Phase transitions in the Universe (original) (raw)

Phase Transitions in the Universe 1

1998

During the past two decades, cosmologists turned to particle physics in order to explore the physics of the very early Universe. The main link between the physics of the smallest and largest structures in the Universe is the idea of spontaneous symmetry breaking, familiar from condensed matter physics. Implementing this mechanism into cosmology leads to the interesting possibility that phase transitions related to the breaking of symmetries in high energy particle physics took place during the early history of the Universe. These cosmological phase transitions may help us 1 Invited article for Contemporary Physics. NSF Presidential Faculty Fellow. email: gleiser@dartmouth.edu Permanent address.

The Current Universe As A Phase Transition, Part 2

This paper continues the exploration of the idea of the current universe as a phase transition that I began in the first paper of the same name. However, in this second part, I expand and refine the idea and include many more relevant connections to existing research in various branches of physics. I also look in detail into the possibilitiy of experimentally verifying some of the key aspects of the phase transition model. This paper closes with a general reflection on the issue of observation with connections to other traditions and ways of conceptualizing physical reality.

The Big Bang as a Phase Transition

International Journal of Modern Physics A, 2005

We study a five-dimensional cosmological model, which suggests that the universe began as a discontinuity in a scalar (Higgs-type) field, or alternatively as a conventional four-dimensional phase transition.

The Current Universe as a Phase Transition

This paper introduces the novel idea that the entire physical universe is a phase transition related to a more fundamental substance that changes through a transition zone that we know as quantum potential.

Smooth phase transitions in the early universe

We apply a quadratic teleparallel torsion scalar of the f (T) = T + αT 2 field equations to the flat FRW model. We assume two perfect fluid components, the matter component has a fixed equation of state (EoS), while the torsion component has a dynamical EoS. We obtain an effective scale factor allowing an early stage of an inflationary vacuum, while it pushes the inflation to end naturally at later stage turning the universe to a matter dominant phase. The model represents an alternative to inflation models. However, it does not require slow roll conditions to end the inflation phase. We perform a standard cosmological study to examine the cosmic evolution. In addition, we study the effective EoS. The study shows consistent results confirming a smooth phase transition from inflation to matter dominant universe. We consider the case when the torsion is made of a scalar field. This treatment enables us to study the quadratic effect of f (T) on the potential patterns of the scalar fiel...

First order phase transitions in cosmology

New Astronomy, 1999

We review the observable effects produced by phase transitions occurring along with inflation. Firstly, we present a model which is able to generate a locally open universe as the result of a very early phase transition peaked at a precise epoch. Then, we show how the same model can produce primordial voids on the large scale structure, able to imprint in an observable way the microwave background. Finally, we speculate on the possibility of merging the two mechanisms in the same process.

Phase Transitions in the Early Universe: Theory and Observations

2001

A Series presenting the resuits of scientific meetings supported under the NATO Science Programme. The Series is published by IOS Press, Amsterdam, and Kluwer Academic Publishers in conjunction with the NATO Scientific Affairs Division The NATO Science Series continues the series of books published formerly as the NATO ASI Series. The NATO Science Programme offers support for collaboration in civil science between scientists of countries of the Euro-Atlantic Partnership Council. The types of scientific meeting generally supported are "Advanced Study Institutes" and "Advanced Research Workshops", although other types of meeting are supported from time to time. The NATO Science Series collects together the results of these meetings. The meetings are co-organized bij scientists from NATO countries and scientists from NATO's Partner countries-countries of the CIS and Central and Eastern Europe. Advanced Study Institutes are high-level tutorial courses offering in-depth study of latest advances in afield. Advanced Research Workshops are expert meetings aimed at critical assessment of a field, and identification of directions for future action.

Symmetry structure and phase transitions

Pramana, 2003

We study chiral symmetry structure at finite density and temperature in the presence of external magnetic field and gravity, a situation relevant in the early Universe and in the core of compact stars. We then investigate the dynamical evolution of phase transition in the expanding early Universe and possible formation of quark nuggets and their survival.