Cosmological gravity on all scales IV: 3x2pt Fisher forecasts for pixelised phenomenological modified gravity

Abstract

Stage IV large scale structure surveys are promising probes of gravity on cosmological scales. Due to the vast model-space in the modified gravity literature, model-independent parameterisations represent useful and scalable ways to test extensions of $\Lambda$CDM. In this work we use a recently validated approach of computing the non-linear $3\times 2$pt observables in modified gravity models with a time-varying effective gravitational constant $\mu$ and a gravitational slip $\eta$ that is binned in redshift to produce Fisher forecasts for an LSST Y10-like survey. We also include in our modelling an effective nulling scheme for weak-lensing by applying the BNT transformation that localises the weak-lensing kernel enabling well-informed scale cuts. We show that the combination of improved non-linear modelling and better control of the scales that are modelled/cut yields high precision constraints on the cosmological and modified gravity parameters. We find that 4 redshift bins for $\mu$ of width corresponding to equal incremental $\Lambda$CDM growth is optimal given the state-of-the-art modelling and show how the BNT transformation can be used to mitigate the impact of small-scale systematic effects, such as baryonic feedback.

27 pages, 12 figures A few typos corrected and a couple of small changes made to the text to improve presentation of results, added missing reference. Comments welcome!

References in corpus (28)

• Dark Energy Survey Year 3 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing
• Dark energy constraints from cosmic shear power spectra: impact of intrinsic alignments on photometric redshift requirements
• A unifying description of dark energy
• Modelling baryonic feedback for survey cosmology
• The Mira-Titan Universe II: Matter Power Spectrum Emulation
• Testing Screened Modified Gravity
• Emulation of baryonic effects on the matter power spectrum and constraints from galaxy cluster data
• Hyper Suprime-Cam Year 3 Results: Cosmology from Galaxy Clustering and Weak Lensing with HSC and SDSS using the Minimal Bias Model
• Joint constraints on cosmology and the impact of baryon feedback: combining KiDS-1000 lensing with the thermal Sunyaev-Zeldovich effect from Planck and ACT
• Fast cosmological parameter estimation using neural networks
• The MillenniumTNG Project: High-precision predictions for matter clustering and halo statistics
• On the road to percent accuracy IV: ReACT -- computing the non-linear power spectrum beyond $\Lambda$CDM
• Snowmass2021 Cosmic Frontier White Paper: Ultraheavy particle dark matter
• On the road to percent accuracy V: the non-linear power spectrum beyond $\Lambda$CDM with massive neutrinos and baryonic feedback
• Fast and accurate predictions of the nonlinear matter power spectrum for general models of Dark Energy and Modified Gravity
• CosmicNet II: Emulating extended cosmologies with efficient and accurate neural networks
• Kernel-Based Emulator for the 3D Matter Power Spectrum from CLASS
• A Parameter-Masked Mock Data Challenge for Beyond-Two-Point Galaxy Clustering Statistics
• Cosmological gravity on all scales II: Model independent modified gravity $N$-body simulations
• $\text{Hi-COLA}$: Fast, approximate simulations of structure formation in Horndeski gravity
• The e-MANTIS emulator: fast predictions of the non-linear matter power spectrum in $f(R)$CDM cosmology
• Joint reconstructions of growth and expansion histories from stage-IV surveys with minimal assumptions. II. Modified gravity and massive neutrinos
• Euclid: Constraining linearly scale-independent modifications of gravity with the spectroscopic and photometric primary probes
• Revisiting Vainshtein Screening for fast N-body simulations
• On the degeneracies between baryons, massive neutrinos and f(R) gravity in Stage IV cosmic shear analyses
• Constraining $f(R)$ Gravity with a $k$-cut Cosmic Shear Analysis of the Hyper Suprime-Cam First-Year Data
• Cosmological gravity on all scales III: non-linear matter power spectrum in phenomenological modified gravity
• Post-Newtonian Gravity in Cosmology

Cited by in corpus (2)

• Principal Components for Model-Agnostic Modified Gravity with 3x2pt
• Cosmological gravity on all scales V: MCMC forecasts combining large scale structure and CMB lensing for binned phenomenological modified gravity