Results for "B. Vlastakis"

total 80692took 0.10s
Calibration of the cross-resonance two-qubit gate between directly-coupled transmonsMay 14 2019Quantum computation requires the precise control of the evolution of a quantum system, typically through application of discrete quantum logic gates on a set of qubits. Here, we use the cross-resonance interaction to implement a gate between two superconducting ... More
Single-photon Resolved Cross-Kerr Interaction for Autonomous Stabilization of Photon-number StatesApr 13 2015Quantum states can be stabilized in the presence of intrinsic and environmental losses by either applying active feedback conditioned on an ancillary system or through reservoir engineering. Reservoir engineering maintains a desired quantum state through ... More
Implementing and characterizing precise multi-qubit measurementsJun 02 2016Jun 07 2016There are two general requirements to harness the computational power of quantum mechanics: the ability to manipulate the evolution of an isolated system and the ability to faithfully extract information from it. Quantum error correction and simulation ... More
Tracking Photon Jumps with Repeated Quantum Non-Demolition Parity MeasurementsNov 11 2013Quantum error correction (QEC) is required for a practical quantum computer because of the fragile nature of quantum information. In QEC, information is redundantly stored in a large Hilbert space and one or more observables must be monitored to reveal ... More
Hardware-efficient autonomous quantum error correctionJul 03 2012Jan 16 2013We propose a new method to autonomously correct for errors of a logical qubit induced by energy relaxation. This scheme encodes the logical qubit as a multi-component superposition of coherent states in a harmonic oscillator, more specifically a cavity ... More
Deterministic protocol for mapping a qubit to coherent state superpositions in a cavityMay 10 2012We introduce a new gate that transfers an arbitrary state of a qubit into a superposition of two quasi-orthogonal coherent states of a cavity mode, with opposite phases. This qcMAP gate is based on conditional qubit and cavity operations exploiting the ... More
Cavity State Manipulation Using Photon-Number Selective Phase GatesMar 04 2015The large available Hilbert space and high coherence of cavity resonators makes these systems an interesting resource for storing encoded quantum bits. To perform a quantum gate on this encoded information, however, complex nonlinear operations must be ... More
Black-box superconducting circuit quantizationApr 03 2012We present a semi-classical method for determining the effective low-energy quantum Hamiltonian of weakly anharmonic superconducting circuits containing mesoscopic Josephson junctions coupled to electromagnetic environments made of an arbitrary combination ... More
Universal Control of an Oscillator with Dispersive Coupling to a QubitFeb 27 2015Mar 12 2015We investigate quantum control of an oscillator mode off-resonantly coupled to an ancillary qubit. In the strong dispersive regime, we may drive the qubit conditioned on number states of the oscillator, which together with displacement operations can ... More
Observation of quantum state collapse and revival due to the single-photon Kerr effectNov 09 2012Photons are ideal carriers for quantum information as they can have a long coherence time and can be transmitted over long distances. These properties are a consequence of their weak interactions within a nearly linear medium. To create and manipulate ... More
Violating Bell's inequality with an artificial atom and a cat state in a cavityApr 09 2015The `Schr\"odinger's cat' thought experiment highlights the counterintuitive facet of quantum theory that entanglement can exist between microscopic and macroscopic systems, producing a superposition of distinguishable states like the fictitious cat that ... More
Demonstrating Quantum Error Correction that Extends the Lifetime of Quantum InformationFeb 15 2016The remarkable discovery of Quantum Error Correction (QEC), which can overcome the errors experienced by a bit of quantum information (qubit), was a critical advance that gives hope for eventually realizing practical quantum computers. In principle, a ... More
Confining the state of light to a quantum manifold by engineered two-photon lossDec 15 2014Physical systems usually exhibit quantum behavior, such as superpositions and entanglement, only when they are sufficiently decoupled from a lossy environment. Paradoxically, a specially engineered interaction with the environment can become a resource ... More
Power spectrum of electron number density perturbations at cosmological recombination epochDec 12 2008Feb 19 2009The power spectrum of number density perturbations of free electrons is obtained for the epoch of cosmological recombination of hydrogen. It is shown that amplitude of the electron perturbations power spectrum of scales larger than acoustic horizon exceeds ... More
Energy dependence of particle multiplicities in central Au+Au collisionsAug 08 2001We present the first measurement of the pseudorapidity density of primary charged particles in Au+Au collisions at sqrt(s_NN) = 200GeV. For the 6% most central collisions, we obtain dN_ch/deta|_|eta|<1 = 650 +/- 35 (syst). Compared to collisions at sqrt(s_NN) ... More
Transverse Momentum and Rapidity Dependence of HBT Correlations in Au+Au Collisions at sqrt(s_NN) = 62.4 and 200 GeVSep 01 2004Two-particle correlations of identical charged pion pairs from Au+Au collisions at sqrt(s_NN) = 62.4 and 200 GeV were measured by the PHOBOS experiment at RHIC. Data for the 15% most central events were analyzed with Bertsch-Pratt and Yano-Koonin-Podgoretskii ... More
Dirichlet boundary conditions in type IIB superstring theory and fermionic T-dualityFeb 01 2012Jul 02 2012In this article we investigate the relation between consequences of Dirichlet boundary conditions (momenta noncommutativity and parameters of the effective theory) and background fields of fermionic T-dual theory. We impose Dirichlet boundary conditions ... More
Noncommutativity relations in type IIB theory and their supersymmetryMay 07 2010In the present paper we investigate noncommutativity of $D9$ and $D5$-brane world-volumes embedded in space-time of type IIB superstring theory. Boundary conditions, which preserve half of the initial supersymmetry, are treated as canonical constraints. ... More
Noncommutativity in space-time extended by Liouville fieldNov 28 2007Oct 09 2009The world-sheet quantum conformal invariance can be realized in the presence of the conformal factor $F$, by inclusion of Liouville term. In the background with linear dilaton field, $\Phi(x)=\Phi_0+a_\mu x^\mu$, the field $F$ becomes a new noncommutative ... More
The Magnus property for direct productsMay 05 2016Jun 14 2016A group G is said to have the Magnus property if the following holds: whenever two elements x,y have the same normal closure, then x is conjugate to y or its inverse. We prove: Let p be an odd prime, and let G,H be residually finite-p groups with the ... More
Certain Topics on the Lie Algebra gl(lambda) Representation TheoryMar 15 1997The Lie algebra gl(lambda) dependent on the complex parameter lambda is a continuous version of the Lie algebra gl(inf) of infinite matrices with only finite number of nonzero entries. The gl(lambda) was first introduced by B.L.Feigin in [1] in connection ... More
Consequences of energy conservation in relativistic heavy-ion collisionsAug 15 2005Complete characterization of particle production and emission in relativistic heavy-ion collisions is in general not feasible experimentally. This work demonstrates, however, that the availability of essentially complete pseudorapidity distributions for ... More
Studies of multiplicity in relativistic heavy-ion collisionsNov 08 2004Nov 29 2004In this talk I'll review the present status of charged particle multiplicity measurements from heavy-ion collisions. The characteristic features of multiplicity distributions obtained in Au+Au collisions will be discussed in terms of collision centrality ... More
Pseudorapidity Distribution of Charged Particles in d + Au Collisions at $\sqrt{s_{_{NN}}$ = 200 GeVNov 10 2003The measured pseudorapidity distribution of primary charged particles in minimum-bias d + Au collisions at ${\sqrt{s_{_{NN}}} = \rm {200 GeV}}$ is presented for the first time. This distribution falls off less rapidly in the gold direction as compared ... More
The Radioactive Beam Program at ArgonneJun 06 2006In this talk I will present selected topics of the ongoing radioactive beam program at Argonne and discuss the capabilities of the CARIBU radioactive ion production facility as well as plans for construction of a novel superconducting solenoid spectrometer. ... More
Ratios of charged antiparticles to particles near mid-rapidity in Au+Au collisions at sqrt(s_NN) = 130 GeVApr 18 2001We have measured the ratios of antiparticles to particles for charged pions, kaons and protons near mid-rapidity in central Au+Au collisions at sqrt(s_NN) = 130 GeV. For protons, we observe pbar/p = 0.60 +/- 0.04 (stat.) +/- 0.06 (syst.) in the transverse ... More
Towards a strong-coupling theory of QCD at finite densitySep 02 2002We apply strong-coupling perturbation theory to the QCD lattice Hamiltonian. We begin with naive, nearest-neighbor fermions and subsequently break the doubling symmetry with next-nearest-neighbor terms. The effective Hamiltonian is that of an antiferromagnet ... More
Blandford's Argument: The Strongest Continuous Gravitational Wave SignalApr 18 2008Aug 18 2008For a uniform population of neutron stars whose spin-down is dominated by the emission of gravitational radiation, an old argument of Blandford states that the expected gravitational-wave amplitude of the nearest source is independent of the deformation ... More
Time Evolution of the Spread of Diseases with a General Infectivity Profile on a Complex Dynamic NetworkMay 21 2010This manuscript introduces a new analytical approach for studying the time evolution of disease spread on a finite size network. Our methodology can accommodate any disease with a general infectivity profile. This new approach is able to incorporate the ... More
Geometrically thin accretion disk around Maclaurin spheroidNov 22 2014We investigated a semi-analytic and numerical model to study the geometrically thin and optically thick accretion disk around Maclaurin spheroid (MS). The main interest is in the inner region of the so called {\alpha}-disk, {\alpha} being the viscosity ... More
A Search for Gamma-Ray Bursts and Pulsars, and the Application of Kalman Filters to Gamma-Ray ReconstructionFeb 04 2002Part I describes the analysis of periodic and transient signals in EGRET data. A method to search for the transient flux from gamma-ray bursts independent of triggers from other gamma-ray instruments is developed. Several known gamma-ray bursts were independently ... More
Four-point correlator constraints on electromagnetic chiral parameters and resonance effective LagrangiansMay 21 2004Jun 01 2004We pursue the analysis of a set of generalized DGMLY sum rules for the electromagnetic chiral parameters at order $e^2p^2$ and discuss implications for effective Lagrangians with resonances. We exploit a formalism in which charge spurions are introduced ... More
Electromagnetic corrections in the anomaly sectorMay 21 2002Chiral perturbation theory in the anomaly sector for $N_f=2$ is extended to include dynamical photons, thereby allowing a complete treatment of isospin breaking. A minimal set of independent chiral lagrangian terms is determined and the divergence structure ... More
Breaking and restoring of diffeomorphism symmetry in discrete gravitySep 30 2009We discuss the fate of diffeomorphism symmetry in discrete gravity. Diffeomorphism symmetry is typically broken by the discretization. This has repercussions for the observable content and the canonical formulation of the theory. It might however be possible ... More
Centrality dependence of charged antiparticle to particle ratios near mid-rapidity in d+Au collisions at sqrt(s_NN)=200 GeVSep 17 2003The ratios of the yields of charged antiparticles to particles have been obtained for pions, kaons, and protons near mid-rapidity for d+Au collisions at sqrt(s_NN) = 200 GeV as a function of centrality. The reported values represent the ratio of the yields ... More
Centrality dependence of charged hadron transverse momentum spectra in d+Au collisions at sqrt(s_NN) = 200 GeVJun 18 2003We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt(s_NN) = 200 GeV. The spectra were obtained for transverse momenta 0.25 < p_T < 6.0 GeV/c, in a pseudorapidity range of 0.2 < eta < 1.4 in the deuteron ... More
Scaling Variable for Nuclear Shadowing in Deep-Inelastic ScatteringSep 22 1995A new scaling variable is introduced in terms of which nuclear shadowing in deep-inelastic scattering is universal, i.e. independent of $A$, $Q^2$ and $x$. This variable can be interpreted as a measure of the number of gluons probed by the hadronic fluctuations ... More
Type I background fields in terms of type IIB onesApr 16 2008We choose such boundary conditions for open IIB superstring theory which preserve N=1 SUSY. The explicite solution of the boundary conditions yields effective theory which is symmetric under world-sheet parity transformation $\Omega:\sigma\to-\sigma$. ... More
Gauge symmetries decrease the number of Dp-brane dimensionsApr 19 2006Aug 09 2006It is known that the presence of antisymmetric background field $B_{\mu\nu}$ leads to noncommutativity of Dp-brane manifold. Addition of the linear dilaton field in the form $\Phi(x)=\Phi_0+a_\mu x^\mu$, causes the appearance of the commutative Dp-brane ... More
Continuum Lowering -- A New PerspectiveSep 05 2013Apr 23 2014What is meant by continuum lowering and ionization potential depression (IPD) in a Coulomb system depends upon precisely what question is being asked. It is shown that equilibrium (equation-of-state) phenomena and non-equilibrium dynamical processes like ... More
Gauge symmetries decrease the number of Dp-brane dimensions. II. Inclusion of the Liouville termNov 17 2006Apr 26 2007The presence of the antisymmetric background field $B_{\mu\nu}$ leads to the noncommutativity of the Dp-brane manifold, while the linear dilaton field in the form $\Phi(x)=\Phi_0+a_\mu x^\mu$, causes the appearance of the commutative Dp-brane coordinate, ... More
Inclusive Charmed-Baryon Decays and LifetimesApr 30 1997Jul 11 1997We have quantitatively reanalyzed the inclusive charmed-baryon decays. New ingredients are the Voloshin preasymptotic effects in semileptonic decays and the Cabibbo-subleading contributions to both semileptonic and nonleptonic decays. It has been found ... More
Open strings in relativistic ion trapsFeb 20 2003Apr 04 2003Electromagnetic plane waves provide examples of time-dependent open string backgrounds free of $\alpha'$ corrections. The solvable case of open strings in a quadrupolar wave front, analogous to pp-waves for closed strings, is discussed. In light-cone ... More
Charged Particle Multiplicities in Ultra-relativistic Au+Au and Cu+Cu CollisionsApr 26 2006The PHOBOS collaboration has carried out a systematic study of charged particle multiplicities in Cu+Cu and Au+Au collisions at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory. A unique feature of the PHOBOS detector is its ... More
The significance of the fragmentation region in ultrarelativistic heavy ion collisionsOct 09 2002We present measurements of the pseudorapidity distribution of primary charged particles produced in Au+Au collisions at three energies, sqrt(s_{NN}) = 19.6, 130, and 200 GeV, for a range of collision centralities. The centrality dependence is shown to ... More
Uniform semiclassical expansions for the direct part of Franck-Condon transitionsOct 13 1997Semiclassical expansions for traces involving Greens functions have two contributions, one from the periodic or recurrent orbits of the classical system and one from the phase space volume, i.e. the paths of infinitesimal length. Quantitative calculations ... More
RF depolarizing resonances in the presence of a full Siberian snake and full snake spin-flippingApr 18 2003Frequent polarization reversals, or spin-flips, of a stored polarized beam in a high energy scattering asymmetry experiments may greatly reduce systematic errors of spin asymmetry measurements. A spin-flipping technique is being developed by using rf ... More
Lower estimates of transition densities and bounds on exponential ergodicity for stochastic PDE'sFeb 18 2004Sep 25 2006A formula for the transition density of a Markov process defined by an infinite-dimensional stochastic equation is given in terms of the Ornstein--Uhlenbeck bridge and a useful lower estimate on the density is provided. As a consequence, uniform exponential ... More
Content based video retrieval systemsMay 08 2012With the development of multimedia data types and available bandwidth there is huge demand of video retrieval systems, as users shift from text based retrieval systems to content based retrieval systems. Selection of extracted features play an important ... More
Quantum dot with spin-orbit interaction in noncommutative phase space and analog Landau levelsJun 30 2009We have studied a quantum dot with Rashba spin orbit interaction on a plane where the position and momentum coordinates are considered to be noncommutative. The energy spectrum of the system is found to be equivalent to that of a quantum dot with Rashba ... More
Content based video retrievalNov 20 2012Content based video retrieval is an approach for facilitating the searching and browsing of large image collections over World Wide Web. In this approach, video analysis is conducted on low level visual properties extracted from video frame. We believed ... More
Probing space-time structure of new physics with polarized beams at the ILCJul 03 2006At the International Linear Collider large beam polarization of both the electron and positron beams will enhance the signature of physics due to interactions that are beyond the Standard Model. Here we review our recently obtained results on a general ... More
Operator Approach to Isospin Violation in Pion PhotoproductionFeb 02 2006Unambiguous isospin violation in the strong interaction sector is a key issue in low energy hadronic physics, both experimentally and theoretically. Bernstein has employed the Fermi-Watson theorem to demonstrate that pion photoproduction is a process ... More
Review of chiral perturbation theoryApr 07 2003A review of chiral perturbation theory and that of recent developments on the comparison of its predictions with experiment is presented. Some interesting topics with scope for further elaboration are touched upon.
Interaction of neutrons with alpha particles: A tribute to Heinz BarschallMar 16 2015As a tribute to our teacher and mentor on the occasion of his centennial celebration, we provide a brief historical overview and a summary of sustained interest in the topic of interaction of neutrons with alpha particles.
Spin glasses, the quantum annealing, colloidal glasses and crystals: exploring complex free-energy landscapesSep 09 2013Glassy behavior is one of the main open problems in condensed matter physics. In this thesis, we approach the problem by studying spin-glasses and colloids, using several complementary strategies. From the point of view of model building, we propose a ... More
Evolution equations for a cubic stochastic processMar 12 2010By analogue of [1,2] we define a cubic stochastic process and study evolution (dynamics) of a system $E$ which contains at least three elements.
In-Medium Properties of HadronsAug 24 2006A diverse experimental program for the study of the photoproduction of mesons off nuclei has been carried out - and is still running - at the Mainz MAMI and Bonn ELSA electron accelerators with the TAPS, Crystal Barrel, and Crystal Ball calorimeters. ... More
Meson photoproduction in the first and second resonance regionApr 02 2003The study of baryon resonances via meson photoproduction reactions on the free proton and on nucleons in the nuclear medium is discussed. Special emphasis is laid on the production of neutral mesons which due to the suppression of non-resonant backgrounds ... More
Dynamical peculiarities of the nonlinear quasiclassical systemsOct 28 1996The quantum-classical correspondence for dynamics of the nonlinear classically chaotic systems is analysed. The problem of quantum chaos consists of two parts: the quasiclassical quantisation of the chaotic systems and attempts to understand the classical ... More
ON THE QUANTUM EVOLUTION OF CHAOTIC SYSTEMS AFFECTED BY REPEATED FREQUENT MEASUREMENTMar 27 1995Apr 03 1995We investigate the effect of repeated measurement for quantum dynamics of the suppressed systems which classical counterparts exhibit chaos. The essential feature of such systems is the quantum localization phenomena strongly limiting motion in the energy ... More
Gamma-Ray Bursts and Particle AstrophysicsJul 24 2008Gamma-ray bursts are violent events occurring randomly in the sky. In this review, I will present the fireball model, proposed to explain the phenomenon of gamma-ray bursts. This model has important consequences for the production and observation at Earth ... More
Hopf Bifurcation in an Oscillatory-Excitatory Reaction-Diffusion Model with Spatial heterogeneityAug 13 2016We focus on the qualitative analysis of a reaction-diffusion with spatial heterogeneity near a bifurcation. The system is a generalization of the well known FitzHugh-Nagumo system in which the excitability parameter is space dependent. This heterogeneity ... More
Kinks Dynamics in One-Dimensional Coupled Map LatticesOct 20 1994We examine the problem of the dynamics of interfaces in a one-dimensional space-time discrete dynamical system. Two different regimes are studied : the non-propagating and the propagating one. In the first case, after proving the existence of such solutions, ... More
Nuclear Data Resources for Capture gamma-Ray Spectroscopy and Related TopicsAug 23 2011Nuclear reaction data play an important role in nuclear reactor, medical, and fundamental science and national security applications. The wealth of information is stored in internally adopted ENDF-6 and EXFOR formats. We present a complete calculation ... More
A Nuclear Data Approach for the Hubble Constant MeasurementsJun 09 2015Aug 22 2015An extraordinary number of Hubble constant measurements challenges physicists with selection of the best numerical value. The standard U.S. Nuclear Data Program (USNDP) codes and procedures have been applied to resolve this issue. The nuclear data approach ... More
Comment on "Precise half-life values for two-neutrino double beta decay"May 13 2010The results by A.S. Barabash [Phys. Rev. {\bf C 81}, 035501 (2010)] are shown to be incomplete. Tellurium data sets were reanalyzed using the best practices of ENSDF evaluations. Present analysis indicates much higher value for the 2$\nu$-mode half-life ... More
On Double-Beta Decay Half-Life Time SystematicsApr 19 2010Recommended 2 $\beta$ (2 $\nu$) half-life values and their systematics were analyzed in the frame- work of a simple empirical approach. T$^{2 \nu}$$_{1/2}$ ~ 1/E$^{8}$ trend has been observed for $^{128,130}$Te recommended values. This trend was used ... More
Super KEKB / Belle II ProjectJun 22 2010We present the status of the KEKB collider and the Belle detector upgrade, along with several examples of physics measurements to be performed with Belle II at Super KEKB.
D^0 MixingMay 07 2009An overview of selected experimental results in the field of $D^0$-$\bar{D}^0$ oscillations is presented. The average results for the mixing parameters, $x=(0.89\pm{0.26\atop 0.27})%$ and $y=(0.75\pm{0.17\atop 0.18})%$, exclude the no-mixing hypothesis ... More
Closed String Field Theory: An IntroductionMay 07 1993In these introductory notes I explain some basic ideas in string field theory. These include: the concept of a string field, the issue of background independence, the reason why minimal area metrics solve the problem of generating all Riemann surfaces ... More
A model for $q^2\bar{q}^2$ systems illustrated by an application to $K\bar{K}$ scatteringJan 26 1994In the paper is presented a four-body potential model for $q^2\bar{q}^2$ systems which includes both the spin and flavour degrees of freedom, extending the formalism presented already in the spin independent situation. This allows an application to a ... More
Perturbations of ionization fractions at the cosmological recombination epochMar 24 2006May 25 2006A development of perturbations of number densities of ions and electrons during recombination epoch is analysed. The equations for relative perturbations of ionization fractions were derived from the system of equations for accurate computation of the ... More
Best-fit parameters of MDM model from Abell-ACO power spectra and mass functionMar 23 1999The possibility of determining MDM model parameters on the basis of observable data on the Abell-ACO power spectrum and mass function is analysed. It is shown that spectrum area corresponding to these data is sensitive enough to such MDM model parameters ... More
Unified dispersive approach to $γ^*\toγππ$ and $γγ\toππ$Dec 02 2013A representation of the amplitude $\gamma^*(q^2)\to\gamma\pi\pi$ is proposed which combines large $N_c$ chiral resonance Lagrangian modelling with general unitarity and analyticity properties. The amplitude is constrained from $\gamma\gamma$ scattering ... More
Chiral perturbation theory: a basic introductionJul 21 2004Sep 01 2004Chiral perturbation theory is a very general expansion method which can be applied to any dynamical system which has continuous global symmetries and in which the ground state breaks some of these spontaneously. In these lectures we explain at a basic ... More
Measurement of Mass and Spin of Black Holes with QPOsOct 18 2007There are now four low mass X-ray binaries with black holes which show twin resonant-like HFQPOs. Similar QPOs might have been found in Sgr A*. I review the power spectral density distributions of the three X-ray flares and the six NIR flares published ... More
In-orbit performance of the XMM-Newton X-ray telescopes: images and spectraSep 21 2001The performance of the three X-ray telescopes on-board of XMM-Newton is evaluated addressing imaging characteristics and effective collecting area. The agreement with ground calibration data is excellent. The analysis of images and spectra of cosmic X-ray ... More
On some relations between generalized associatorsSep 15 2006Let Phi be the KZ associator and Psi_N be its analogue for N-th roots of 1. We prove a hexagon relation for Psi_4. Similarly to the Broadhurst (for Psi_2) and Okuda (for Psi_4) duality relations, it relies on the "supplementary" (i.e., non-dihedral) symmetries ... More
Nilpotent action on the KdV variables and 2-dimensional Drinfeld-Sokolov reductionNov 28 1993We note that a version ``with spectral parameter'' of the Drinfeld-Sokolov reduction gives a natural mapping from the KdV phase space to the group of loops with values in $\widehat N_{+}/A, \widehat N_{+}$~: affine nilpotent and $A$ principal commutative ... More
Flat connections on configuration spaces and formality of braid groups of surfacesDec 05 2011We construct an explicit bundle with flat connection on the configuration space of n points of a complex curve. This enables one to recover the `formality' isomorphism between the Lie algebra of the prounipotent completion of the pure braid group of n ... More
Large N expansion of the 2-matrix modelOct 04 2002We present a method, based on loop equations, to compute recursively all the terms in the large $N$ topological expansion of the free energy for the 2-hermitian matrix model. We illustrate the method by computing the first subleading term, i.e. the free ... More
Search for Low-Mass Dark Matter at BABARMay 15 2012Jun 01 2012This review briefly describes light dark matter searches performed by the BABAR experiment. Although dark matter candidates have traditionally been associated with heavy particles appearing in extensions of the Standard Model, a lighter component remains ... More
Phases and Structures of Interstellar GasJun 12 1999The thermal and chemical phases of the cool component of interstellar gas are discussed. Variations with galactocentric radius and from galaxy to galaxy are mostly the result of changes in the ambient interstellar pressure and radiation field. Interstellar ... More
Particle linear theory on a self-gravitating perturbed cubic Bravais latticeApr 16 2008Sep 17 2008Discreteness effects are a source of uncontrolled systematic errors of N-body simulations, which are used to compute the evolution of a self-gravitating fluid. We have already developed the so-called "Particle Linear Theory" (PLT), which describes the ... More
Topologically stable gapless phases of time-reversal invariant superconductorsSep 30 2009Apr 21 2010We show that time-reversal invariant superconductors in d=2 (d=3) dimensions can support topologically stable Fermi points (lines), characterized by an integer topological charge. Combining this with the momentum space symmetries present, we prove analogs ... More
Higgs Boson Resummation via Bottom-Quark FusionJul 21 2004The region of small transverse momentum in q-qbar- and gg-initiated processes must be studied in the framework of resummation to account for the large, logarithmically-enhanced contributions to physical observables. In this letter, we study resummed differential ... More
Next-to-leading Log Resummation of Scalar and Pseudoscalar Higgs Boson Differential Cross-Sections at the LHC and TevatronMay 22 2004Jun 22 2004The region of small transverse momentum in q qbar- and gg-initiated processes must be studied in the framework of resummation to account for the large, logarithmically-enhanced contributions to physical observables. In this paper, we will calculate the ... More
Dynamical free energy and the Loschmidt-echo for a class of quantum quenches in the Heisenberg spin chainAug 14 2013Oct 03 2013We consider a class of global quantum quenches in the Heisenberg XXZ spin chain, where the initial states are given by products of local two-site states. The two main examples are the N\'eel state and the dimer state. We derive an exact analytic result ... More
Mean values of local operators in highly excited Bethe statesSep 23 2010Dec 08 2010We consider expectation values of local operators in (continuum) integrable models in a situation when the mean value is calculated in a single Bethe state with a large number of particles. We develop a form factor expansion for the thermodynamic limit ... More
Approximate Controlability by Control Constraints for Infinite Dimensional SystemsApr 01 1996For linear infinite systems the approximate controllability problem by control constraints is considered. Controllability conditions represented via system parameters are obtained. Partial differential control systems and control systems with delays are ... More
Far-infrared Point SourcesMar 08 1999The analysis of the submm anisotropies that will be mapped by the forthcoming MAP and PLANCK satellites requires careful foreground subtraction before measuring CMB fluctuations. Among these, the foreground due to IR/submm thermal radiation from dusty ... More
Translation-covariant Markovian master equation for a test particle in a quantum fluidJul 02 2001A recently proposed master equation in the Lindblad form is studied with respect to covariance properties and existence of a stationary solution. The master equation describes the interaction of a test particle with a quantum fluid, the so-called Rayleigh ... More
Completely Positive Quantum DissipationFeb 29 2000A completely positive master equation describing quantum dissipation for a Brownian particle is derived starting from microphysical collisions, exploiting a recently introduced approach to subdynamics of a macrosystem. The obtained equation can be cast ... More
Penetration through a wall: Is it reality?Aug 25 2011A tennis ball is not expected to penetrate through a brick wall since a motion under a barrier is impossible in classical mechanics. With quantum effects a motion of a particle through a barrier is allowed due to quantum tunneling. According to usual ... More
Low-energy fusion caused by an interferenceJul 05 2012Nov 30 2012Fusion of two deuterons of room temperature energy is studied. The nuclei are in vacuum with no connection to any external source (electric or magnetic field, illumination, surrounding matter, traps, etc.) which may accelerate them. The energy of the ... More
Underbarrier interference and Euclidean resonanceJun 10 2008Quantum tunneling from a thin wire or a thin film through a static potential barrier in a zero magnetic field is studied. The wire or the film should satisfy a condition of transverse quantization of levels and be inhomogeneous. Depending on a form of ... More
Measurements of low energy e+e- hadronic cross sections and implications for the muon g-2Jul 17 2014Numerous channels of the cross section e+e- --> hadrons have been measured by the BABAR experiment using the ISR method. For the pi+pi-(gamma) and K+K-(gamma) channels, BABAR has pioneered the method based on the ratio between the hadronic mass spectra ... More
Exact Renormalization Group and Loop Variables: A Background Independent Approach to String TheoryAug 15 2015This paper is a self contained review of the Loop Variable approach to string theory. The Exact Renormalization Group is applied to a world sheet theory describing string propagation in a general background involving both massless and massive modes. This ... More
Gauge Invariant Action for the Open Bosonic String: Tachyon ActionFeb 06 2009A gauge invariant action for the open bosonic string has been proposed in an earlier paper. We work out the consequences of this proposal for the lowest mode, viz. the tachyon. The action can be calculated for generic momenta, perturbatively, order by ... More