Coherent Scalar Field Oscillations and the Epoch of Deceleration
Abstract
The discovery of supernova SN 1997ff at z~1.7 has confirmed the expected switch from cosmological acceleration to deceleration, as predicted by the concordance Lambda/CDM model. However, its position in the SN Ia Hubble diagram suggestes that the switch is too pronounced, which here is taken to mean that a cosmological constant is not an adequate description of the state of the vacuum. An 'oscillessence' model is invoked, with a scalar field phi governed by a simple quadratic potential, which gives a better fit to the new data point. The field is undergoing coherent oscillations, and a key feature of the proposal is that we are towards the end of the second period of acceleration; a Lambda/phi mix replaces Lambda/CDM, with Omega_Lambda~0.4 and Omega_phi~0.6.
Cite
@article{arxiv.astro-ph/0111360,
title = {Coherent Scalar Field Oscillations and the Epoch of Deceleration},
author = {J. C. Jackson},
journal= {arXiv preprint arXiv:astro-ph/0111360},
year = {2007}
}
Comments
6 pages, 4 Figures. Submitted to MNRAS