Is the Harrison-Zel’dovich spectrum coming back? ACT preference for<i>ns</i>∼ 1 and its discordance with Planck

Giarè, William; Renzi, Fabrizio; Mena, Olga; Valentino, Eleonora Di; Melchiorri, A.

doi:10.1093/mnras/stad724

Cited by 26 publications

(25 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…See, however, Refs. [343][344][345][346][347] for discussions on the tension between ACT and Planck for what concerns the determination of parameters such as N eff , ω b , and ns.…”

Section: Resultsmentioning

confidence: 99%

Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments

Vagnozzi

2023

Journal of High Energy Astrophysics

View full text Add to dashboard Cite

“…See, however, Refs. [343][344][345][346][347] for discussions on the tension between ACT and Planck for what concerns the determination of parameters such as N eff , ω b , and ns.…”

Section: Resultsmentioning

confidence: 99%

Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments

Vagnozzi

2023

Journal of High Energy Astrophysics

View full text Add to dashboard Cite

“…Therefore, we conclude that IDE cosmologies do not provide a resolution to the discrepancies observed between the two CMB probes. In fact, the tension between ACT and Planck is mainly driven by differences in the value of the spectral index n s and Ω b h 2 [22,88], and both present also in this model, as evident from Table I.…”

Section: Resultsmentioning

confidence: 72%

“…The rest of the cosmological parameters depicted in TableIshow values close to those obtained within the ΛCDM minimal cosmology except for the scalar spectral index, which is close to unity when ACT observations are included in the analyses. We refer the interested reader to the recent work of Ref [88]. for a comprehensive analysis.…”

mentioning

confidence: 99%

A Consistent View of Interacting Dark Energy from Multiple CMB Probes

Zhai¹,

Giarè²,

Bruck³

et al. 2023

Preprint

View full text Add to dashboard Cite

We analyze a cosmological model featuring an interaction between dark energy and dark matter in light of the measurements of the Cosmic Microwave Background released by three independent experiments: the most recent data by the Planck satellite and the Atacama Cosmology Telescope, and WMAP (9-year data). We show that different combinations of the datasets provide similar results, always favoring an interacting dark sector with a 95% CL significance in the majority of the cases. Remarkably, such a preference remains consistent when cross-checked through independent probes, while always yielding a value of the expansion rate H0 consistent with the local distance ladder measurements. We investigate the source of this preference by scrutinizing the angular power spectra of temperature and polarization anisotropies as measured by different experiments.

show abstract

“…The absence of detection of B-mode polarization in the cosmic microwave background [100], which would represent a smoking-gun evidence for inflation, offering valuable information on its underlying micro-physics, presents a major challenge. In addition, the emerging disagreements among independent CMB observations [101][102][103][104][105][106][107][108] often involve inflationary parameters [41,105,106], contributing to the ongoing uncertainty. Thus, with inflation, one of the important cornerstones of modern cosmology, we find ourselves between the known and unknown.…”

Section: Jcap09(2023)019mentioning

confidence: 99%

Inflationary potential as seen from different angles: model compatibility from multiple CMB missions

Giarè,

Pan,

Di Valentino

et al. 2023

J. Cosmol. Astropart. Phys.

Self Cite

View full text Add to dashboard Cite

The cosmic microwave background (CMB) temperature and polarization anisotropies, as observed by independent astronomical missions such as WMAP, Planck, and most recently the Atacama Cosmology Telescope and the South Pole Telescope have played a vital role in accurately constraining cosmological theories and models, establishing cosmic inflation as the most widely accepted theory for describing the physics of the early Universe. However, the absence of a definitive detection of B-mode polarization and the emerging discrepancies among different CMB experiments present a challenge in determining which inflationary models best explain the observed data. In this work, we further explore this difficulty and conduct a case study by analyzing four well-known inflationary potentials in light of the latest CMB temperature and polarization anisotropy measurements and lensing data released by the Planck satellite and the Atacama Cosmology Telescope. Additionally, we incorporate B-modes polarization data from the BICEP/Keck Collaboration, as well as Baryon Acoustic Oscillations and Redshift Space Distortions measurements from BOSS DR12 and eBOSS DR16. We show that the most typical models such as Starobinsky and α-attractors are in disagreement with the Atacama Cosmology Telescope small-scale CMB measurements, particularly when combined with B-modes polarization data. On the other hand, these potentials are in perfect agreement with the Planck measurements at larger angular scales. This dichotomy makes it challenging to identify a single model or a group of models that can be universally considered as the preferred choice based on all available CMB observations.

show abstract

Is the Harrison-Zel’dovich spectrum coming back? ACT preference forns∼ 1 and its discordance with Planck

Cited by 26 publications

References 63 publications

Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments

Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments

A Consistent View of Interacting Dark Energy from Multiple CMB Probes

Inflationary potential as seen from different angles: model compatibility from multiple CMB missions

Contact Info

Product

Resources

About