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2002b Parrondo games as a lattice gas automata
 J. Stat. Phys
"... Parrondo games are coin flipping games with the surprising property that alternating plays of two losing games can produce a winning game. We show that this phenomenon can be modelled by probabilistic lattice gas automata. Furthermore, motivated by the recent introduction of quantum coin flipping ga ..."
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Cited by 14 (1 self)
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Parrondo games are coin flipping games with the surprising property that alternating plays of two losing games can produce a winning game. We show that this phenomenon can be modelled by probabilistic lattice gas automata. Furthermore, motivated by the recent introduction of quantum coin flipping games, we show that quantum lattice gas automata provide an interesting definition for quantum Parrondo games.
Dürr D.: Adiabatic Pair Creation
 in Heavy Ion and Laser Fields, arXiv:hepth/0609200v2
"... We give here the proof that pair creation in a time dependent potentials is possible. It happens with probability one if the potential changes adiabatically in time and becomes overcritical, that is when an eigenvalue enters the upper spectral continuum. The potential may be assumed to be zero at la ..."
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Cited by 3 (2 self)
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We give here the proof that pair creation in a time dependent potentials is possible. It happens with probability one if the potential changes adiabatically in time and becomes overcritical, that is when an eigenvalue enters the upper spectral continuum. The potential may be assumed to be zero at large negative and positive times. The rigorous treatment of
The Clifford Algebra Approach to Quantum Mechanics A: The Schrödinger and Pauli Particles
"... PACS numbers: Using a method based on Clifford algebras taken over the reals, we present here a fully relativistic version of the Bohm model for the Dirac particle. This model is different from the one originally proposed by Bohm and Hiley and by Doran and Lasenby. We obtain exact expressions for th ..."
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Cited by 3 (3 self)
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PACS numbers: Using a method based on Clifford algebras taken over the reals, we present here a fully relativistic version of the Bohm model for the Dirac particle. This model is different from the one originally proposed by Bohm and Hiley and by Doran and Lasenby. We obtain exact expressions for the Bohm energymomentum density, a relativistic quantum HamiltonJacobi for the conservation of energy which includes an expression for the quantum potential and a relativistic time development equation for the spin vectors of the particle. We then show that these reduce to the corresponding nonrelativistic expressions for the Pauli particle which have already been derived by Bohm, Schiller and Tiomno and in more general form by Hiley and Callaghan. In contrast to the original presentations, there is no need to appeal to classical mechanics at any stage of the development of the formalism. All the results for the Dirac, Pauli and Schrödinger cases are shown to emerge respectively from the hierarchy of Clifford algebras C13, C30, C01 taken over the reals as Hestenes has already argued. Thus quantum mechanics is emerging from one mathematical structure with no need to appeal to an external Hilbert space with wave functions.
Limits on the Applicability of Classical Electromagnetic Fields as Inferred from the Radiation Reaction
"... Can the wavelength of a classical electromagnetic field be arbitrarily small, or its electric field strength be arbitrarily large? If we require that the radiationreaction force on a charged particle in response to an applied field be smaller than the Lorentz force we find limits on the classical el ..."
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Cited by 2 (0 self)
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Can the wavelength of a classical electromagnetic field be arbitrarily small, or its electric field strength be arbitrarily large? If we require that the radiationreaction force on a charged particle in response to an applied field be smaller than the Lorentz force we find limits on the classical electromagnetic field that herald the need for a better theory, i.e., one in better accord with experiment. The classical limitations find ready interpretation in quantum electrodynamics. The examples of Compton scattering and the QED critical field strength are discussed. It is still open to conjecture whether the present theory of QED is valid at field strengths beyond the critical field revealed by a semiclassical argument. 1
XVIII Physics in Collision
"... After a brief review of higherorder QED effects, a survey is made of novel aspects of QED with emphasis on recent experimental results in strongfield QED: nonlinear Compton scattering and multiphoton pair creation by light. 1 HigherOrder QED Effects Quantum Electrodynamics (QED) describes the in ..."
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After a brief review of higherorder QED effects, a survey is made of novel aspects of QED with emphasis on recent experimental results in strongfield QED: nonlinear Compton scattering and multiphoton pair creation by light. 1 HigherOrder QED Effects Quantum Electrodynamics (QED) describes the interactions between charged particles that are mediated by quanta (photons) of the electromagnetic field. The simplest QED processes involve only a single photon, as represented by exchange and annihilation diagrams (Fig. 1). These processes involve two vertices of the form flee (where e represents an electric charge, not necessarily an electron). The process that consists only of emission of a real photon by a charged particle is forbidden by energymomentum conservation. We may then say that higherorder QED is any process that involves more than two flee vertices. Higherorder QED processes are often divided into two groups: tree and loop. Loop processes involve one or more virtual pairs ...
Executive Summary
"... nalog of beamstrahlung to be studied. Measurement of the invariantmass spectrum of electronpositron pairs could clarify whether the positron peaks seen at Darmstadt in heavyion collisions are a strongfield QED effect. Electronlaser collisions at critical field strength may prove to be a highbr ..."
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nalog of beamstrahlung to be studied. Measurement of the invariantmass spectrum of electronpositron pairs could clarify whether the positron peaks seen at Darmstadt in heavyion collisions are a strongfield QED effect. Electronlaser collisions at critical field strength may prove to be a highbrightness source of positrons for future colliders. i Contents 1 Introduction 1 2 Experimental Setup 3 2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Beam Parameters and Event Rates . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 The Laser Interaction Points . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.4 The Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.5 Backgrounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3 Nonlinear Compton Scattering 14 4 Beamstrahlung 17 5 The Multiphoton BreitWheeler Process 18 6 The e<F19
unknown title
"... Abstract. We review the effects of strong background fields in noncommutative QED. Beginning with the noncommutative Maxwell and Dirac equations, we describe how combined noncommutative and strong field effects modify the propagation of fermions and photons. We extend these studies beyond the case o ..."
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Abstract. We review the effects of strong background fields in noncommutative QED. Beginning with the noncommutative Maxwell and Dirac equations, we describe how combined noncommutative and strong field effects modify the propagation of fermions and photons. We extend these studies beyond the case of constant backgrounds by giving a new and revealing interpretation of the photon dispersion relation. Considering scattering in background fields, we then show that the noncommutative photon is primarily responsible for generating deviations from strong field QED results. Finally, we propose a new method for constructing gauge invariant variables in noncommutative QED, and use it to analyse the physics of our null background fields. Key words: noncommutative QED; background fields
CONTENTS
, 2005
"... Crystals present a uniquely simple environment for the investigation of strong electromagnetic fields. When energetic charged particles are incident on crystals close to major crystallographic directions, their electromagnetic interactions depend crucially on the kinematic conditions. The coherence ..."
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Crystals present a uniquely simple environment for the investigation of strong electromagnetic fields. When energetic charged particles are incident on crystals close to major crystallographic directions, their electromagnetic interactions depend crucially on the kinematic conditions. The coherence of the crystalline field can produce very strong electric fields in the rest frame of the particle, exceeding the socalled Schwinger field or quantum critical field. In that domain, the radiation emission takes a substantial part of the electron energy and the “formation zone ” changes character. In this review the theory appropriate to the different kinematics domains is described, concentrating on the effects occurring at extreme fields. Properties discussed include strong field synchrotron radiation, channeling radiation, bremsstrahlung, and photon interactions. Applications are given to radiation sources,
Large orders in strongfield QED
, 2006
"... Abstract. We address the issue of largeorder expansions in strongfield QED. Our approach is based on the oneloop effective action encoded in the associated photon polarisation tensor. We concentrate on the simple case of crossed fields aiming at possible applications of highpower lasers to measu ..."
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Abstract. We address the issue of largeorder expansions in strongfield QED. Our approach is based on the oneloop effective action encoded in the associated photon polarisation tensor. We concentrate on the simple case of crossed fields aiming at possible applications of highpower lasers to measure vacuum birefringence. A simple nexttoleading order derivative expansion reveals that the indices of refraction increase with frequency. This signals normal dispersion in the smallfrequency regime where the derivative expansion makes sense. To gain information beyond that regime we determine the factorial growth of the derivative expansion coefficients evaluating the first 80 orders by means of computer algebra. From this we can infer a nonperturbative imaginary part for the indices of refraction indicating absorption (pair production) as soon as energy and intensity become (super)critical. These results compare favourably with an analytic evaluation of the polarisation tensor asymptotics. KramersKronig relations finally allow for a nonperturbative definition of the real parts as well and show that absorption goes hand in hand with anomalous dispersion for sufficiently large frequencies and fields. PACS numbers: 12.20.m, 42.50.Xa, 42.60.vLarge orders in strongfield QED 2 1.
Proposal for a STUDY OF QED AT CRITICAL FIELD STRENGTH IN INTENSE LASER–HIGH ENERGY ELECTRON COLLISIONS AT THE STANFORD LINEAR ACCELERATOR
, 1991
"... We propose a program of study of the interaction of electrons and photons in fields approaching the critical QED field strength of an electron rest energy per Compton wavelength. This can be achieved in collisions between the picosecond pulses of a teraWatt laser and a 50GeV electron beam. The phen ..."
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We propose a program of study of the interaction of electrons and photons in fields approaching the critical QED field strength of an electron rest energy per Compton wavelength. This can be achieved in collisions between the picosecond pulses of a teraWatt laser and a 50GeV electron beam. The phenomena accessible to study include nonlinear Compton scattering, trident production, and BreitWheeler pair production. The electric field at the laser focus is of similar strength to that of an electron bunch in future linear colliders, permitting a close analog of beamstrahlung to be studied. Measurement of the invariantmass spectrum of electronpositron pairs could clarify whether the positron peaks seen at Darmstadt in heavyion collisions are a strongfield QED effect. Electronlaser collisions at critical field strength may prove to be a highbrightness source of positrons for future colliders.