Change search
ReferencesLink to record
Permanent link

Direct link
Harmonic generation of gravitational wave induced Alfven waves
Umeå University, Faculty of Science and Technology, Department of Physics.
Umeå University, Faculty of Science and Technology, Department of Physics.
2008 (English)In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 77, no 2, 024050-024050-6 p.Article in journal (Refereed) Published
Abstract [en]

Here we consider the nonlinear evolution of Alfvén waves that have been excited by gravitational waves from merging binary pulsars. We derive a wave equation for strongly nonlinear and dispersive Alfvén waves. Because of the weak dispersion of the Alfvén waves, significant wave steepening can occur, which in turn implies strong harmonic generation. We find that the harmonic generation is saturated due to dispersive effects, and use this to estimate the resulting spectrum. Finally we discuss the possibility of observing the above process.

Place, publisher, year, edition, pages
American Physical Society , 2008. Vol. 77, no 2, 024050-024050-6 p.
URN: urn:nbn:se:umu:diva-10375DOI: 10.1103/PhysRevD.77.024050OAI: diva2:150046
Available from: 2008-08-27 Created: 2008-08-27 Last updated: 2010-12-14Bibliographically approved
In thesis
1. Gravitational perturbations in plasmas and cosmology
Open this publication in new window or tab >>Gravitational perturbations in plasmas and cosmology
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Gravitational perturbations can be in the form of scalars, vectors or tensors. This thesis focuses on the evolution of scalar perturbations in cosmology, and interactions between tensor perturbations, in the form of gravitational waves, and plasma waves.

The gravitational waves studied in this thesis are assumed to have small amplitudes and wavelengths much shorter than the background length scale, allowing for the assumption of a flat background metric. Interactions between gravitational waves and plasmas are described by the Einstein-Maxwell-Vlasov, or the Einstein-Maxwell-fluid equations, depending on the level of detail required. Using such models, linear wave excitation of various waves by gravitational waves in astrophysical plasmas are studied, with a focus on resonance effects. Furthermore, the influence of strong magnetic field quantum electrodynamics, leading to detuning of the gravitational wave-electromagnetic wave resonances, is considered. Various nonlinear phenomena, including parametric excitation and wave steepening are also studied in different astrophysical settings.

In cosmology the evolution of gravitational perturbations are of interest in processes such as structure formation and generation of large scale magnetic fields. Here, the growth of density perturbations in Kantowski-Sachs cosmologies with positive cosmological constant is studied.

Place, publisher, year, edition, pages
Umeå: Institutionen för Fysik, 2010. 48 p.
general relativity, cosmology, gravitational waves, plasma, electromagnetic waves, nonlinear waves
National Category
Fusion, Plasma and Space Physics Other Physics Topics Astronomy, Astrophysics and Cosmology
Research subject
Theoretical Physics
urn:nbn:se:umu:diva-38387 (URN)978-91-7459-125-5 (ISBN)
Public defence
2011-01-04, Naturvetarhuset, N430, Umeå Universitet, Umeå, 13:00 (English)
Available from: 2010-12-14 Created: 2010-12-10 Last updated: 2010-12-14Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Forsberg, MatsBrodin, Gert
By organisation
Department of Physics
In the same journal
Physical Review D. Particles and fields

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 41 hits
ReferencesLink to record
Permanent link

Direct link