  Due to their highly luminous nature, gamma-ray bursts (GRBs) are useful tools
in studying the early Universe (up to z = 10). We consider whether the
available subset of Swift high redshift GRBs are unusual when compared to
analogous simulations of a bright low redshift sample. By simulating data from
the Burst Alert Telescope (BAT; Barthelmy et al. 2005) the light curves of
these bright bursts are obtained over an extensive range of redshifts,
revealing complicated evolution in properties of the prompt emission such as
T90.

High Energy Astrophysical Phenomena