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1,855
Phase Transitions in Driven Diffusive Systems With Random Rates
, 1996
"... We study a onedimensional driven lattice gas model in which quenched random jump rates are associated with the particles. Under suitable conditions on the distribution of jump rates the model displays a phase transition from a high density `laminar' phase with product measure to a low density ..."
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Cited by 82 (5 self)
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We study a onedimensional driven lattice gas model in which quenched random jump rates are associated with the particles. Under suitable conditions on the distribution of jump rates the model displays a phase transition from a high density `laminar' phase with product measure to a low density `jammed' phase in which the interparticle spacings have no stationary distribution. Using a waiting time representation the phase transition is shown to be equivalent to a pinning transition of directed polymers with columnar defects. The phenomenon is argued to have a natural realization in traffic flow.
Experimental Issues in Coherent QuantumState Manipulation of Trapped Atomic Ions
, 1998
"... this paper, we investigate a subset of these topics which involve the coherent manipulation of quantum states of trapped atomic ions. The focus will be on a proposal to implement quantum logic and quantum computation using trapped ions [1]. However, we will also consider related work on the generati ..."
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Cited by 78 (11 self)
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this paper, we investigate a subset of these topics which involve the coherent manipulation of quantum states of trapped atomic ions. The focus will be on a proposal to implement quantum logic and quantum computation using trapped ions [1]. However, we will also consider related work on the generation of nonclassical states of motion and entangled states of trapped ions [239]. Many of these ideas have been summarized in a recent review [40].
Modelindependent analysis of soft terms in effective supergravity and in string theory
 PHYS. LETT. B306
, 1993
"... We discuss supersymmetry breakdown in effective supergravities such as emerge in the lowenergy limit of superstring theory. Without specifying the precise trigger of the breakdown, we analyse the soft parameters in the Lagrangian of the supersymmetrized Standard Model. ..."
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Cited by 76 (1 self)
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We discuss supersymmetry breakdown in effective supergravities such as emerge in the lowenergy limit of superstring theory. Without specifying the precise trigger of the breakdown, we analyse the soft parameters in the Lagrangian of the supersymmetrized Standard Model.
Field Dependent Gauge Couplings in Locally Supersymmetric Effective Quantum Field Theories,” Nucl. Phys. B422
, 1994
"... We investigate the field dependence of the gauge couplings of locally supersymmetric effective quantum field theories. We find that the Weyl rescaling of supergravity gives rise to WessZumino terms that affect the gauge couplings at the oneloop level. These WessZumino terms are crucial in assurin ..."
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Cited by 53 (0 self)
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We investigate the field dependence of the gauge couplings of locally supersymmetric effective quantum field theories. We find that the Weyl rescaling of supergravity gives rise to WessZumino terms that affect the gauge couplings at the oneloop level. These WessZumino terms are crucial in assuring supersymmetric consistency of both perturbative and nonperturbative gauge interactions. At the perturbative level, we distinguish between the holomorphic Wilsonian gauge couplings and the physicallymeasurable momentumdependent effective gauge couplings; the latter are affected by the Konishi and the superWeyl anomalies and their fielddependence is nonholomorphic. At the nonperturbative level, we show how consistency of the scalar potential generated by infraredstrong gauge interactions with the local supersymmetry requires a very specific form of the effective superpotential. We use this superpotential to determine the dependence of the supersymmetric condensates of a strongly interacting gauge theory on its (fielddependent) Wilsonian gauge coupling and the Yukawa couplings of the matter fields. The article concludes with the discussion of the fielddependent nonperturbative phenomena in the context of string unification. 2
Lattice Boltzmann simulations of nonideal fluids
, 1995
"... A lattice Boltzmann scheme able to model the hydrodynamics of phase separation and twophase flow is described. Thermodynamic consistency is ensured by introducing a nonideal pressure tensor directly into the collision operator. We also show how an external chemical potential can be used to supplem ..."
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Cited by 52 (1 self)
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A lattice Boltzmann scheme able to model the hydrodynamics of phase separation and twophase flow is described. Thermodynamic consistency is ensured by introducing a nonideal pressure tensor directly into the collision operator. We also show how an external chemical potential can be used to supplement standard boundary conditions in order to investigate the effect of wetting on phase separation and fluid flow in confined geometries. The approach has the additional advantage of reducing many of the unphysical discretisation problems common to previous lattice Boltzmann methods. PACS numbers: 02.70Ns, 05.70Fh, 47.11+j 1 The hydrodynamics and kinetics of twocomponent fluids present a wealth of physical problems of both fundamental and technological importance [1]. There is much current interest in the relevance of hydrodynamics to spinodal decomposition [2] and the effects of substrates with different wetting properties on phase separation and domain growth [3]. In addition, the flow properties of multicomponent systems, particularly in porous media, have
Anomalous diffusion in the presence of external forces: Exact timedependent solutions and their thermostatistical basis, Phys
 Rev. E
, 1996
"... The optimization of the usual entropy S1[p] = − ∫ du p(u) ln p(u) under appropriate constraints is closely related to the Gaussian form of the exact timedependent solution of the FokkerPlanck equation describing an important class of normal diffusions. We show here that the optimization of the ..."
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Cited by 41 (13 self)
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The optimization of the usual entropy S1[p] = − ∫ du p(u) ln p(u) under appropriate constraints is closely related to the Gaussian form of the exact timedependent solution of the FokkerPlanck equation describing an important class of normal diffusions. We show here that the optimization of the generalized entropic form Sq[p] = {1 − ∫ du [p(u)] q}/(q − 1) (with q = 1 + µ − ν ∈ R) is closely related to the calculation of the exact timedependent solutions of a generalized, nonlinear, Fokker Planck equation, namely ∂ ∂t pµ = − ∂ ∂x [F(x)pµ] + D ∂2 ∂x 2p ν, associated with anomalous diffusion in the presence of the external force F(x) = k1 −k2x. Consequently, paradigmatic types of normal (q = 1) and anomalous (q ̸ = 1) diffusions occurring in
Generation of NonClassical Motional States of a Trapped Atom
, 1996
"... We report the creation of thermal, Fock, coherent, and squeezed states of motion of a harmonically bound 9 Be + ion. The last three states are coherently prepared from an ion which has been initially lasercooled to the zeropoint of motion. The ion is trapped in the regime where the coupling be ..."
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Cited by 40 (5 self)
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We report the creation of thermal, Fock, coherent, and squeezed states of motion of a harmonically bound 9 Be + ion. The last three states are coherently prepared from an ion which has been initially lasercooled to the zeropoint of motion. The ion is trapped in the regime where the coupling between its motional and internal states, due to applied (classical) radiation, can be described by a JaynesCummingstype interaction. With this coupling, the evolution of the internal atomic state provides a signature of the number state distribution of the motion. PACS numbers:42.50.Vk, 32.80.Pj, 32.80.Qk Typeset using REVT E X Nonclassical states of the harmonic oscillator associated with a single mode of the radiation field (for example, squeezed states) have been a subject of considerable interest. One method for analyzing these states has been through the dynamics of a single, twolevel atom which radiatively couples to the single mode radiation field. This system, described by the Ja...
BoseEinstein Condensation of Atomic Hydrogen,” Phys
 Rev. Lett
, 1998
"... We report observation of BoseEinstein condensation of a trapped, dilute gas of atomic hydrogen. The condensate and normal gas are studied by twophoton spectroscopy of the 1S2S transition. Interactions among the atoms produce a shift of the resonance frequency proportional to density. The condensa ..."
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Cited by 35 (1 self)
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We report observation of BoseEinstein condensation of a trapped, dilute gas of atomic hydrogen. The condensate and normal gas are studied by twophoton spectroscopy of the 1S2S transition. Interactions among the atoms produce a shift of the resonance frequency proportional to density. The condensate is clearly distinguished by its large frequency shift. The peak condensate density is 4.8 ± 1.1 × 10 15 cm −3, corresponding to a condensate population of 10 9 atoms. The BEC transition occurs at about T = 50 µK and n = 1.8 × 10 14 cm −3. Typeset using REVTEX 1 The search for BoseEinstein condensation in dilute atomic gases began in 1978 [1], precipitated by the suggestion of Stwalley and Nasanow [2] that spinpolarized atomic hydrogen should be an ideal candidate for the study of such extreme quantum behavior. Dilute gases of H were first stabilized by Silvera and Walraven [3]. Subsequent attempts to achieve BEC were thwarted by recombination on the walls of the confinement cell [4]. In order to create
Nonperturbative dynamics in supersymmetric gauge theories
, 1997
"... I give an introductory review of recent, fascinating developments in supersymmetric gauge theories. I explain pedagogically the miraculous properties of supersymmetric gauge dynamics allowing one to obtain exact solutions in many instances. Various dynamical regimes emerging in supersymmetric Quantu ..."
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Cited by 33 (3 self)
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I give an introductory review of recent, fascinating developments in supersymmetric gauge theories. I explain pedagogically the miraculous properties of supersymmetric gauge dynamics allowing one to obtain exact solutions in many instances. Various dynamical regimes emerging in supersymmetric Quantum Chromodynamics and its generalizations are discussed. I emphasize those features that have a chance of survival in QCD and those which are drastically different in supersymmetric and nonsupersymmetric gauge theories. Unlike most of the recent reviews focusing almost entirely on the progress in extended supersymmetries (the SeibergWitten solution of N = 2 models), these lectures are mainly devoted to N = 1 theories. The primary task is
Black hole radiation in the presence of a short distance cutoff Phys
 Rev. D 48 728 (Jacobson T 1993 Preprint hepth/9303103
, 1993
"... A derivation of the Hawking effect is given which avoids reference to field modes above some cutoff frequency ωc ≫ M −1 in the freefall frame of the black hole. To avoid reference to arbitrarily high frequencies, it is necessary to impose a boundary condition on the quantum field in a timelike regio ..."
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Cited by 28 (4 self)
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A derivation of the Hawking effect is given which avoids reference to field modes above some cutoff frequency ωc ≫ M −1 in the freefall frame of the black hole. To avoid reference to arbitrarily high frequencies, it is necessary to impose a boundary condition on the quantum field in a timelike region near the horizon, rather than on a (spacelike) Cauchy surface either outside the horizon or at early times before the horizon forms. Due to the nature of the horizon as an infinite redshift surface, the correct boundary condition at late times outside the horizon cannot be deduced, within the confines of a theory that applies only below the cutoff, from initial conditions prior to the formation of the hole. A boundary condition is formulated which leads to the Hawking effect in a cutoff theory. It is argued that it is possible the boundary condition is not satisfied, so that the spectrum of black hole radiation may be significantly different from that predicted by Hawking, even without the backreaction near the horizon becoming of order unity relative to the curvature.