Probing the anisotropic local Universe and beyond with SNe Ia data

By J. Colin, Roya Mohayaee, S. Sarkar, A. Shafieloo. 2010

176 citations recorded by the source corpus.

The question of the transition to global isotropy from our anisotropic local universe is studied using the Union 2 catalogue of Type Ia supernovae (SNe Ia). We construct a ‘residual’ statistic sensitive to systematic shifts in their brightness in different directions and use this to search in different redshift slices for a preferred direction on the sky in which the SNe Ia are brighter or fainter relative to the standard Λcold dark matter (ΛCDM) cosmology. At low redshift (z 0.06) so this low-redshift bulk flow will systematically bias any reconstruction of the expansion history of the Universe. At higher redshifts z > 0.15 the agreement between the SNe Ia data and the ΛCDM model does improve, however, the sparseness and low quality of the data mean that the latter cannot be singled out as the preferred cosmological model.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/eb0d832171a3845e3c4f970dfe6c712a948916d2

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Citations in the corpus

COSMICFLOWS-2: THE DATA (2013, background): “Even with relatively small samples there have already been interesting studies of large scale flow fields (Colin et al. 2011; Dai et al. 2011; Turnbull et al. 2012).”
A Test of the Cosmological Principle with Quasars (2020, background): “Gunn (1988) had noted that this issue is closely related to the bulk flow observed in the local universe, which in fact extends out much further than is expected in the concordance ΛCDM model (e.g., Colin et al. 2011; Feindt et al. 2013).”
POWER ASYMMETRY IN WMAP AND PLANCK TEMPERATURE SKY MAPS AS MEASURED BY A LOCAL VARIANCE ESTIMATOR (2014, methodology): “Note that this procedure is strongly related to the Crossing statistic described by Shafieloo et al. (2011), Shafieloo (2012a, 2012b), which has been applied to isotropy tests with low-redshift supernovae data (Colin et al. 2011).”
Evidence for anisotropy of cosmic acceleration (2018, background): “This is reasonable as the directions of the reported bulk flows (Hudson et al. 2004; Watkins et al. 2009; Lavaux et al. 2010; Feldman et al. 2010; Colin et al. 2011; Feindt et al. 2013; Magoulas et al. 2016) are all within ∼40◦ of each other and of the CMB dipole.”
Cosmic flows in the nearby universe from Type Ia supernovae (2011, methodology): “The analysis of Colin et al. (2011) yields a bulk flow velocity of 260 ± 150 km s−1 based on SNe within 18 000 km s−1.”
Probing cosmic isotropy with a new X-ray galaxy cluster sample through the LX–T scaling relation (2020, background): “…samples that more often than not approximately match the direction of the CMB dipole (Schwarz & Weinhorst 2007; Antoniou & Perivolaropoulos 2010; Colin et al. 2011, 2017; Mariano & Perivolaropoulos 2012; Kalus et al. 2013; Appleby et al. 2015; Bengaly et al. 2015; Javanmardi et al. 2015; Migkas…”