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Register a new userTesting AdS early dark energy with Planck, SPTpol and LSS data
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The Hubble tension might be resolved by injecting a new energy component, called Early Dark Energy (EDE), prior to recombination. An Anti-de Sitter (AdS) phase around recombination can make the injected energy decay faster, which thus allows a higher EDE fraction (so larger $H_0$) while prevents degrading the CMB fit. In this work, we test the AdS-EDE model with CMB and Large-Scale Structure (LSS) data. Our CMB dataset consists of low-$ell$ part of Planck TT spectrum and SPTpol polarization and lensing measurements, since this dataset predicts the CMB lensing effect consistent with $Lambda$CDM expectation. Combining it with BAO and Pantheon data, we find the bestfit values $H_0=71.92$ km/s/Mpc and $H_0=73.29$ km/s/Mpc without and with the SH0ES prior, respectively. Including cosmic shear and galaxy clusters data, we have $H_0=71.87$ km/s/Mpc and $S_8=0.785$, i.e. only $1.3sigma$ discrepancy with direct $S_8$ measurement.
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Recently a full-shape analysis of large-scale structure (LSS) data was employed to provide new constraints on a class of Early Dark Energy (EDE) models. In this note, we derive similar constraints on New Early Dark Energy (NEDE) using the publicly available PyBird code, which makes use of the effective field theory of LSS. We study the NEDE base model with the fraction of NEDE and the trigger field mass as two additional parameters allowed to vary freely while making simplifying assumptions about the decaying fluid sector. Including the full-shape analysis of LSS together with measurements of the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO) and supernovae (SN) data, we report $ H_0= 71.2 pm 1.0~textrm{km}, textrm{s}^{-1}, textrm{Mpc}^{-1}$ ($68 %$ C.L.) together with a $simeq 4 , sigma$ evidence for a non-vanishing fraction of NEDE. This is an insignificant change to the value previously found without full-shape LSS data, $ H_0= 71.4 pm 1.0~textrm{km}, textrm{s}^{-1}, textrm{Mpc}^{-1} $ ($68 %$ C.L.). As a result, while the NEDE fit cannot be improved upon the inclusion of additional LSS data, it is also not adversely affected by it, making it compatible with current constraints from LSS data. In fact, we find evidence that the effective field theory of LSS acts in favor of NEDE.
Present-day temperature $T_0$ of cosmic microwave background has been precisely measured by the FIRAS experiment. We identify that the early dark energy (EDE) (non-negligible around matter-radiation equality) scenario can remain compatible with the FIRAS result, while lifting the Hubble constant $H_0$. We perform Monte Carlo Markov chain analysis to confirm our observations. We also present an $alpha$-attractor Anti-de Sitter (AdS) model of EDE, in which the AdS depth is consistently varied in the Monte Carlo Markov chain analysis. We found that our datasets weakly hinted the existence of an AdS phase near recombination with $H_0sim 73$km/s/Mpc at 1$sigma$ region in the best-fit model.
A promising idea to resolve the long standing Hubble tension is to postulate a new subdominant dark-energy-like component in the pre-recombination Universe which is traditionally termed as the Early Dark Energy (EDE). However, as shown in Refs. cite{Hill:2020osr,Ivanov:2020ril} the cosmic microwave background (CMB) and large-scale structure (LSS) data impose tight constraints on this proposal. Here, we revisit these strong bounds considering the Planck CMB temperature anisotropy data at large angular scales and the SPTPol polarization and lensing measurements. As advocated in Ref. cite{Chudaykin:2020acu}, this combined data approach predicts the CMB lensing effect consistent with the $Lambda$CDM expectation and allows one to efficiently probe both large and small angular scales. Combining Planck and SPTPol CMB data with the full-shape BOSS likelihood and information from photometric LSS surveys in the EDE analysis we found for the Hubble constant $H_0=69.79pm0.99,{rm km,s^{-1}Mpc^{-1}}$ and for the EDE fraction $f_{rm EDE}<0.094,(2sigma)$. These bounds obtained without including a local distance ladder measurement of $H_0$ (SH0ES) alleviate the Hubble tension to a $2.5sigma$ level. Including further the SH0ES data we obtain $H_0=71.81pm1.19,{rm km,s^{-1}Mpc^{-1}}$ and $f_{rm EDE}=0.088pm0.034$ in full accordance with SH0ES. We also found that a higher value of $H_0$ does not significantly deteriorate the fit to the LSS data. Overall, the EDE scenario is (though weakly) favoured over $Lambda$CDM even after accounting for unconstrained directions in the cosmological parameter space. We conclude that the large-scale Planck temperature and SPTPol polarization measurements along with LSS data do not rule out the EDE model as a resolution of the Hubble tension. This paper underlines the importance of the CMB lensing effect for robust constraints on the EDE scenario.
We study a class of early dark energy models which has substantial amount of dark energy in the early epoch of the universe. We examine the impact of the early dark energy fluctuations on the growth of structure and the CMB power spectrum in the linear approximation. Furthermore we investigate the influence of the interaction between the early dark energy and the dark matter and its effect on the structure growth and CMB. We finally constrain the early dark energy model parameters and the coupling between dark sectors by confronting to different observations.
The canonical acoustic dark energy model (cADE), which is based on a scalar field with a canonical kinetic term that rapidly converts potential to kinetic energy around matter radiation equality, alleviates the Hubble tension found in $Lambda$CDM. We show that it successfully passes new consistency tests in the CMB damping tail provided by the ACT data, while being increasingly constrained and distinguished from alternate mechanisms by the improved CMB acoustic polarization data from Planck. The best fit cADE model to a suite of cosmological observations, including the SH0ES $H_0$ measurement, has $H_0=70.25$ compared with $68.23$ (km s$^{-1}$ Mpc$^{-1}$) in $Lambda$CDM and a finite cADE component is preferred at the $2.8sigma$ level. The ability to raise $H_0$ is now mainly constrained by the improved Planck acoustic polarization data, which also plays a crucial role in distinguishing cADE from the wider class of early dark energy models. ACT and Planck TE polarization data are currently mildly discrepant in normalization and drive correspondingly different preferences in parameters. Improved constraints on intermediate scale polarization approaching the cosmic variance limit will be an incisive test of the acoustic dynamics of these models and their alternatives.
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