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714
Evolutionary games on graphs
, 2007
"... Game theory is one of the key paradigms behind many scientific disciplines from biology to behavioral sciences to economics. In its evolutionary form and especially when the interacting agents are linked in a specific social network the underlying solution concepts and methods are very similar to ..."
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Cited by 143 (0 self)
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Game theory is one of the key paradigms behind many scientific disciplines from biology to behavioral sciences to economics. In its evolutionary form and especially when the interacting agents are linked in a specific social network the underlying solution concepts and methods are very similar to those applied in nonequilibrium statistical physics. This review gives a tutorialtype overview of the field for physicists. The first four sections introduce the necessary background in classical and evolutionary game theory from the basic definitions to the most important results. The fifth section surveys the topological complications implied by nonmeanfieldtype social network structures in general. The next three sections discuss in detail the dynamic behavior of three prominent classes of models: the Prisoner’s Dilemma, the Rock–Scissors–Paper game, and Competing Associations. The major theme of the review is in what sense and how the graph structure of interactions can modify and enrich the picture of long term behavioral patterns emerging in evolutionary games.
Solitons in the Higgs phase: The moduli matrix approach
 J. Phys. A
, 2006
"... Abstract. We review our recent work on solitons in the Higgs phase. We use U(NC) gauge theory with NF Higgs scalar fields in the fundamental representation, which can be extended to possess eight supercharges. We propose the moduli matrix as a fundamental tool to exhaust all BPS solutions, and to ch ..."
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Cited by 49 (16 self)
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Abstract. We review our recent work on solitons in the Higgs phase. We use U(NC) gauge theory with NF Higgs scalar fields in the fundamental representation, which can be extended to possess eight supercharges. We propose the moduli matrix as a fundamental tool to exhaust all BPS solutions, and to characterize all possible moduli parameters. Moduli spaces of domain walls (kinks) and vortices, which are the only elementary solitons in the Higgs phase, are found in terms of the moduli matrix. Stable monopoles and instantons can exist in the Higgs phase if they are attached by vortices to form composite solitons. The moduli spaces of these composite solitons are also worked out in terms of the moduli matrix. Webs of walls can also be formed with characteristic difference between Abelian and nonAbelian gauge theories. Instantonvortex systems, monopolevortexwall systems, and webs of walls in Abelian gauge theories are found to admit negative energy objects with the instanton charge (called intersectons), the monopole charge (called boojums) and the Hitchin charge, respectively. We characterize the total moduli space of these elementary as well as composite solitons. In particular the total moduli space of
Origin and Propagation of Extremely High Energy Cosmic Rays
 Phys. Rept
, 2000
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Inflationary cosmology: progress and problems
 Proceedings International School on Cosmology, Kish Island, Iran (Kluwer, Dordrecht) 2000) ePrint Archive: hepph/9910410
"... Abstract. These lecture notes 1 intend to form a short pedagogical introduction to inflationary cosmology, highlighting selected areas of recent progress such as reheating and the theory of cosmological perturbations. Problems of principle for inflationary cosmology are pointed out, and some new att ..."
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Cited by 40 (10 self)
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Abstract. These lecture notes 1 intend to form a short pedagogical introduction to inflationary cosmology, highlighting selected areas of recent progress such as reheating and the theory of cosmological perturbations. Problems of principle for inflationary cosmology are pointed out, and some new attempts at solving them are indicated, including a nonsingular Universe construction by means of higher derivative terms in the gravitational action, and the study of backreaction of cosmological perturbations. 1.
Gravitational Wave Experiments and Early Universe Cosmology
"... Gravitationalwave experiments with interferometers and with resonant masses can search for stochastic backgrounds of gravitational waves of cosmological origin. We review both experimental and theoretical aspects of the search for these backgrounds. We give a pedagogical derivation of the various r ..."
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Cited by 36 (0 self)
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Gravitationalwave experiments with interferometers and with resonant masses can search for stochastic backgrounds of gravitational waves of cosmological origin. We review both experimental and theoretical aspects of the search for these backgrounds. We give a pedagogical derivation of the various relations that characterize the response of a detector to a stochastic background. We discuss the sensitivities of the large interferometers under constructions (LIGO, VIRGO, GEO600, TAMA300, AIGO) or planned (Avdanced LIGO, LISA) and of the presently operating resonant bars, and we give the sensitivities for various twodetectors correlations. We examine the existing limits on the energy density in gravitational waves from nucleosynthesis, COBE and pulsars, and their effects on theoretical predictions. We discuss general theoretical principles for orderofmagnitude estimates of cosmological production mechanisms, and then we turn to specific theoretical predictions from inflation, string cosmology, phase transitions, cosmic strings and other mechanisms. We finally compare with the stochastic backgrounds of astrophysical origin.
Formation and evolution of cosmic Dstrings
 Cosmic F and Dstrings,” JHEP 0406
, 2004
"... We study the formation of D and Fcosmic strings in Dbrane annihilation after brane inflation. We show that Dstring formation by quantum de Sitter fluctuations is severely suppressed, due to suppression of RR field fluctuations in compact dimensions. We discuss the resonant mechanism of production ..."
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Cited by 27 (5 self)
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We study the formation of D and Fcosmic strings in Dbrane annihilation after brane inflation. We show that Dstring formation by quantum de Sitter fluctuations is severely suppressed, due to suppression of RR field fluctuations in compact dimensions. We discuss the resonant mechanism of production of D and Fstrings, which are formed as magnetic and electric flux tubes of the two orthogonal gauge fields living on the worldvolume of the unstable brane. We outline the subsequent cosmological evolution of the D−F string network. We also compare the nature of these strings with the ordinary cosmic strings and point out some differences and similarities. I.
Sums over topological sectors and quantization of FayetIliopoulos parameters,” arXiv:1012.5999 [hepth
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Fundamental cosmic strings
, 2005
"... Cosmic strings are linear concentrations of energy that may be formed at phase transitions in the very early universe. At one time they were thought to provide a possible origin for the density inhomogeneities from which galaxies eventually develop, though this idea has been ruled out, primarily by ..."
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Cited by 24 (1 self)
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Cosmic strings are linear concentrations of energy that may be formed at phase transitions in the very early universe. At one time they were thought to provide a possible origin for the density inhomogeneities from which galaxies eventually develop, though this idea has been ruled out, primarily by observations of the cosmic microwave background (CMB). Fundamental strings are the supposed building blocks of all matter in superstring theory or its modern version, Mtheory. These two concepts were originally very far apart, but recent developments have brought them closer. The ‘braneworld ’ scenario in particular suggests the existence of macroscopic fundamental strings that could well play a role very similar to that of cosmic strings. In this paper, we outline these new developments, and also analyze recent observational evidence, and prospects for the future. 1 Spontaneous symmetry breaking This is a feature of many physical systems, often accompanying a phase transition. For example, there are no preferred directions in a liquid such as water — it has