The Physics of Q-balls

Abstract

In this thesis we investigate the stationary properties and formation process of a class of nontopological solitons, namely Q-balls. We explore both the quantum-mechanical and classical stability of Q-balls that appear in polynomial, gravity-mediated and gauge-mediated potentials. By presenting our detailed analytic and numerical results, we show that absolutely stable non-thermal Q-balls may exist in any kinds of the above potentials. The latter two types of potentials are motivated by Affleck-Dine baryogenesis, which is one of the best candidate theories to solve the present baryon asymmetry. By including quantum corrections in the scalar potentials, a naturally formed condensate in a post-inflationary era can be classically unstable and fragment into Q-balls that can be long-lived or decay into the usual baryons/leptons as well as the lightest supersymmeric particles. This scenario naturally provides the baryon asymmetry and the similarity of the energy density between baryons and dark matter in the Universe. Introducing detailed lattice simulations, we argue that the formation, thermalisation and stability of these Q-balls depend on the properties of models involved with supersymmetry breaking.

Ph.D. thesis, University of Nottingham, 156 pages (2009), Advisor: Edmund J. Copeland

References in corpus (20)

• Theory and Numerics of Gravitational Waves from Preheating after Inflation
• A Gravitational Wave Background from Reheating after Hybrid Inflation
• High-energy electron observations by PPB-BETS flight in Antarctica
• Seed perturbations for primordial magnetic fields from MSSM flat directions
• Oscillons and Domain Walls
• Compact Q-balls in the complex signum-Gordon model
• Axino warm dark matter and ${\Omega }_b-{\Omega }_{DM}$ coincidence
• Gravitational waves from the fragmentation of a supersymmetric condensate
• Stability of Q-balls and Catastrophe
• Q-balls in flat potentials
• Supersymmetric Q-balls: A Numerical Study
• Bubbling the False Vacuum Away
• Affleck-Dine condensate, late thermalization and the gravitino problem
• Gravitational Waves from the Non-Perturbative Decay of Condensates along Supersymmetric Flat Directions
• The ground states of baryoleptonic Q-balls in supersymmetric models
• Enhanced Dark Matter Annihilation Rate for Positron and Electron Excesses from Q-ball Decay
• Supermassive gravitinos, dark matter, leptogenesis and flat direction baryogenesis
• Astrophage of neutron stars from supersymmetric dark matter Q-balls
• Resonant particle production in branonium
• Properties of Q-ball dark matter: moving away from flat directions