REVIEW 11 cited by
Revisiting a negative cosmological constant from low-redshift data
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
Signed reviews
abstract
Persisting tensions between high-redshift and low-redshift cosmological observations suggest the dark energy sector of the Universe might be more complex than the positive cosmological constant of the $\Lambda$CDM model. Motivated by string theory, wherein symmetry considerations make consistent AdS backgrounds (\textit (i.e.) maximally symmetric spacetimes with a negative cosmological constant) ubiquitous, we explore a scenario where the dark energy sector consists of two components: a negative cosmological constant, with a dark energy component with equation of state $w_{\phi}$ on top. We test the consistency of the model against low-redshift Baryon Acoustic Oscillation and Type Ia Supernovae distance measurements, assessing two alternative choices of distance anchors: the sound horizon at baryon drag determined by the \textit{Planck} collaboration, and the Hubble constant determined by the SH0ES program. We find no evidence for a negative cosmological constant, and mild indications for an effective phantom dark energy component on top. A model comparison analysis reveals the $\Lambda$CDM model is favoured over our negative cosmological constant model. While our results are inconclusive, should low-redshift tensions persist with future data, it would be worth reconsidering and further refining our toy negative cosmological constant model by considering realistic string constructions.
Forward citations
Cited by 11 Pith papers
-
Hubble tension: the shape wall
Late-time modifications to the expansion history can raise H0 by at most about 2% (conservative) to 3.7% (permissive) if the CMB acoustic scale is fixed.
-
Defocusing dark energy: Raychaudhuri diagnostics beyond $w<-1/3$ and the phantom divide
For sign-changing effective dark energy, smooth negative-to-positive density crossings make ρ+3p and ρ+p the correct diagnostics, give w=p/ρ a universal pole n(1+z†)/3, and force repulsion onset z_rep>z† while ρ<0.
-
Alleviating the Hubble Tension with Smooth Sign-Switching Dark Energy: Full CMB Constraints with DESI and PantheonPlus
Smooth ECDM dark energy remains compatible with Planck+ACT+SPT, DESI DR2 and Pantheon+/SH0ES while alleviating the Hubble tension through a controlled late-time density transition.
-
Background-level reconstruction of scalar-field potentials from dark-energy histories and comparison with analytic potential families
A background reconstruction maps prescribed ρ_de(z) histories to V(φ) and ranks analytic potentials by Bayesian evidence, with exponential preferred for CPL and shifted-tanh for sign-switching targets.
-
Can the universe experience an AdS landscape since matter-radiation equality?
A universe with an AdS (negative cosmological constant) phase at recombination and another at low redshift is compatible with Planck, DESI, Pantheon Plus and SH0ES data, though not preferred by them.
-
Updated Constraints on Omnipotent Dark Energy: A Comprehensive Analysis with CMB and BAO Data
Updated constraints on the DMS20 dark energy model from CMB, BAO, and Pantheon+ data keep it consistent with Lambda CDM while generically producing two phantom-divide crossings; the H0 tension is reduced only with enl...
-
Illustrating the consequences of a misuse of $\sigma_8$ in cosmology
Cosmologists should compare clustering amplitude with the h-independent statistic sigma_12 instead of sigma_8, because sigma_8's smoothing scale shifts with H0 and artificially worsens the growth tension in high-H0 models.
-
Interacting dark energy in the early 2020s: a promising solution to the $H_0$ and cosmic shear tensions
An interacting dark energy model with coupling proportional to the dark energy density alleviates the H0 and S8 tensions in Planck 2018 data but is not preferred once BAO and supernova data are included.
-
Resolving Hubble Tension with Quintom Dark Energy Model
A small negative-density component with equation of state 1/3≤w≤1 can lift H0 from 67.4 to about 74, but the coupled quintom model realizing it either misses the CMB peak or gives H0=68.55.
-
The Lifespan of our Universe
If the axion dark energy model with a negative cosmological constant is the true explanation of DES/DESI data, the universe will end in a big crunch at a total age of about 33 billion years.
-
Cosmology With Low-Redshift Observations: No Signal For New Physics
Combining SN, BAO, lensing, cosmic chronometer, and growth data, the authors find ΛCDM remains the best dark energy model, with H0 and S8 consistent with most early and late universe probes within 2σ.
Discussion (0). Continue with ORCID to comment.