REVIEW 10 cited by
The Sigma-8 Tension is a Drag
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
abstract
Measurements of weak gravitational lensing at low redshifts ($z\lesssim 0.5-1$), quantified by the parameter $S_8$, favor weaker matter clustering than that expected from the standard $\Lambda$CDM cosmological model with parameters determined by cosmic microwave background (CMB) measurements. However, the amplitude of matter clustering at higher redshifts, as probed by lensing of the CMB, is consistent with $\Lambda$CDM. This apparent paradox suggests a connection between the $S_8$ tension and the transition from matter to dark-energy domination. Here we show that the tension can be resolved by introducing a friction between dark matter and dark energy without altering the tightly constrained expansion history. The low-$S_8$ measurements favor (at $\gtrsim3\sigma$, in this one parameter model) a non-zero drag leading to a suppression of low-redshift power right around the transition from matter to dark-energy domination. We suggest ways to further probe the scenario.
Forward citations
Cited by 10 Pith papers
-
A Sequentially-Valid Reanalysis of DESI's Dynamical Dark Energy Signal
An anytime-valid e-process reanalysis shows DESI's dynamical dark energy evidence is a fragile LRG2-bin, specification-dependent signal that does not survive a trials correction.
-
Disentangling Similarity and Relatedness in Topic Models
Topic models lie on a spectrum from thematic-relatedness-rich to similarity-rich, and that position predicts which downstream tasks they handle well.
-
Phantom-divide crossing and suppressed structure growth in kinetically braided dark energy with momentum exchange
A linearly stable kinetic-braiding dark-energy model with CDM momentum exchange realizes upward phantom-divide crossing and weak CDM gravitational clustering, altering matter and CMB spectra.
-
Decaying Dark Matter Halo Abundance from a Revised Spherical Collapse Model
A mass-dependent collapse threshold from a revised spherical collapse model predicts the decaying-dark-matter halo mass function, matching N-body simulations at z≈1 and for mild kicks at z=0.
-
Revisiting observational constraints on coupled exponential quintessence with energy and momentum transfers: degeneracy with massive neutrinos
Allowing the neutrino mass to vary removes the 2σ evidence for momentum transfer between dark energy and dark matter in coupled quintessence, via a degeneracy with the energy-exchange coupling.
-
Dark sector interactions in the $w \rightarrow -1$ limit: velocity locking in pure momentum exchange models
In momentum-exchange dark sector models, the suppression of matter clustering moves to smaller scales as w→−1 due to velocity locking, and ignoring DE perturbations erases this effect.
-
A frequentist view on the two-body decaying dark matter model
A frequentist reanalysis of Planck and KiDS-1000 data shows that a two-body decaying dark matter model can produce S8 values consistent with weak lensing surveys, and that prior choices dominated earlier Bayesian exclusions.
-
Signatures of Modified Gravity on Linear Scales in a Dynamical Dark Energy Background
Using Planck, DESI, supernovae, and redshift-space distortions, the authors infer that modified gravity, if present, must act only below ~30 Mpc and cannot modify the large scales previously considered.
-
Cosmo-Learn: code for learning cosmology using different methods and mock data
An open-source toolkit that simulates late-universe cosmological observations and benchmarks MCMC, genetic algorithms, Gaussian processes, Bayesian ridge regression, and neural networks in one pipeline.
-
The Hubble tension: A decade review
Pure early or late fixes to the Hubble tension are tightly constrained; remaining options are combined early-late interacting dark energy or new physics at the local-to-homogeneous transition.
Discussion (0). Sign in to comment.