Circular polarization of primordial gravitational waves in string-inspired inflationary cosmology
- Department of Physics, Kyoto University, Kyoto 606-8501 (Japan)
- Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada)
We study a mechanism to produce the circular polarization of primordial gravitational waves. The circular polarization is generated during the superinflation driven by the Gauss-Bonnet term in the string-inspired cosmology. The instability in the tensor mode caused by the Gauss-Bonnet term and the parity violation due to the gravitational Chern-Simons term are the essential ingredients of the mechanism. We also discuss detectability of the produced circular polarization of gravitational waves. It turns out that the simple model of single-field inflation contradicts cosmic microwave background (CMB) observations. To circumvent this difficulty, we propose a two-field inflation model. In this two-field model, the circular polarization of gravitational waves is created in the frequency range designed by the big-bang observer (BBO) or the deci-hertz gravitational-wave observatory (DECIGO)
- OSTI ID:
- 21035814
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 77, Issue 2; Other Information: DOI: 10.1103/PhysRevD.77.023526; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
Probing the size of extra dimensions with gravitational wave astronomy
Slow-roll inflation with the Gauss-Bonnet and Chern-Simons corrections