Do supernovae indicate an accelerating universe?

Abstract In the late 1990’s, observations of two directionally-skewed samples of, in total, 93 Type Ia supernovae were analysed framework Friedmann–Lemaître–Robertson–Walker (FLRW) cosmology. Assuming these to be ‘standard(isable) candles’ it was inferred that Hubble expansion rate is accelerating as if driven by a positive Cosmological Constant $$\varLambda $$ Λ Einstein’s theory gravity. This still only direct evidence for ‘dark energy’ dominant component today’s standard CDM cosmological model. Other data such baryon acoustic oscillations (BAO) large-scale distribution galaxies, temperature fluctuations cosmic microwave background (CMB), measurement stellar ages, growth structure, etc are all ‘concordant’ with this model but do not provide independent accelerated expansion. The recent discussions about whether acceleration real rests on analysis larger sample 740 SNe which shows quite candles, and more importantly highlights ‘corrections’ applied analyse FLRW framework. latter holds reference frame CMB isotropic, whereas carried out our heliocentric has large dipole anisotropy. assumed kinematic origin i.e. due non-Hubble motion local inhomogeneity matter grown under gravity from primordial density perturbations traced fluctuations. predicts how peculiar velocity should fall off averaging scale raised universe becomes sensibly homogeneous. However ‘bulk flow’ inconsistent expectation convergence seen. Moreover, interpretation implies corresponding sky high redshift quasars, rejected at $$4.9\sigma 4.9 σ . Hence corrections employed supernova cosmology discontinuous within data. fact anisotropic $$3.9\sigma 3.9 aligned bulk flow. Thus dark energy could an artefact analysing assuming we idealised observers universe, when inhomogeneous distances enough impact analyses.