Nonlinear evolution of density and flow perturbations on a Bjorken background

• Verfasst von: Brouzakis, Nikos [VerfasserIn]
• Verfasst von: Flörchinger, Stefan [VerfasserIn]
• Titel: Nonlinear evolution of density and flow perturbations on a Bjorken background
• Verf.angabe: Nikolaos Brouzakis, Stefan Floerchinger, Nikolaos Tetradis, and Urs Achim Wiedemann
• Fussnoten: Gesehen am 24.11.2017
• Titel Quelle: Enthalten in: Physical review / D
• Jahr Quelle: 2015
• Band/Heft Quelle: 91(2015,6) Artikel-Nummer 065007, 20 Seiten
• ISSN Quelle: 1550-2368
• ISSN Quelle: 1089-4918
• DOI: doi:10.1103/PhysRevD.91.065007
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1565714261

Abstract

Density perturbations and their dynamic evolution from early to late times can be used for an improved understanding of interesting physical phenomena both in cosmology and in the context of heavy-ion collisions. We discuss the spectrum and bispectrum of these perturbations around a longitudinally expanding fireball after a heavy-ion collision. The time-evolution equations couple the spectrum and bispectrum to each other, as well as to higher-order correlation functions through nonlinear terms. A nontrivial bispectrum is thus always generated, even if absent initially. For initial conditions corresponding to a model of independent sources, we discuss the linear and nonlinear evolution in detail. We show that, if the initial conditions are sufficiently smooth for fluid dynamics to be applicable, the nonlinear effects are relatively small.