Can a void mimic the Lambda in Lambda CDM?
Number of Authors: 3
2015 (English)In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 8, 037Article in journal (Refereed) Published
We investigate Lematre-Tolman-Bondi (LTB) models, whose early time evolution and bang time are homogeneous and the distance-redshift relation and local Hubble parameter are inherited from the Lambda CDM model. We show that the obtained LTB models and the Lambda CDM model predict different relative local expansion rates and that the Hubble functions of the models diverge increasingly with redshift. The LTB models show tension between low redshift baryon acoustic oscillation and supernova observations and including Lyman-alpha forest or cosmic microwave background observations only accentuates the better fit of the Lambda CDM model compared to the LTB model. The result indicates that additional degrees of freedom are needed to explain the observations, for example by renouncing spherical symmetry, homogeneous bang time, negligible effects of pressure, or the early time homogeneity assumption.
Place, publisher, year, edition, pages
2015. no 8, 037
dark energy theory, supernova type Ia, standard candles, baryon acoustic oscillations, CMBR theory
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-123865DOI: 10.1088/1475-7516/2015/08/037ISI: 000365046600037OAI: oai:DiVA.org:su-123865DiVA: diva2:878355