Hints of early dark energy in Planck , SPT, and ACT data: New physics or systematics?

Abstract

H 0 and the full Planck power spectra, within the EDE model one obtains a non-zero fraction of the total energy density in EDE at the critical redshift, f EDE (z c ) = 0.108 +0.035 −0.028 , with a corresponding Hubble parameter H 0 = 71.5 ± 1.2 km/s/Mpc [30] (adding supernovae (SNe) and baryon acoustic oscillation 'standard ruler' (BAO) data leads to insignificant shifts). Without the SH 0 ES prior, one has instead an upper bound of the form f EDE (z c ) < 0.088 at 95% confidence level (CL) and H 0 = 68.29 +0.75 −1.3 km/s/Mpc [30,31]. 2 Recent analyses of EDE using data from the Atacama Cosmology Telescope's fourth data release (ACT DR4) [34] alone have shown a slight (∼ 2.2σ) preference for the presence of an EDE component with a fraction f EDE (z c ) ∼ 0.15 and H 0 ∼ 74 km/Mpc/s [35,36]. Interestingly, the inclusion of large-scale CMB temperature measurements by the Wilkinson Microwave Anisotropy Probe (WMAP) [37] or the Planck satellite [2] restricted to the WMAP multipole range increases the preference to ∼ 3σ. A similar analysis using the third generation South Pole Telescope 2018 (SPT-3G) data [38] was presented in Ref. [39] (see also Refs. [28,29] for previous studies using SPTpol). There is no evidence for EDE over ΛCDM using SPT-3G alone or when combined with the Planck temperature power spectrum restricted to < 650, giving the marginalized constraint f EDE (z c ) < 0.2 at 95% CL in the latter case. Combining ACT DR4 and/or SPT-3G with the full Planck CMB power spectra returns an upper limit on f EDE (z c ), albeit less restrictive than for Planck alone.In Refs. [35,36] it was argued that the ACT DR4 preference for EDE is mainly driven by a feature in the ACT DR4 EE power spectrum around ∼ 500 when ACT DR4 is considered alone, with an additional broadlydistributed contribution from the TE spectrum when in combination with restricted Planck TT data ( < 650 or < 1060). Ref.[36] also considered the role of Planck polarization data, finding that the evidence for a nonzero f EDE (z c ) and an increased H 0 persists, as long as the Planck TT spectrum is restricted to < 1060.Building on these previous studies, the work presented here explores in more detail how the evidence for EDE using data from ACT DR4, SPT-3G or both data sets is impacted by the inclusion of the more precise intermediatescale (O( ) = 100) polarization measurements by Planck. We test the robustness of the results to changes in the Planck TE polarization efficiency and the dust contamination amplitudes in Planck EE. We also further investigate the role of Planck high-TT data as well as that of several non-CMB probes.This paper is organized as follows. In Section II we briefly summarize the numerical setup and cosmological data sets used in our analysis. In Section III we present

DE Models with Combined H0 · rd from BAO and CMB Dataset and Friends

“…There are many Dark Energy (DE) parametrisations [20][21][22][23] that can be used in the search for deviations from the cosmological constant, Λ. Some of them fall in the group of Early Dark Energy models [24][25][26][27][28], which modify physics of the early universe. Others modify the late-time universe physics such as in the Phantom Dark Energy [29,30] models, Emergent Dark Energy [31,32], or add interaction in the DE sector as in the Interacting Dark Energy [33][34][35], or add exotic species or scalar fields [36][37][38][39][40].…”

Return of Harrison-Zeldovich spectrum in light of recent cosmological tensions

“…which seems to suggest that the complete resolution H 0 ∼ 73 km/s/Mpc of Hubble tension is pointing towards a scale-invariant Harrison-Zeldovich spectrum, i.e.n s = 1 ( Here n s = 1 refers to a very small region near n s = 1, contrasted with Planck result n s = 0.965 ± 0.004 on ΛCDM model), see also 18 . Recent large-scale structure observations is actually not conflicted with n s = 1 19,20 .…”

“…As a supplement, we also show the results with base1000+ACT+SPT dataset, which is the combination of base dataset with ACT DR4 39 and SPT-3G Y1 40 observations, while the small scale part ( > 1000) of Planck TT is cut off, as in Refs. 17,18,41 . And it has similar conclusion.…”

A reanalysis of the latest SH0ES data for $H_0$: Effects of new degrees of freedom on the Hubble tension

“…Thus, early time sound horizon models introduce new degrees of freedom at the time just before recombination (e.g. early dark energy [31,[35][36][37][38][39][40][41][42][43][44][45][46][47], radiation [48][49][50][51] or modified gravity [52][53][54][55][56][57]) to change the expansion rate at that time and thus decrease the sound horizon scale r s (early time distance calibrator) to increase H 0 , which is degenerate with r s , to a value consistent with local measurements.…”

“…Thus, a compelling and full resolution of the Hubble tension may require multiple (or other) modifications beyond the scale of the sound horizon predicted by ΛCDM cosmology. Even though these models are severely constrained by various cosmological observables, they currently constitute the most widely studied class of models [37][38][39]45,72,73].…”