• DOI:10.1103/PHYSREVD.103.023528
• Corpus ID: 222310504

DES Y1 results: Splitting growth and geometry to test ΛCDM

@article{Muir2020DESYR,
  title={DES Y1 results: Splitting growth and geometry to test 
$\Lambda$CDM},
  author={J. Muir and Eric J. Baxter and Vivian Miranda and Cyrille Doux and A. Fert{\'e} and C. Danielle Leonard and Dragan Huterer and B. Jain and Pablo Lemos and Marco Raveri and Seshadri Nadathur and A. Campos and A. Chen and Scott Dodelson and J. Elvin-Poole and S. Lee and Lucas F. Secco and Michael Troxel and Noah Weaverdyck and Joe Zuntz and Dillon J. Brout and Ami Choi and Mart{\'i}n Crocce and Tamara M. Davis and Daniel Gruen and Elisabeth Krause and Christopher E. Lidman and Niall MacCrann and Anais M{\"o}ller and Judit Prat and Ashley J. Ross and Masao Sako and Simon Samuroff and C. S{\'a}nchez and Daniel M. Scolnic and B. Zhang and Timothy M. C. Abbott and Michel Aguena and Sahar Allam and James T. Annis and Santiago {\'A}vila and David Bacon and Emmanuel Bertin and S. Bhargava and S. L. Bridle and David Brooks and David L. Burke and A. Carnero Rosell and Matias Carrasco Kind and Jorge Carretero and R. Cawthon and Matteo Costanzi and L. N. da Costa and M. E. S. Pereira and Shantanu Desai and H. Thomas Diehl and J. P. Dietrich and Peter Doel and Juan Estrada and S. Everett and August E. Evrard and I. Ferrero and Brenna L. Flaugher and Joshua A. Frieman and Juan Garc{\'i}a-Bellido and Tommaso Giannantonio and Robert A. Gruendl and Julia Gschwend and Gaston R. Guti{\'e}rrez and Samuel R. Hinton and Devon L. Hollowood and Klaus Honscheid and Ben Hoyle and David J. James and Tesla E. Jeltema and Kyler W. Kuehn and Nikolay Kuropatkin and Ofer Lahav and Marcos Lima and Marcio A. G. Maia and Felipe Menanteau and Ramon Miquel and Robert Morgan and Justin Myles and Antonella Palmese and Francisco Paz-Chinch{\'o}n and A. A. Plazas and A. K. Romer and Aaron Roodman and Eusebio S{\'a}nchez and Victor E. Scarpine and Santiago Serrano and Ignacio Sevilla-Noarbe and M. Smith and Eric Suchyta and Mollye E. C. Swanson and Gregory G. Tarl{\'e} and D. Thomas and C. To and Douglas L. Tucker and T. N. Varga and Jochen Weller and R. D. Wilkinson},
  journal={Physical Review D},
  year={2020}
}

• J. Muir, E. Baxter, +100 authors R. Wilkinson
• Published 12 October 2020
• Physics
• Physical Review D

We analyze Dark Energy Survey (DES) data to constrain a cosmological model where a subset of parameters -- focusing on $\Omega_m$ -- are split into versions associated with structure growth (e.g. $\Omega_m^{\rm grow}$) and expansion history (e.g. $\Omega_m^{\rm geo}$). Once the parameters have been specified for the $\Lambda$CDM cosmological model, which includes general relativity as a theory of gravity, it uniquely predicts the evolution of both geometry (distances) and the growth of structure over cosmic time. Any inconsistency between measurements of geometry and growth could therefore indicate a breakdown of that model. Our growth-geometry split approach therefore serves as both a (largely) model-independent test for beyond-$\Lambda$CDM physics, and as a means to characterize how DES observables provide cosmological information. We analyze the same multi-probe DES data as arXiv:1811.02375 : DES Year 1 (Y1) galaxy clustering and weak lensing, which are sensitive to both growth and geometry, as well as Y1 BAO and Y3 supernovae, which probe geometry. We additionally include external geometric information from BOSS DR12 BAO and a compressed Planck 2015 likelihood, and external growth information from BOSS DR12 RSD. We find no significant disagreement with $\Omega_m^{\rm grow}=\Omega_m^{\rm geo}$. When DES and external data are analyzed separately, degeneracies with neutrino mass and intrinsic alignments limit our ability to measure $\Omega_m^{\rm grow}$, but combining DES with external data allows us to constrain both growth and geometric quantities. We also consider a parameterization where we split both $\Omega_m$ and $w$, but find that even our most constraining data combination is unable to separately constrain $\Omega_m^{\rm grow}$ and $w^{\rm grow}$. Relative to $\Lambda$CDM, splitting growth and geometry weakens bounds on $\sigma_8$ but does not alter constraints on $h$.