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arXiv · 2012.07602

Evolution of perturbation and power spectrum in a two-component ultralight axionic universe

Yi-Hsiung Hsu·Tzihong Chiueh
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Abstract

The evolution of cosmic perturbations in a two-component ultralight axionic universe is investigated. We present the first spectral computation of perturbations in multi-component universes. A particular case composed of light extreme axions and free massive particles offers a possibility for the formation of very high-redshift massive galaxies, which are typically required to host massive early quasars. Our computation retains the information of perturbed velocities for individual axion components, opening a new avenue for setting up initial conditions for future axion dark matter simulations.

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Yi-Hsiung Hsu, Tzihong Chiueh. 2020-12-14. Evolution of perturbation and power spectrum in a two-component ultralight axionic universe. https://doi.org/10.1103/physrevd.103.103516

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