Vector and tensor perturbations in Horava-Lifshitz cosmology - High Energy Physics - TheoryReportar como inadecuado




Vector and tensor perturbations in Horava-Lifshitz cosmology - High Energy Physics - Theory - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: We study cosmological vector and tensor perturbations in Horava-Lifshitzgravity, adopting the most general Sotiriou-Visser-Weinfurtner generalizationwithout the detailed balance but with projectability condition. After derivingthe general formulas in a flat FRW background, we find that the vectorperturbations are identical to those given in general relativity. This is truealso in the non-flat cases. For the tensor perturbations, high orderderivatives of the curvatures produce effectively an anisotropic stress, whichcould have significant efforts on the high-frequency modes of gravitationalwaves, while for the low-frenquency modes, the efforts are negligible. Thepower spectrum is scale-invariant in the UV regime, because of the particulardispersion relations. But, due to lower-order corrections, it will eventuallyreduce to that given in GR in the IR limit. Applying the general formulas tothe de Sitter and power-law backgrounds, we calculate the power spectrum andindex, using the uniform approximations, and obtain their analyticalexpressions in both cases.



Autor: Anzhong Wang

Fuente: https://arxiv.org/







Documentos relacionados