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arXiv · 1008.4866

Estimating the amount of vorticity generated by cosmological perturbations in the early universe

Adam J. Christopherson·Karim A. Malik·David R. Matravers
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Abstract

We estimate the amount of vorticity generated at second order in cosmological perturbation theory from the coupling between first order energy density and non-adiabatic pressure, or entropy, perturbations. Assuming power law input spectra for the source terms, and working in a radiation background, we calculate the wave number dependence of the vorticity power spectrum and its amplitude. We show that the vorticity generated by this mechanism is non-negligible on small scales, and hence should be taken into consideration in current and future CMB experiments.

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Adam J. Christopherson, Karim A. Malik, David R. Matravers. 2010-10-19. Estimating the amount of vorticity generated by cosmological perturbations in the early universe. https://doi.org/10.1103/physrevd.83.123512

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