wall modelling of meson spectraApr 11 2016Apr 14 2016The holographic methods inspired by the gauge/gravity correspondence from string theory have been actively applied to the hadron spectroscopy in the last eleven years. Within the phenomenological bottom-up approach, the linear Regge-like trajectories ... More
Veneziano like amplitude as a test for AdS/QCD modelsNov 24 2011The high energy asymptotics of QCD correlation functions is often used as a test for bottom-up holographic models. Since QCD is not strongly coupled in the ultraviolet domain, such a test may look questionable. We propose that the sum over resonance poles ... More
A five-dimensional ansatz for the Veneziano amplitudeFeb 14 2011Jul 11 2012A hypothesis is put forward that in the case of low-energy QCD, the holographic prescription for calculating the correlation functions may lead to the dual scattering amplitudes of Veneziano type at zero momentum transfer if the non-conformality is properly ... More
Axial coupling from matching constituent quark model to QCDMay 19 2008The axial-vector coupling $g_A$ of a constituent quark is estimated from matching the constituent quark model to the operator product expansion in QCD in the limit of large number of colours under some assumptions. The obtained relation is $g_A\simeq\sqrt{7/11}\approx0.80$, ... More
A five-dimensional effective model for excited light mesonsJul 28 2010In the usual holographic approach to QCD, the meson spectrum is generated due to a non-trivial 5-dimensional background. We propose an alternative 5-dimensional scenario in which the spectrum emerges due to coupling to a scalar field whose condensation ... More
Hydrogen like classification for light nonstrange mesonsSep 27 2007Sep 09 2008The recent experimental results on the spectrum of highly excited light nonstrange mesons are known to reveal a high degree of degeneracy among different groups of states. We revise some suggestions about the nature of the phenomenon and put the relevant ... More
Light meson spectrum and classical symmetries of QCDJun 29 2006Jul 24 2006Modern spectroscopic data on light non-strange meson spectrum is analyzed. It is argued that the observed regularities of experimental spectrum for highly excited states favour a partial restoration of all approximate classical symmetries of QCD Lagrangian ... More
Relation between quark and gluon condensates from QCD sum rulesMar 22 2006A new relation between $\rho$-meson mass, weak $\pi$-meson decay constant, quark and gluon condensates is derived from the QCD sum rules. As a byproduct an explanation for the dominance of $\rho\rho$-decay for the $f_0(1370)$-meson is proposed.
Finite time analysis based on Sum of Squares Technique: Applied to the super-twisting second order sliding mode controlJun 08 2015Finite time analysis of the continuous system is investigated through both stability and stabilization based on Sum of squares programming. A systematic approach is proposed to construct Lyapunov function and Control Lyapunov function for this objective. ... More
Empirical Emission Functions for LPM Suppression of Photon Emission from Quark-Gluon PlasmaNov 06 2002The LPM suppression of photon emission rates from the quark gluon plasma have been studied at different physical conditions of the plasma given by temperature and chemical potentials.The integral equation for the transverse vector function (f(p_t)) consisting ... More
On the Variational method for LPM Suppression of Photon Emission from Quark-Gluon PlasmaAug 12 2002The photon emission rates from the quark gluon plasma have been studied considering LPM suppression effects. The integral equation for the transverse vector function (f(p)) that consists of multiple scattering effects has been solved using self-consistent ... More