Evidence for universal flow and characteristics of early time thermalization in a scalar field model for heavy ion collisions

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Carrington, Margaret E., Cowie, Wade N., Kunstatter, Gabor, Phillips, Christopher D.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916196140449792
author Carrington, Margaret E.
Cowie, Wade N.
Kunstatter, Gabor
Phillips, Christopher D.
author_facet Carrington, Margaret E.
Cowie, Wade N.
Kunstatter, Gabor
Phillips, Christopher D.
contents We study numerically the evolution of an expanding strongly self-coupled real scalar field. We use a conformally invariant action that gives a traceless energy-momentum tensor and is better suited to model the early time behaviour of a system such as QCD, whose action is also conformally invariant.We consider asymmetric initial conditions and observe that when the system is initialized with non-zero spatial eccentricity, the eccentricity decreases and the elliptic flow coefficient increases. We look at a measure of transverse pressure asymmetry that has been shown to behave similarly to the elliptic flow coefficient in hydrodynamic systems and show that in our system their behaviour is strikingly similar. We show that the derivative of the transverse velocity is proportional to the gradient of the energy in Milne coordinates and argue that this result means that transverse velocity initially develops in the same way that it does in hydrodynamic systems. We conclude that some aspects of the early onset of hydrodynamic behaviour that has been observed in quark-gluon plasmas are seen in our numerical simulation of strongly coupled scalar fields.
format Preprint
id arxiv_https___arxiv_org_abs_2404_04378
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Evidence for universal flow and characteristics of early time thermalization in a scalar field model for heavy ion collisions
Carrington, Margaret E.
Cowie, Wade N.
Kunstatter, Gabor
Phillips, Christopher D.
High Energy Physics - Theory
We study numerically the evolution of an expanding strongly self-coupled real scalar field. We use a conformally invariant action that gives a traceless energy-momentum tensor and is better suited to model the early time behaviour of a system such as QCD, whose action is also conformally invariant.We consider asymmetric initial conditions and observe that when the system is initialized with non-zero spatial eccentricity, the eccentricity decreases and the elliptic flow coefficient increases. We look at a measure of transverse pressure asymmetry that has been shown to behave similarly to the elliptic flow coefficient in hydrodynamic systems and show that in our system their behaviour is strikingly similar. We show that the derivative of the transverse velocity is proportional to the gradient of the energy in Milne coordinates and argue that this result means that transverse velocity initially develops in the same way that it does in hydrodynamic systems. We conclude that some aspects of the early onset of hydrodynamic behaviour that has been observed in quark-gluon plasmas are seen in our numerical simulation of strongly coupled scalar fields.
title Evidence for universal flow and characteristics of early time thermalization in a scalar field model for heavy ion collisions
topic High Energy Physics - Theory
url https://arxiv.org/abs/2404.04378