Probing Dark Energy with Cosmological Redshift Surveys at the VLT
Large redshift surveys of galaxies play a key role in the quest for the origin of cosmic acceleration. In this context, it has recently been pointed out [L. Guzzo et al. in Nature 451, 541 (2008)] that redshift-space distortions due to galaxy peculiar motions can be used to trace the growth rate of structure f(z) back in time. Coupled to estimates of the expansion history H(z) as those provided by Type Ia supernovae, this can distinguish models with a truly extra “dark energy” component from theories in which the acceleration is explained by modifying the laws of gravity. Current measurements are not accurate enough to distinguish between these two alternatives. According to extended simulations, this will become possible with an order of magnitude increase in the sampled volume and number of redshifts at similar depth, i.e. measuring >100 000 galaxies over nearly 108 h−3 Mpc3. The VLT with VIMOS can play an important role in this endeavour, filling the gap between current surveys and projects foreseen beyond year 2015, based on new ground-based or space-born mega-MOS spectrographs.
KeywordsDark Energy Cosmic Acceleration Distortion Model Hubble Diagram Expansion History
Unable to display preview. Download preview PDF.
- 5.E.J. Copeland, M. Sami, S. Tsujikawa, preprint, hep-th/0603057
- 11.A.J.S. Hamilton, in: The Evolving Universe. ASSL, vol. 231 (Kluwer, 1998), p. 185 Google Scholar
- 15.B. Garilli et al., submitted to Astron. Astrophys. (2008) Google Scholar
- 17.M. Pierleoni et al. (2008), in preparation Google Scholar
- 20.N.P. Ross et al., Mon. Not. R. Astron. Soc. 381, 573 Google Scholar