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Nanoscale domains in ionic liquids: A statistical mechanics definition for molecular dynamics studiesMar 14 2019One of the many open questions concerning Ionic Liquids (ILs) is the existence of nanoscale supramolecular domains which characterize the bulk. The hypothesis of their existence does not meet a general consensus since their definition seems to be based ... More

The Rise and Fall of Anomalies in Tetrahedral LiquidsJul 28 2011The thermodynamic liquid-state anomalies and associated structural changes of the Stillinger-Weber family of liquids are mapped out as a function of the degree of tetrahedrality of the interaction potential, focusing in particular on tetrahedrality values ... More

Obstacle evasion using fuzzy logic in a sliding blades problem environmentMay 03 2016This paper discusses obstacle avoidance using fuzzy logic and shortest path algorithm. This paper also introduces the sliding blades problem and illustrates how a drone can navigate itself through the swinging blade obstacles while tracing a semi-optimal ... 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

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

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

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

Gauge Invariant Action for the Open Bosonic StringDec 11 2007The issue of space time gauge invariance for the bosonic string has been earlier addressed using the loop variable formalism. In this paper the question of obtaining a gauge invariant action for the open bosonic string is discussed. The derivative w.r.t ... More

Loop Variables and Gauge Invariance in Closed Bosonic String TheoryMay 13 2004We extend an earlier proposal for a gauge invariant description of off-shell open strings (at tree level), using loop variables, to off-shell closed strings (at tree level). The basic idea is to describe the closed string amplitudes as a product of two ... More

On Factorizing Correlation Functions in String Theory Using Loop VariablesJul 28 1995Factorization of string amplitudes is one way of constructing string interaction vertices. We show that correlation functions in string theory can be conveniently factorized using loop variables representing delta functionals. We illustrate this construction ... More

A Comparison of the Proper Time Equation and the Renormalization Group $β$-Function in String TheoryMay 22 1995Jun 12 1995It is known that there is a proportionality factor relating the $\beta$-function and the equations of motion viz. the Zamolodchikov metric. Usually this factor has to be obtained by other methods. The proper time equation, on the other hand, is the full ... More

The Hagedorn Transition and the Matrix Model for StringsMay 20 1998Jul 23 1998We use the Matrix formalism to investigate what happens to strings above the Hagedorn temperaure. We show that it is not a limiting temperature but a temperature at which the continuum string picture breaks down. We study a collection of $N$ D-0-branes ... More

Quark Diffusion Along the Critical LineJun 18 2008Jun 19 2008The quark diffusion coefficient in the critical window near $T_c$ and at moderate values of the chemical potential is evaluated.

THE INTERPLAY OF THE K+K- ATOM AND THE f_0(975) RESONANCEMar 20 1995We predict that production of the K+K- atom in pd-3^HeX and similar reactions exhibits a drastic missing mass spectrum due to the interplay with f_0(975) resonance. We point out that high precision studies of the K+K- atom may shed a new light on the ... More

Quark matter conductivity in strong magnetic backgroundFeb 07 2011Applying the ideas and methods of condensed matter physics we calculate the quantum conductivity of quark matter in magnetic field. In strong field quantum conductivity is proportional to the square root of the field.

T-duality as coordinates permutation in double spaceJan 05 2015Mar 17 2015We introduce the $2D$ dimensional double space with the coordinates $Z^M= (x^\mu, y_\mu)$ which components are the coordinates of initial space $x^\mu$ and its T-dual $y_\mu$. We shall show that in this extended space the T-duality transformations can ... More

The normal bundle of a rational curve on a generic quintic threefoldAug 30 2015This is another proof of the same result in [9]. Let $X_0$ be a generic quintic hypersurface in $\mathbf P^4$ over $\mathbb C$ and $c_0$ a regular map $\mathbf P^1\to X_0$ that is generically one-to-one to its image. In this paper, we show (1) $c_0$ must ... More

Photostrictive materialsMar 05 2015Light-matter interactions that lead to nonthermal changes in size of the sample constitute a photostrictive effect in many compounds. The photostriction phenomenon was observed in four main groups of materials, ferroelectrics, polar, and non-polar semiconductors, ... More

Inference of Coefficients for Use in Phase Correction IMar 06 2009Mar 19 2009We present a Bayesian approach to calculating the coefficients that convert the outputs of ALMA 183 GHz water-vapour radiometers into estimates of path fluctuations which can then be used to correct the observed interferometric visibilities. The key features ... More

Localization and Nonperturbative Local Quantum PhysicsMay 15 1998The main content of this treatise is a new concept in nonperturbative non-Lagrangian QFT which explains and extends the ad hoc constructions in low-dimensional models and incorporates them together with the higher dimensional theories into a new construction ... More

The Molecular Aharonov-Bohm effect ReduxMay 18 2016A solvable molecular collision model that predicts Aharonov-Bohm (AB) like scattering in the adiabatic approximation is introduced. For it, we propagate coupled channel wave packets without resorting to a Born-Oppenheimer (BO) approximation. In those, ... More

Geometric Phase OpticsMay 08 2012May 09 2012We introduce, and propagate wave-packet solutions of, a single qubit system in which geometric gauge forces and phases emerge. We investigate under what conditions non-trivial gauge phenomena arise, and demonstrate how symmetry breaking is an essential ... More

Comment on "Nuclear Emissions During Self-Nucleated Acoustic Cavitation"Mar 08 2006Sep 12 2006In a recent Letter to PRL, Taleyarkhan and coauthors claim to observe DD fusion produced by acoustic cavitation. Among other evidence, they provide a proton recoil spectrum that they interpret as arising from 2.45 MeV DD fusion neutrons. My analysis concludes ... More

The eta' and the topological charge densityFeb 15 2000We compare two different frameworks which have been proposed to include the eta' in chiral perturbation theory. The equivalence of these two approaches is shown both for the purely mesonic case and in the presence of the ground state baryon octet. The ... More

Rings of definition of smooth and proper dg-algebrasNov 17 2006Jun 01 2010This is a companion paper to math.AT/0609762. For a filtered colimit of commutative rings k=colim k_i, we prove that the homotopy theory of smooth and proper dg-algebras over k is the colimit of the homotopy theories of smooth and proper dg-algebras over ... More

Higher and derived stacks: a global overviewApr 24 2006May 13 2006These are expended notes of my talk at the summer institute in algebraic geometry (Seattle, July-August 2005), whose main purpose is to present a global overview on the theory of higher and derived stacks. This text is far from being exhaustive but is ... More

Derived Hall AlgebrasJan 21 2005Apr 25 2006The purpose of this work is to define a derived Hall algebra $\mathcal{DH}(T)$, associated to any dg-category $T$ (under some finiteness conditions). Our main theorem states that $\mathcal{DH}(T)$ is associative and unital. It is shown that $\mathcal{DH}(T)$ ... More

The homotopy theory of dg-categories and derived Morita theoryAug 24 2004Oct 19 2006The main purpose of this work is the study of the homotopy theory of dg-categories up to quasi-equivalences. Our main result provides a natural description of the mapping spaces between two dg-categories $C$ and $D$ in terms of the nerve of a certain ... More

Affine stacks (Champs affines)Dec 21 2000Apr 25 2006This is an expended and revised version of the preprint "Schematization of homotopy types". The purpose of this work is to introduce a notion of \emph{affine stacks}, which is a homotopy version of the notion of affine schemes, and to give several applications ... More

On motives for Deligne-Mumford stacksJun 21 2000We define and compare two different definitions of Chow motives for Deligne-Mumford stacks, associated with two definitions of Chow rings. The main result we prove is that both categories of motives are equivalent to the usual category of motives of algebraic ... More

Toward a Galoisian interpretation of homotopy theoryJul 26 2000Apr 21 2002Given any pointed CW complex (X,x), it is well known that the fondamental group of X pointed at x is naturally isomorphic to the automorphism group of the functor which associates to a locally constant sheaf on X its fibre at x. The purpose of this work ... More

Theory of the rotation of Janus and EpimetheusDec 24 2009The Saturnian coorbital satellites Janus and Epimetheus present a unique dynamical configuration in the Solar System, because of high-amplitude horseshoe orbits, due to a mass ratio of order unity. As a consequence, they swap their orbits every 4 years, ... More

Theoretical Resolution of Magnetic Reconnection in High Energy PlasmasJun 14 2007The formation of macroscopic reconnected magnetic structures (islands) have been observed in advanced experiments on weakly collisional, well confined plasmas while established theories of the drift-tearing modes, which depend strongly on the electron ... More

Interaction with a pre and post selected environment and recoherenceJan 31 1995The interaction of an open system $\s$ with a pre- and post-selected environment is studied. In general, under such circumstances $\s$ can not be described in terms of a density matrix, {\it even when $\s$ in not post-selected}. However, a simple description ... More

Microscopic Deterministic Dynamics and Persistence ExponentSep 22 1999Numerically we solve the microscopic deterministic equations of motion with random initial states for the two-dimensional $\phi^4$ theory. Scaling behavior of the persistence probability at criticality is systematically investigated and the persistence ... More

Counting Gribov copiesJan 05 2009We show that an explicit counting of Gribov copies can shed light on the infrared behavior of non-abelian gauge theories. A power-law growth of the number of copies suppresses gluon propagation while the distribution of copies along a gauge orbit implies ... More