Gamma Ray Bursts: Cosmic Rulers for the High-Redshift Universe?

Abstract

The desire to extend the Hubble Diagram to higher redshifts than the range of current Type Ia Supernovae observations has prompted investigation into spectral correlations in Gamma Ray Bursts, in the hope that standard candle-like properties can be identified. In this paper we discuss the potential of these new `cosmic rulers' and highlight their limitations by investigating the constraints that current data can place on an alternative Cosmological model in the form of Conformal Gravity. By fitting current Type 1a Supernovae and Gamma Ray Burst (GRB) data to the predicted luminosity distance redshift relation of both the standard Concordance Model and Conformal Gravity, we show that currently \emph{neither} model is strongly favoured at high redshift. The scatter in the current GRB data testifies to the further work required if GRBs are to cement their place as effective probes of the cosmological distance scale.

2 pages, 1 figure (black & white, colour available). To be published in "Phil. Trans. of the Royal Society" as proceedings from Discussion Meeting on Gamma Ray Bursts

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Cited by in corpus (3)

• Fitting galactic rotation curves with conformal gravity and a global quadratic potential
• Cosmological Perturbations in Conformal Gravity
• High Redshift Standard Candles: Predicted Cosmological Constraints