Results for "A. Bonardi"

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Interagir avec un contenu opératique : le projet d'opéra virtuel interactif VirtualisDec 24 2009In this article, we present the interactive opera project on CD-ROM Virtualis. This project includes a scientific dimension as well as artistic. It gave us the opportunity to design a model of the opera performance using formalisms from organization sciences. ... More
Developments for coating, testing, and aligning Cherenkov Telescope Array mirrors in TübingenJul 19 2013The Cherenkov Telescope Array (CTA) is the next generation very-high energy gamma-ray air-shower Cherenkov observatory. CTA will consist of many segmented-mirror telescopes of three different diameters, placed in two arrays, one in the Northern hemisphere ... More
Recent developments for the testing of Cherenkov Telescope Array mirrors and actuators in TübingenAug 25 2015The Cherenkov Telescope Array (CTA) is the next generation Cherenkov telescope facility. It will consist of a large number of segmented-mirror telescopes of three different diameters, placed in two locations, one in the northern and one in the southern ... More
Status of the Lunar Detection Mode for Cosmic Particles of LOFARMar 20 2019Cosmic particles hitting Earth's moon produce radio emission via the Askaryan effect. If the resulting radio ns-pulse can be detected by radio telescopes, this technique potentially increases the available collective area for ZeV scale particles by several ... More
Cosmic Ray Physics with the LOFAR Radio TelescopeMar 20 2019The LOFAR radio telescope is able to measure the radio emission from cosmic ray induced air showers with hundreds of individual antennas. This allows for precision testing of the emission mechanisms for the radio signal as well as determination of the ... More
Performances and stability of a 2.4 ton Gd organic liquid scintillator target for antineutrino detectionMar 11 2008In this work we report the performances and the chemical and physical properties of a (2 x 1.2) ton organic liquid scintillator target doped with Gd up to ~0.1%, and the results of a 2 year long stability survey. In particular we have monitored the amount ... More
Measurement of the circular polarization in radio emission from extensive air showers confirms emission mechanismsNov 02 2016Nov 19 2016We report here on a novel analysis of the complete set of four Stokes parameters that uniquely determine the linear and/or circular polarization of the radio signal for an extensive air shower. The observed dependency of the circular polarization on azimuth ... More
Thunderstorm electric fields probed by extensive air showers through their polarized radio emissionMar 14 2017Mar 20 2017We observe a large fraction of circular polarization in radio emission from extensive air showers recorded during thunderstorms, much higher than in the emission from air showers measured during fair-weather circumstances. We show that the circular polarization ... More
Calibration of the LOFAR low-band antennas using the Galaxy and a model of the signal chainMar 14 2019The LOw-Frequency ARray (LOFAR) is used to make precise measurements of radio emission from extensive air showers, yielding information about the primary cosmic ray. Interpreting the measured data requires an absolute and frequency-dependent calibration ... More
First CNGS events detected by LVDOct 08 2007The CERN Neutrino to Gran Sasso (CNGS) project aims to produce a high energy, wide band $\nu_{\mu}$ beam at CERN and send it toward the INFN Gran Sasso National Laboratory (LNGS), 732 km away. Its main goal is the observation of the $\nu_{\tau}$ appearance, ... More
Similarité en intension vs en extension : à la croisée de l'informatique et du théâtreDec 24 2009Traditional staging is based on a formal approach of similarity leaning on dramaturgical ontologies and instanciation variations. Inspired by interactive data mining, that suggests different approaches, we give an overview of computer science and theater ... More
How Do Interactive Virtual Operas Shift Relationships between Music, Text and Image?Dec 24 2009In this paper we present the new genre of interactive operas implemented on personal computers. They differ from traditional ones not only because they are virtual, but mainly because they offer to composers and listeners new perspectives of combinations ... More
The Mirror Alignment and Control System for CT5 of the H.E.S.S. experimentSep 14 2015Oct 07 2015The High Energy Stereoscopic System (H.E.S.S.) experiment is one of the largest observatories for gamma-ray astronomy. It consists of four telescopes with a reflecting dish diameter of 12m (CT1 to CT4) and a newer large telescope (CT5) with a reflecting ... More
Music-ripping: des pratiques qui provoquent la musicologieDec 24 2009Out of the scope of the usual positions of computing in the field of music and musicology, one notices the emergence of human-computer systems that do exist by breaking off. Though these singular systems take effect in the usual fields of expansion of ... More
Central Acceptance Testing for Camera Technologies for CTAAug 25 2015The Cherenkov Telescope Array (CTA) is an international initiative to build the next generation ground based very-high energy gamma-ray observatory. It will consist of telescopes of three different sizes, employing several different technologies for the ... More
Mirror Development for the Cherenkov Telescope ArrayJul 17 2013The Cherenkov Telescope Array (CTA) is a planned observatory for very-high energy gamma-ray astronomy. It will consist of several tens of telescopes of different sizes, with a total mirror area of up to 10,000 square meters. Most mirrors of current installations ... More
Search for Cosmic Particles with the Moon and LOFARSep 21 2016The low flux of the ultra-high energy cosmic rays (UHECR) at the highest energies provides a challenge to answer the long standing question about their origin and nature. A significant increase in the number of detected UHECR is expected to be achieved ... More
The effect of the atmospheric refractive index on the radio signal of extensive air showersJan 25 2017For the interpretation of measurements of radio emission from extensive air showers, an important systematic uncertainty arises from natural variations of the atmospheric refractive index $n$. At a given altitude, the refractivity $N=10^6\, (n-1)$ can ... More
Realtime processing of LOFAR data for the detection of nano-second pulses from the MoonDec 20 2016The low flux of the ultra-high energy cosmic rays (UHECR) at the highest energies provides a challenge to answer the long standing question about their origin and nature. Even lower fluxes of neutrinos with energies above $10^{22}$ eV are predicted in ... More
A new solution for mirror coating in $γ$-ray Cherenkov AstronomyJun 03 2014In the $\gamma$-ray Cherenkov Astronomy framework mirror coating plays a crucial role in defining the light response of the telescope. We carried out a study for new mirror coating solutions with both a numerical simulation software and a vacuum chamber ... More
Measurement of the circular polarization in radio emission from extensive air showers confirms emission mechanismsNov 02 2016We report here on a novel analysis of the complete set of four Stokes parameters that uniquely determine the linear and/or circular polarization of the radio signal for an extensive air shower. The observed dependency of the circular polarization on azimuth ... More
On-line recognition of supernova neutrino bursts in the LVD detectorOct 01 2007In this paper we show the capabilities of the Large Volume Detector (INFN Gran Sasso National Laboratory) to identify a neutrino burst associated to a supernova explosion, in the absence of an "external trigger", e.g., an optical observation. We describe ... More
Status of the technologies for the production of the Cherenkov Telescope Array (CTA) mirrorsOct 07 2013The Cherenkov Telescope Array (CTA) is the next generation very high-energy gamma-ray observatory, with at least 10 times higher sensitivity than current instruments. CTA will comprise several tens of Imaging Atmospheric Cherenkov Telescopes (IACTs) operated ... More
Science with the Cherenkov Telescope ArraySep 23 2017Jan 22 2018The Cherenkov Telescope Array, CTA, will be the major global observatory for very high energy gamma-ray astronomy over the next decade and beyond. The scientific potential of CTA is extremely broad: from understanding the role of relativistic cosmic particles ... More
CTA contributions to the 33rd International Cosmic Ray Conference (ICRC2013)Jul 08 2013Jul 29 2013Compilation of CTA contributions to the proceedings of the 33rd International Cosmic Ray Conference (ICRC2013), which took place in 2-9 July, 2013, in Rio de Janeiro, Brazil
Cherenkov Telescope Array Contributions to the 35th International Cosmic Ray Conference (ICRC2017)Sep 11 2017Oct 24 2017List of contributions from the Cherenkov Telescope Array Consortium presented at the 35th International Cosmic Ray Conference, July 12-20 2017, Busan, Korea.
Contributions of the Cherenkov Telescope Array (CTA) to the 6th International Symposium on High-Energy Gamma-Ray Astronomy (Gamma 2016)Oct 17 2016List of contributions from the Cherenkov Telescope Array (CTA) Consortium presented at the 6th International Symposium on High-Energy Gamma-Ray Astronomy (Gamma 2016), July 11-15, 2016, in Heidelberg, Germany.
CTA Contributions to the 34th International Cosmic Ray Conference (ICRC2015)Aug 24 2015Sep 11 2015List of contributions from the CTA Consortium presented at the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands.
Renormalization of the Yang-Mills theory in the ambiguity-free gaugeFeb 12 2010Jul 27 2010The renormalization procedure for the Yang-Mills theory in the gauge free of the Gribov ambiguity is constructed. It is shown that all the ultraviolet infinities may be removed by renormalization of the parameters entering the classical Lagrangian and ... More
Programming Realization of Symbolic Computations for Non-linear Commutator Superalgebras over the Heisenberg--Weyl Superalgebra: Data Structures and Processing MethodsMay 16 2009Aug 19 2009We suggest a programming realization of an algorithm for verifying a given set of algebraic relations in the form of a supercommutator multiplication table for the Verma module, which is constructed according to a generalized Cartan procedure for a quadratic ... More
Nonreciprocal Photon Transmission and Amplification via Reservoir EngineeringFeb 25 2015Jun 05 2015We discuss a general method for constructing nonreciprocal, cavity-based photonic devices, based on matching a given coherent interaction with its corresponding dissipative counterpart; our method generalizes the basic structure used in the theory of ... More
Anomalous mass dimension of multi-flavor QCDOct 08 2016Models of strongly interacting theories with a large mass anomalous dimension ($\gamma_m$) provide an interesting possibility for the dynamical origin of the electroweak symmetry breaking. A laboratory for these models is QCD with many flavors, which ... More
A 125 GeV Scalar Boson and SU(N_{TC})\otimes SU(3)_{{}_{L}}\otimes U(1)_{{}_{X}} modelsMar 16 2013We verify that SU(N)_{{}_{TC}}\otimes SU(3)_{{}_{L}}\otimes U(1)_{{}_{X}} models, where the gauge symmetry breaking is totally dynamical and promoted by the non-Abelian technicolor (TC) group and the strong Abelian interactions, are quite constrained ... More
Mass and width of a composite Higgs bosonFeb 13 2009May 18 2009The scalar Higgs boson mass in a Technicolor model was obtained by Elias and Scadron with the analysis of an homogeneous Bethe-Salpeter equation (BSE), however it was performed before the most recent developments of walking gauge theories. It was not ... More
A dynamical mechanism to explain the top-bottom quark mass hierarchyAug 17 2004Jan 20 2005We discuss the mass splitting between the the top and bottom quarks in a technicolor scenario. The model proposed here contains a left-right electroweak gauge group. An extended technicolor group and mirror fermions are introduced. The top-bottom quark ... More
Entanglement swapping, light cones and elements of realityNov 06 2005Jul 20 2006Recently, a number of two-participant all-versus-nothing Bell experiments have been proposed. Here, we give local realistic explanations for these experiments. More precisely, we examine the scenario where a participant swaps his entanglement with two ... More
Jet radio emission in Cygnus X-1 and its orbital modulationOct 01 2006Dec 22 2006We present results of our detailed theoretical study of the observed orbital modulation of the radio emission in Cyg X-1. The modulation occurs due to free-free absorption in the wind from the companion star varying with the orbital phase, and our results ... More
Geodesics and admissible-path spaces in Carnot GroupsNov 26 2013We study the topology of admissible-loop spaces on a step-two Carnot group G. We use a Morse-Bott theory argument to study the structure and the number of geodesics on G connecting the origin with a 'vertical' point (geodesics are critical points of the ... More
Periodic solutions of Schrodinger equation in Hilbert spaceSep 03 2012Necessary and sufficient conditions for existence of boundary value problem of Schrodinger equation are obtained in linear and nonlinear cases. Periodic analytical solutions are represented using generalized Green's operator
Numerical analysis of renormalon technique in quantum mechanicsNov 29 1996Jul 14 1997We discuss the ways of extracting a low energy scale of an underlying theory using high energy scattering data. Within an exactly solvable model of quantum mechanics we analyze a technique based on introduction of nonperturbative power corrections accounting ... More
Analytical results for $e^+e^-\to t\bar t$ and $γγ\to t\bar t$ observables near the threshold up to the next-to-next-to-leading order of NRQCDApr 08 1999Oct 10 2001We present an analytical description of top-antitop pair production near the threshold in $e^+e^-$ annihilation and $\g\g$ collisions. A set of basic observables considered includes the total cross sections, forward-backward asymmetry and top quark polarization. ... More
Next-to-next-to-leading order relation between $R(e^+e^-\to b\bar b)$ and $Γ_{\rm sl}(b\to clν_l)$ and precise determination of $|V_{cb}|$May 16 1998Oct 30 1998We present the next-to-next-to-leading order relation between the moments of the $\Upsilon$ system spectral density and the inclusive $B$-meson semileptonic width. The perturbative series for the width as an explicit function of the moments is well convergent ... More
Quark-hadron duality for $K^0-\bar{K^0}$ mixingNov 27 1997Long distance contribution to the $K^0-\bar K^0$ mixing is taken into account consistently and the corrections to the naive duality result represented by the famous box diagram are found to be small. Estimates are given in the leading order of the chiral ... More
A scalar gluonium contribution to $K\rightarrowππ$ decayJul 17 1995We study a new $K\rightarrow\pi\pi$ decay channel with gluons in intermediate state which is normally neglected within the factorization framework. Both short-distance and long-distance parts of the amplitude are calculated. The chiral Lagrangian approach ... More
Effects of the stellar wind on X-ray spectra of Cygnus X-3Oct 30 2007Feb 04 2008We study X-ray spectra of Cyg X-3 from BeppoSAX, taking into account absorption and emission in the strong stellar wind of its companion. We find the intrinsic X-ray spectra are well modelled by disc blackbody emission, its upscattering by hot electrons ... More
On open superstring partition function in inhomogeneous rolling tachyon backgroundOct 27 2003Jan 27 2004We consider open superstring partition function Z on the disc in time-dependent tachyon background T= f(x_i) e^{m x_0} where the profile function f depends on spatial coordinates. We compute Z to second order in derivatives of f and compare the result ... More
On gravitational couplings in D-brane actionNov 12 2002Oct 26 2004We compute the two closed string graviton - two open string scalar scattering amplitude on the disc to show that there is no second-derivative curvature - scalar coupling term R X^2 in the low-energy effective action of a D-brane in curved space in type ... More
Coherent effects in double-barrier Josephson junctionsDec 07 1999The general solution for ballistic electronic transport through double-barrier Josephson junctions is derived. We show the existence of a regime of phase-coherent transport in which the supercurrent is proportional to the single barrier transparency and ... More
The origin of the first and third generation fermion masses in a technicolor scenarioFeb 19 2003Jan 22 2004We argue that the masses of the first and third fermionic generations, which are respectively of the order of a few MeV up to a hundred GeV, are originated in a dynamical symmetry breaking mechanism leading to masses of the order $\alpha \mu$, where $\alpha$ ... More
On (non)integrability of classical strings in p-brane backgroundsNov 15 2012Jan 07 2013We investigate the question of possible integrability of classical string motion in curved p-brane backgrounds. For example, the D3-brane metric interpolates between the flat and the AdS_5 x S^5 regions in which string propagation is integrable. We find ... More
On the power of non-local boxesApr 18 2005Nov 07 2005A non-local box is a virtual device that has the following property: given that Alice inputs a bit at her end of the device and that Bob does likewise, it produces two bits, one at Alice's end and one at Bob's end, such that the XOR of the outputs is ... More
Casimir effect for scalar fields under Robin boundary conditions on platesJul 31 2000Oct 22 2001We study the Casimir effect for scalar fields with general curvature coupling subject to mixed boundary conditions $(1+\beta_{m}n^{\mu}\partial_{\mu})\phi =0$ at $x=a_{m}$ on one ($m=1$) and two ($m=1,2$) parallel plates at a distance $a\equiv a_{2}-a_{1}$ ... More
Technicolor models with coupled systems of Schwinger-Dyson equationsFeb 28 2019When Technicolor (TC), QCD, Extended Technicolor (ETC) and other interactions become coupled through their different Schwinger-Dyson equations, the solution of these equations are modified in comparison with the ones of the isolated equations. The change ... More
A statistical model of three-dimensional anisotropy and intermittency in strong Alfvénic turbulenceMay 24 2016Dec 14 2016We propose a simple statistical model of three-dimensionally anisotropic, intermittent, strong Alfv\'enic turbulence, incorporating both critical balance and dynamic alignment. Our model is based on log-Poisson statistics for Elsasser-field increments ... More
Exact string background from a WZW model based on the Heisenberg groupMar 07 1994A WZW model for the non-semi-simple D-dimensional Heisenberg group, which directly generalizes the E_{2}^{c} group, is constructed. It is found to correspond to an D-dimensional string background of plane-wave type with physical Lorentz signature D-2. ... More
Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for $b \bar b$ systemMar 16 1998Apr 06 1998A correlator of the vector current of a heavy quark is computed analytically near threshold in the next-to-next-to-leading order in perturbative and relativistic expansion that includes $\al_s^2$, $\al_sv$ and $v^2$ corrections in the coupling constant ... More
Comment on ``Next-to-next-to-leading order vacuum polarization function of heavy quark near threshold and sum rules for $b \bar b$ system'' and ``Next-to-next-to-leading order relation between $R(e^+e^-\to b\bar b)$ and $Γ_{\rm sl}(b\to clν_l)$ and precise ... MoreJan 19 1999The most recent recalculation of the two-loop correction to the static quark-antiquark potential gave the numerical value different from the previously known one. We comment on the effect this change produces on the numerical estimates of the bottom quark ... More
Extended analysis of the "penguin" part of $K\toππ$ amplitudeMar 14 1995We make an attempt to clarify the role of the annihilation or "penguin" mode in the description of the $K\rightarrow\pi\pi$ decay within the Standard Model. The attention is concentrated on new operators in the effective $\Delta S=1$ Hamiltonian and the ... More
Ambiguity-free formulation of the Higgs-Kibble modelOct 05 2010A renormalizable ambiguity-free formulation of the Higgs-Kibble model is proposed.
Quantum-Limited Amplification via Reservoir EngineeringNov 01 2013Apr 08 2014We describe a new kind of phase-preserving quantum amplifier which utilizes dissipative interactions in a parametrically-coupled three-mode bosonic system. The use of dissipative interactions provides a fundamental advantage over standard cavity-based ... More
Crossed Andreev reflection in diffusive contactsNov 06 2006Crossed Andreev reflection in multiterminal structures in the diffusive regime is addressed within the quasiclassical Keldysh-Usadel formalism. The elastic cotunneling and crossed Andreev reflection of quasiparticles give nonlocal currents and voltages ... More
Light composite scalar boson from a see-saw mechanism in two-scale TC modelsJun 25 2015We consider the possibility of a light composite scalar boson arising from mass mixing between a relatively light and heavy scalar singlets in a see-saw mechanism expected to occur in two-scale Technicolor (TC) models. A light composite scalar boson can ... More
Limit on the fermion masses in technicolor modelsAug 21 2003Recently it has been pointed out that no limits can be put on the scale of fermion mass generation $(M)$ in technicolor models, because the relation between the fermion masses $(m_f)$ and $M$ depends on the dimensionality of the interaction responsible ... More
Dynamical Symmetry Breaking in a Minimal 3-3-1 ModelOct 11 2012The gauge symmetry breaking in some versions of 3-3-1 models can be implemented dynamically because at the scale of a few TeVs the $U(1)_X$ coupling constant becomes strong. In this work we consider the dynamical symmetry breaking in a minimal $SU(3)_{{}_{TC}}\times ... More
Energy criterion to select the behavior of dynamical masses in technicolor modelsMay 05 2002We propose a quite general ansatz for the dynamical mass in technicolor models. We impose on this ansatz the condition for formation of the tightest composite boson state, or the criterion that it should lead to the deepest minimum of energy. This criterion ... More
Quantum corrections to energy of short spinning string in AdS5Jun 29 2008Feb 02 2009Motivated by desire to shed light on the strong coupling behaviour of anomalous dimensions of "short" gauge theory operators we consider the famous example of folded spinning string in AdS_5 in the limit of small semiclassical spin parameter \S = S/sqrt[lambda]. ... More
A statistical model of three-dimensional anisotropy and intermittency in strong Alfvénic turbulenceMay 24 2016We propose a simple statistical model of three-dimensionally anisotropic, intermittent, strong Alfv\'enic turbulence, incorporating both critical balance and dynamic alignment. Our model is based on log-Poisson statistics for Elsasser-field increments ... More
One- and many-body effects on mirages in quantum corralsAug 27 2002May 23 2003Recent interesting experiments used scanning tunneling microscopy to study systems involving Kondo impurities in quantum corrals assembled on Cu or noble metal surfaces. The solution of the two-dimensional one-particle Schrodinger equation in a hard wall ... More
New results for the missing quantum numbers labeling the quadrupole and octupole boson basisMay 24 2004Oct 27 2004The many $2^k$-pole boson states, $|N_kv_k\alpha_k I_kM_k>$ with $k=2,3$, realize the irreducible representation (IR) for the group reduction chains $SU(2k+1)\supset R_{2k+1}\supset R_3\supset R_2$. They have been analytically studied and widely used ... More
Thin topological insulator film in a perpendicular magnetic fieldMar 10 2011May 10 2011We report on a study of an ultrathin topological insulator film with hybridization between the top and bottom surfaces, placed in a quantizing perpendicular magnetic field. We calculate the full Landau level spectrum of the film as a function of the applied ... More
Bottom quark pole mass and $|V_{cb}|$ matrix element from $R(e^+e^-\to b\bar b)$ and $Γ_{sl}(b\to clν_l)$ in the next-to-next-to-leading orderJul 20 1998Mar 19 1999We present a consistent analysis of $\Upsilon$ sum rules and $B$-meson semileptonic width in the next-to-next-to-leading order in the strong coupling constant. The analysis is based on the analytical result for the heavy quark vector current correlator ... More
Practical techniques of QCD vs exact results of solvable modelsDec 30 1996Jul 14 1997We check quantitatively the validity of some popular phenomenological approaches of QCD in simple models. Dispersion sum rules are considered within the ladder approximation of a field-theoretic model with OPE given by ordinary loop diagrams which are ... More
Anomalous diffusion and quasistationarity in the HMF modelNov 12 2007We explore the quasistationary regime of the Hamiltonian Mean Field Model (HMF) showing that at least three different classes of events exist, with a different diffusive behavior and with a relative frequency which depends on the size of the system. Along ... More
Broadband polarization retarderApr 26 2011We derive a new kind of effective broadband polarization device using the analogy between the equation for the polarization of light, propagating through an optically anisotropic medium, and the optical Bloch equation in adiabatic regime, which describes ... More
Sigma model approach to string theory effective actions with tachyonsNov 06 2000Mar 04 2001Motivated by recent discussions of actions for tachyon and vector fields related to tachyon condensation in open string theory we review and clarify some aspects of their derivation within sigma model approach. In particular, we demonstrate that the renormalized ... More
On field redefinitions and exact solutions in string theoryAug 09 1993Sep 15 1993String backgrounds associated with gauged $G/H$ WZNW models in general depend non-trivially on $\alpha'$. We note, however, that there exists a local covariant $\a'$-dependent field redefinition that relates the exact metric-dilaton background corresponding ... More
Open superstring partition function in constant gauge field background at finite temperatureFeb 19 1998Mar 06 1998We find the general expression for the open superstring partition function on the annulus in a constant abelian gauge field background and at finite temperature. We use the approach based on Green-Schwarz string path integral in the light-cone gauge and ... More
On SO(32) heterotic - type I superstring duality in ten dimensionsOct 24 1995Nov 15 1995We provide some additional evidence in favour of the strong - weak coupling duality between the SO(32) heterotic and type I superstring theories by comparing terms quartic in the gauge field strength in their low-energy effective actions. We argue that ... More
Closed superstrings in magnetic field: instabilities and supersymmetry breakingOct 07 1995Oct 08 1995We consider a 2-parameter class of solvable closed superstring models which `interpolate' between Kaluza-Klein and dilatonic Melvin magnetic flux tube backgrounds. The spectrum of string states has similarities with Landau spectrum for a charged particle ... More
String solutions with non-constant scalar fieldsFeb 14 1994We discuss charged string solutions of the effective equations of D=4 heterotic string theory with non-constant dilaton and modulus fields. The effective action contains a generic moduli-dependent coupling function in the gauge field kinetic term and ... More
On sigma model RG flow, "central charge" action and Perelman's entropyDec 29 2006Jan 24 2007Zamolodchikov's c-theorem type argument (and also string theory effective action constructions) imply that the RG flow in 2d sigma model should be gradient one to all loop orders. However, the monotonicity of the flow of the target-space metric is not ... More
The liquid Argon TPC: a powerful detector for future neutrino experiments and proton decay searchesSep 02 2005We discuss the possibility of new generation neutrino and astroparticle physics experiments exploiting the liquid Argon Time Projection Chamber (LAr TPC) technique, following a graded strategy that envisions applications with increasing detector masses ... More
Lattice QCD with Exponentially Small Chirality BreakingJul 30 1998A new multifermion formulation of lattice QCD is proposed. The model is free of spectrum doubling and preserves all nonanomalous chiral symmetries up to exponentially small corrections. It is argued that a small number of fermion fields may provide a ... More
New approach to the quantization of the Yang-Mills fieldMar 11 2015Mar 12 2015Review of the papers on the new method of the Yang-Mills field quantization applicable both in perturbation theory and beyond it is presented. It is shown that in the modified formulation of the Yang-Mills theory leading to the formal perturbation theory, ... More
The Yang-Mills theory as a massless limit of a massive nonabelian gauge modelDec 13 2012A gauge invariant infrared regularization of the Yang-Mills theory applicable beyond perturbation theory is constructed.
Covariant formulation of non-Abelian gauge theories without anticommuting variablesOct 04 1999A manifestly Lorentz invariant effective action for Yang-Mills theory depending only on commuting fields is constructed. This action posesses a bosonic symmetry, which plays a role analogous to the BRST symmetry in the standard formalism.
Bosonization of Fermion DeterminantsJul 27 1995A four dimensional fermion determinant is presented as a path integral of the exponent of a local five dimensional action describing constrained bosonic system. The construction is carried out both in the continuum theory and in the lattice model.
Dmitrij Volkov, super-Poincare group and Grassmann variablesNov 03 2009Mar 03 2010A fundamental role of the Hermann Grassmann anticommuting variables both in physics and mathematics is discussed on the example of supersymmetry. The talk describes how the D. Volkov question about possibility of the existence of Nambu-Goldstone fermions, ... More
A simple model for high-energy nucleon-nucleon elastic diffraction and exclusive diffractive electroproduction of vector mesons on protonsDec 07 2010Aug 31 2011The processes of exclusive diffractive scattering $p+p\to p+p$, $\bar p+p\to\bar p+p$, and $\gamma^*+p\to V+p$ at high energies are considered in the framework of a unified Regge-eikonal model with a very simple reggeon structure of the eikonal. It is ... More
Non-Abelian Confinement via Abelian Flux Tubes in Softly Broken N=2 SUSY QCDFeb 25 2002Jun 28 2002We study confinement in softly broken N=2 SUSY QCD with gauge group SU(N_c) and N_f hypermultiplets of fundamental matter (quarks) when the Coulomb branch is lifted by small mass of adjoint matter. Concentrating mostly on the theory with SU(3) gauge group ... More
Weak Coupling Phase Structureof the Abelian Higgs Model at Finite TemperatureMay 03 1993Using the 1-loop reduced 3D action of the Abelian Higgs-model we discuss the order of its finite temperature phase transition. A two-variable saddle point approximation is proposed for the evaluation of the effective potential. The strength of the first ... More
One-loop derivation of the Wilson polygon - MHV amplitude dualityApr 02 2009We discuss the origin of the Wilson polygon - MHV amplitude duality at the perturbative level. It is shown that the duality for the MHV amplitudes at one-loop level can be proven upon the peculiar change of variables in Feynman parametrization and the ... More
Towards effective topological gauge theories on spectral curvesOct 30 1995Jan 22 1996We discuss a general approach to the nonperturbative treatment of quantum field theories based on existence of effective gauge theory on auxiliary ''spectral" Riemann curve. We propose an effective formulation for the exact solutions to some examples ... More
Symmetries and Consistency Relations in the Large Scale Structure of the UniverseFeb 01 2013Mar 31 2014We study the symmetries enjoyed by the Newtonian equations of motion of the non-relativistic dark matter fluid coupled to gravity which give rise to the phenomenon of gravitational instability. We also discuss some consistency relations involving the ... More
All WZW Mooels in $D\leq5$Jun 21 1994We present here all the real algebras $\cal{A}$ with dim$\cal{A}\leq $5 and all 6-dimensional nilpotent ones with symmetric, invariant and non-degenerate metrics for which a WZW model can be constructed. In three and four dimensions there are no other ... More
Power Spectrum Normalisation and the Non-Gaussian Halo ModelOct 14 2003The normalisation of the matter power spectrum, sigma_8, is an essential ingredient to predict the phenomenology of the low redshift universe. It has been measured using several methods, such as X-ray cluster counts, weak lensing and the cosmic microwave ... More
Why study pulsars optically?Aug 30 2002Observations of the five confirmed optical pulsars indicate that the peak emission scales according to the magnetic field strength at the light cylinder. To the accuracy that such low number allows we show that this gives further confirmation that a straightforward ... More
Weinstein -- Xu invariants and link group representationsApr 27 1994Jun 21 1994Topological interpretation of the link invariants associated with the Weinstein--Xu classical solutions of the quantum Yang-Baxter equation are provided.
Mechanical unfolding and refolding pathways of ubiquitinMar 10 2008Apr 22 2008Mechanical unfolding and refolding of ubiquitin are studied by Monte Carlo simulations of a Go model with binary variables. The exponential dependence of the time constants on the force is verified, and folding and unfolding lengths are computed, with ... More