REVIEW 6 cited by
The axis of systematic bias in SN~Ia cosmology and implications for DESI 2024 results
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
Relative distances between a high-redshift sample of Type Ia supernovae (SNe~Ia), anchored to a low-redshift sample, have been instrumental in drawing insights on the nature of the dark energy driving the accelerated expansion of the universe. A combination (hereafter called SBC) of the SNe~Ia with baryon acoustic oscillations (BAO) from the Dark Energy Spectroscopic Instrument (DESI) and the cosmic microwave background (CMB) recently indicated deviations from the standard interpretation of dark energy as a cosmological constant. In this paper, we analyse various systematic uncertainties in the distance measurement of SNe~Ia and their impact on the inferred dark energy properties in the canonical Chevallier-Polarski-Linder (CPL) model. We model systematic effects like photometric calibration, progenitor and dust evolution, and uncertainty in the galactic extinction law. We find that all the dominant systematic errors shift the dark energy inference towards the DESI 2024 results from an underlying $\Lambda$CDM cosmology. A small change in the calibration, and change in the Milky Way dust, can give rise to systematic-driven shifts on $w_0$-$w_a$ constraints, comparable to the deviation reported from the DESI 2024 results. We forecast that the systematic uncertainties can shift the inference of $w_0-w_a$ by a few times the error ellipse for future low- and high-$z$ SN~Ia compilations and hence, it is critical to circumvent them to robustly test for deviations from $\Lambda$. A slider and visualisation tool for quantifying the impact of systematic effects on the fitted cosmological parameters is publicly available at: https://github.com/sdhawan21/DEslider.git
Forward citations
Cited by 6 Pith papers
-
A Simulation Based Inference Approach to Modelling of Type Ia Supernova Populations
A simulation-based inference pipeline (Stjörnumál) fits SN Ia dust and intrinsic scatter models to DES 5-year data, enabling fast Bayesian model comparison across seven SN Ia population models.
-
Implications for dark energy of cosmic transparency in light of DESI data
No deviation found from the distance duality relation in combined DESI, CMB, and supernova data, ruling out dimming as an explanation of the Hubble tension.
-
Void spin distribution as a powerful probe of $\sigma_{8}$
Void spin distributions, fitted by a generalized Gamma function, are shown in simulations to vary sensitively with sigma8 but not with Omega_cdm h^2, neutrino mass, or dark energy equation of state, offering a new deg...
-
Robustness of dark energy phenomenology across different parameterizations
The viability of minimally and non-minimally coupled quintessence models is robust across CPL, JBP, BA, and EXP parameterizations, with all four reproducing the models' predicted observables accurately.
-
The DESI DR1/DR2 evidence for dynamical dark energy is biased by low-redshift supernovae
The DESI dynamical dark energy preference drops below 2 sigma after correcting a 0.043 mag intercept discrepancy in the low-redshift supernovae of DESY5.
-
An overview of what current data can (and cannot yet) say about evolving dark energy
The apparent preference for evolving dark energy depends strongly on which supernova catalog and which BAO survey are used, and is not robust across all independent data combinations.
Discussion (0). Continue with ORCID to comment.