Cosmic bubble and domain wall instabilities I: parametric amplification of linear fluctuations
TLDR
In this paper, the authors consider the evolution of linear fluctuations around highly symmetric though inhomogeneous backgrounds and demonstrate that a large degree of asymmetry develops over time from tiny fluctuations superposed upon planar and SO(2,1) symmetric backgrounds.Abstract:
This is the first paper in a series where we study collisions of nucleated bubbles taking into account the effects of small initial (quantum) fluctuations in a fully 3+1-dimensional setting. In this paper, we consider the evolution of linear fluctuations around highly symmetric though inhomogeneous backgrounds. We demonstrate that a large degree of asymmetry develops over time from tiny fluctuations superposed upon planar and SO(2,1) symmetric backgrounds. These fluctuations arise from zero-point vacuum oscillations, so excluding them by enforcing a spatial symmetry is inconsistent in a quantum treatment. We consider the limit of two colliding planar walls, with fluctuation mode functions characterized by the wavenumber transverse to the collision direction and a longitudinal shape along the collision direction $x$, which we solve for. Initially, the fluctuations obey a linear wave equation with a time- and space-dependent mass $m_{eff}(x,t)$. When the walls collide multiple times, $m_{eff}$ oscillates in time. We use Floquet theory to study the fluctuations and generalize techniques familiar from preheating to the case with many coupled degrees of freedom. This inhomogeneous case has bands of unstable transverse wavenumbers $k_\perp$ with exponentially growing mode functions. From the detailed spatial structure of the mode functions in $x$, we identify both broad and narrow parametric resonance generalizations of the homogeneous $m_{eff}(t)$ case of preheating. The unstable $k_\perp$ modes are longitudinally localized, yet can be described as quasiparticles in the Bogoliubov sense. We define an effective occupation number to show they are created in bursts for the case of well-defined collisions in the background. The transverse-longitudinal coupling accompanying nonlinearity radically breaks this localized particle description, with nonseparable 3D modes arising.read more
Citations
More filters
Journal ArticleDOI
Cosmic phase transitions: their applications and experimental signatures
Anupam Mazumdar,Graham White +1 more
TL;DR: In this article, the authors review different types of phase transitions that can appear in our cosmic history, and their applications and experimental signatures in particular in the context of exciting gravitational waves, which could be potentially be constrained by LIGO/VIRGO, Kagra, and eLISA.
Journal ArticleDOI
Gravitational waves from vacuum first-order phase transitions: From the envelope to the lattice
TL;DR: In this paper, a power law for the gravitational wave power spectrum at high wave number which falls off as ${k}^{\ensuremath{-}15}$ rather than the ${k √ √ 1}$ produced by the envelope approximation was found.
Journal ArticleDOI
Gravitational waves from vacuum first-order phase transitions. II. From thin to thick walls
Daniel Cutting,Elba Granados Escartin,Mark Hindmarsh,Mark Hindmarsh,David J. Weir,David J. Weir +5 more
TL;DR: In this article, the authors studied the possibility of observing the gravitational wave spectrum created in a first-order phase transition (in beyond the standard model theories) in upcoming space-based detectors like LISA.
Journal ArticleDOI
New Semiclassical Picture of Vacuum Decay.
Jonathan Braden,Matthew C. Johnson,Hiranya V. Peiris,Hiranya V. Peiris,Andrew Pontzen,Silke Weinfurtner +5 more
TL;DR: In this paper, a real-time model of vacuum decay via bubble formation was proposed. But this model does not rely on classically forbidden tunneling paths and does not provide a realtime description of the decay process.
Journal ArticleDOI
Suppression of two-bounce windows in kink-antikink collisions
TL;DR: In this article, the authors considered a class of topological defects with a deformed ϕ 4 kink structure whose stability analysis leads to a Schrodinger-like equation with a zero-mode and at least one vibrational (shape) mode.
References
More filters
Journal ArticleDOI
Large Mass Hierarchy from a Small Extra Dimension
TL;DR: In this paper, the weak scale is generated from the Planck scale through an exponential hierarchy, but this exponential arises not from gauge interactions but from the background metric, which is a slice of spacetime.
Journal ArticleDOI
Construction of higher order symplectic integrators
TL;DR: For Hamiltonian systems of the form H = T(p)+V(q) a method was shown to construct explicit and time reversible symplectic integrators of higher order as discussed by the authors.
Journal ArticleDOI
Fate of the false vacuum: Semiclassical theory
TL;DR: In this article, the decay of a false vacuum in a single scalar field with nonderivative interactions is studied. But the decay is not restricted to the case of singular fields.
Journal ArticleDOI
Towards the theory of reheating after inflation
TL;DR: In this paper, the authors investigated a simple model of a massive inflaton field coupled to another scalar field with the interaction term, and developed the theory of preheating taking into account the expansion of the universe and back reaction of produced particles, including the effects of rescattering.