2009/04/28 by R. Ali Vanderveld, Éanna É. Flanagan, Vanderveld, R. Ali +4
Physics and Astronomy · #Advanced Mathematical Theories and Applications #Cosmology and Gravitation Theories #Relativity and Gravitational Theory #astro-ph.CO #gr-qc
paper · pdf · doi:10.48550/arxiv.0904.4319
4 pages, no figures, revtex4
arxiv created 2009/05/07 · arxiv updated 2009/12/01
We argued in a previous paper [R. A. Vanderveld et al. 2006, arXiv:astro-ph/0602476] that negative deceleration parameters at the center of symmetry in Lemaitre-Tolman-Bondi cosmological models can only occur if the model is not smooth at the origin. Here we demonstrate explicitly the connection between non-smoothness and the failure of positivity theorems for deceleration. We also address some confusion that has arisen in the literature and respond to some recent criticisms of our arguments.