Gravitational Waves from Mesoscopic Dynamics of the Extra Dimensions

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Recent models which describe our world as a brane embedded in a higher dimensional space introduce new geometrical degrees of freedom: the shape and/or size of the extra dimensions, and the position of the brane. These modes can be coherently excited by symmetry breaking in the early universe even on ``mesoscopic'' scales as large as 1 mm, leading to detectable gravitational radiation. Two sources are described: relativistic turbulence caused by a first-order transition of a radion potential, and Kibble excitation of Nambu-Goldstone modes of brane displacement. Characteristic scales and spectral properties are estimated and the prospects for observation by LISA are discussed. Extra dimensions with scale between 10 \AA and 1 mm, which enter the 3+1-D era at cosmic temperatures between 1 and 1000 TeV, produce backgrounds with energy peaked at observed frequencies in the LISA band, between \(10^{-1}\) and \(10^{-4}\) Hz. The background is detectable above instrument and astrophysical foregrounds if initial metric perturbations are excited to a fractional amplitude of \(10^{-3}\) or more, a likely outcome for the Nambu-Goldstone excitations.

Related collections

Most cited references 11

Record: found
Abstract: found
Article: found

Is Open Access

A Large Mass Hierarchy from a Small Extra Dimension

Raman Sundrum, Lisa Randall (1999)

We propose a new higher-dimensional mechanism for solving the Hierarchy Problem. The Weak scale is generated from a large scale of order the Planck scale through an exponential hierarchy. However, this exponential arises not from gauge interactions but from the background metric (which is a slice of AdS_5 spacetime). This mechanism relies on the existence of only a single additional dimension. We demonstrate a simple explicit example of this mechanism with two three-branes, one of which contains the Standard Model fields. The experimental consequences of this scenario are new and dramatic. There are fundamental spin-2 excitations with mass of weak scale order, which are coupled with weak scale as opposed to gravitational strength to the standard model particles. The phenomenology of these models is quite distinct from that of large extra dimension scenarios; none of the current constraints on theories with very large extra dimensions apply.

0 comments Cited 1511 times – based on 0 reviews

Preprint

     Review now

Bookmark

Record: found
Abstract: not found
Article: not found

Fate of the false vacuum: Semiclassical theory

Sidney Coleman (1977)

0 comments Cited 749 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: found

Is Open Access

Gravitational Radiation from First-Order Phase Transitions

Michael Turner, Marc Kamionkowski, Arthur Kosowsky (1993)

We consider the stochastic background of gravity waves produced by first-order cosmological phase transitions from two types of sources: colliding bubbles and hydrodynamic turbulence. First we discuss the fluid mechanics of relativistic spherical combustion. We then numerically collide many bubbles expanding at a velocity \(v\) and calculate the resulting spectrum of gravitational radiation in the linearized gravity approximation. Our results are expressed as simple functions of the mean bubble separation, the bubble expansion velocity, the latent heat, and the efficiency of converting latent heat to kinetic energy of the bubble walls. We also estimate the gravity waves produced by a Kolmogoroff spectrum of turbulence and find that the characteristic amplitude of gravity waves produced is comparable to that from bubble collisions. Finally, we apply these results to the electroweak transition. Using the one-loop effective potential for the minimal electroweak model, the characteristic amplitude of gravity waves produced is \(h\simeq 1.5\times 10^{-27}\) at a characteristic frequency of \(4.1\times 10^{-3} \,\rm Hz\) corresponding to \(\Omega \sim10^{-22}\) in gravity waves, far too small for detection. Gravity waves from more strongly first-order phase transitions, including the electroweak transition in non-minimal models, have better prospects for detection, though probably not by LIGO.