Testing dark energy after pre-recombination early dark energy

Hao Wang; Yun-Song Piao

doi:10.1016/j.physletb.2022.137244

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arXiv · 2201.07079

Testing dark energy after pre-recombination early dark energy

Hao Wang·Yun-Song Piao

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Abstract

In the studies on pre-recombination early dark energy (EDE), the evolution of Universe after recombination is usually regarded as $ΛCDM$-like, which corresponds that the equation of state of dark energy responsible for current accelerated expansion is $w=-1$. However, in realistic models, $w$ might be evolving. We consider the parametrizations of $w$ with respect to the redshift $z$ in Axion-like EDE and AdS-EDE models, respectively. We performed the Monte Carlo Markov chain analysis with recent cosmological data, and found that the bestfit $w(z)$ is compatible with $w_0=-1,w_a=0$ (the cosmological constant) and the evolution of $w$ is only marginally favored, which so has little effect on lifting the bestfit value of ${H_0}$.

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Hao Wang, Yun-Song Piao. 2022-08-31. Testing dark energy after pre-recombination early dark energy. https://doi.org/10.1016/j.physletb.2022.137244

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