2019/04/15 by Audrey Martin, Martin, Audrey Claire, Ian H. Redmount +1
Physics and Astronomy · Computer Science · #Cosmology and Gravitation Theories #Computational Physics and Python Applications #Dark Matter and Cosmic Phenomena
paper · pdf · doi:10.48550/arxiv.1904.07316
A Friedmann-Robertson-Walker cosmological model dominated by tachyonic -- faster-than-light -- dark matter can exhibit features similar to those of a standard dark energy/dark matter or LambdaCDM model. It can undergo expansion which decelerates to a minimum rate, passes through a "cosmic jerk," then accelerates. But some features of a tachyon-dominated model are sufficiently distinct from those of the standard model that the two possibilities might be distinguished observationally. As a demonstration of concept, the distance-redshift relation of such a model is compared here with some observations of Type Ia supernovae. Other measures of the third time derivative of the cosmic scale factor -- the true cosmic jerk -- might be found to test a tachyonic-dark-matter hypothesis.