Novel geometrical test of cosmological expansion from photometric data

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Touzeau, David, Bernardeau, Francis, Benabed, Karim, Codis, Sandrine
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866908986267140096
author Touzeau, David
Bernardeau, Francis
Benabed, Karim
Codis, Sandrine
author_facet Touzeau, David
Bernardeau, Francis
Benabed, Karim
Codis, Sandrine
contents In tomographic cosmic-shear observations, the BNT (Bernardeau, Nishimichi, Taruya) transform, Bernardeau et al. (2014), allows to build weak lensing transformed maps for which the contribution from low redshift lenses is nulled. As this transformation depends specifically on the expansion rate of the Universe but is independent of the matter distribution properties, it can be leveraged to extract information from large-scale structure probes at arbitrary non-linear scales, providing constraints on cosmological background evolution. We demonstrate this by proposing a specific null test for stage IV weak lensing projects. Using a Fisher matrix analysis and parameter sampling, we show that this approach can substantially enhance constraints on the dark energy equation of state. Notably, we find that shape noise currently limits this method's effectiveness making significant improvement possible in future designs. A detailed analysis of our null test in the context of the Euclid mission is presented in a companion paper Touzeau et al. (2025).
format Preprint
id arxiv_https___arxiv_org_abs_2502_02243
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Novel geometrical test of cosmological expansion from photometric data
Touzeau, David
Bernardeau, Francis
Benabed, Karim
Codis, Sandrine
Cosmology and Nongalactic Astrophysics
In tomographic cosmic-shear observations, the BNT (Bernardeau, Nishimichi, Taruya) transform, Bernardeau et al. (2014), allows to build weak lensing transformed maps for which the contribution from low redshift lenses is nulled. As this transformation depends specifically on the expansion rate of the Universe but is independent of the matter distribution properties, it can be leveraged to extract information from large-scale structure probes at arbitrary non-linear scales, providing constraints on cosmological background evolution. We demonstrate this by proposing a specific null test for stage IV weak lensing projects. Using a Fisher matrix analysis and parameter sampling, we show that this approach can substantially enhance constraints on the dark energy equation of state. Notably, we find that shape noise currently limits this method's effectiveness making significant improvement possible in future designs. A detailed analysis of our null test in the context of the Euclid mission is presented in a companion paper Touzeau et al. (2025).
title Novel geometrical test of cosmological expansion from photometric data
topic Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2502.02243