The Three Faces of Omega_m: Testing Gravity with Low and High Redshift SN Ia Surveys

Abstract

Peculiar velocities of galaxies hosting Type Ia supernovae generate a significant systematic effect in deriving the dark energy equation of state w, at level of a few percent. Here we illustrate how the peculiar velocity effect in SN Ia data can be turned from a 'systematic' into a probe of cosmological parameters. We assume a flat Lambda-Cold Dark Matter model (w=-1) and use low and high redshift SN Ia data to derive simultaneously three distinct estimates of the matter density Omega_m which appear in the problem: from the geometry, from the dynamics and from the shape of the matter power spectrum. We find that each of the three Omega_m's agree with the canonical value Omega_m=0.25 to within 1 sigma, for reasonably assumed fluctuation amplitude and Hubble parameter. This is consistent with the standard cosmological scenario for both the geometry and the growth of structure. For fixed Omega_m = 0.25 for all three Omega_m's, we constrain gamma = 0.72 +/- 0.21 in the growth factor Omega_m(z)^gamma, so we cannot currently distinguish between standard Einstein gravity and predictions from some modified gravity models. Future surveys of thousands of SN Ia, or inclusion of peculiar velocity data, could significantly improve the above tests.

accepted for publication in MNRAS (Letters), 5 pages, 4 figures. Small changes to improve the text and the figures. Some further discussion, 1 equation and 1 reference added

References in corpus (24)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• 4D Gravity on a Brane in 5D Minkowski Space
• New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
• Cluster Abundance Constraints on Quintessence Models
• Observational Constraints on the Nature of the Dark Energy: First Cosmological Results from the ESSENCE Supernova Survey
• Improved Distances to Type Ia Supernovae with Multicolor Light Curve Shapes: MLCS2k2
• Scrutinizing Exotic Cosmological Models Using ESSENCE Supernova Data Combined with Other Cosmological Probes
• Report of the Dark Energy Task Force
• Dark Energy and Dark Gravity
• Correlated Fluctuations in Luminosity Distance and the (Surprising) Importance of Peculiar Motion in Supernova Surveys
• Fluctuations of the luminosity distance
• Separating Dark Physics from Physical Darkness: Minimalist Modified Gravity vs. Dark Energy
• Effects of Systematic Uncertainties on the Supernova Determination of Cosmological Parameters
• The Dipole Anisotropy of the 2 Micron All-Sky Redshift Survey
• A Non Parametric Model for the Cosmic Velocity Field
• Cosmological Constraints from Type Ia Supernovae Peculiar Velocity Measurements
• The Luminosity Distance in Perturbed FLRW Spacetimes
• Large-Scale Bulk Motions Complicate the Hubble Diagram
• The Peculiar Velocities of Local Type Ia Supernovae and their Impact on Cosmology
• The Velocity Field of the Local Universe from Measurements of Type Ia Supernovae
• A Comparison of Local SNIa with the IRAS PSCz Gravity Field
• Cosmological Density and Power Spectrum from Peculiar Velocities: Nonlinear Corrections and PCA
• Beyond the Thin Lens Approximation

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• Dark Energy Survey Year 1 Results: Constraints on Extended Cosmological Models from Galaxy Clustering and Weak Lensing
• Consistently Large Cosmic Flows on Scales of 100 Mpc/h: a Challenge for the Standard LCDM Cosmology
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• First-year Sloan Digital Sky Survey-II (SDSS-II) supernova results: consistency and constraints with other intermediate-redshift datasets
• Cosmic flows in the nearby Universe: new peculiar velocities from SNe and cosmological constraints
• General Relativistic N-body simulations in the weak field limit
• Banana Split: Testing the Dark Energy Consistency with Geometry and Growth
• The WiggleZ Dark Energy Survey: measuring the cosmic growth rate with the two-point galaxy correlation function
• Quantifying concordance of correlated cosmological data sets
• No evidence for bulk velocity from type Ia supernovae
• DES Y1 results: Splitting growth and geometry to test $\Lambda$CDM
• Probing gravity and growth of structure with gravitational waves and galaxies' peculiar velocity
• Parameter splitting in dark energy: is dark energy the same in the background and in the cosmic structures?
• Complementarity of Peculiar Velocity Surveys and Redshift Space Distortions for Testing Gravity
• Extending the Gravitational Growth Framework
• Turning noise into signal: learning from the scatter in the Hubble diagram
• Peculiar velocities into the next generation: cosmological parameters from the SFI++ survey
• Testing Gravity Using Type Ia Supernovae Discovered by Next-Generation Wide-Field Imaging Surveys
• Exploring the Redshift-Space Peculiar Velocity Field and its Power Spectrum
• Growth and Geometry Split in Light of the DES-Y3 Survey
• Determining accurate measurements of the growth rate from the galaxy correlation function in simulations
• Anchors no more: Using peculiar velocities to constrain $H_0$ and the primordial Universe without calibrators
• Geometry vs growth: Internal consistency of the flat ΛCDM model with KiDS-1000