Constraints on the growth rate using the observed galaxy power spectrum

Understand

The large-scale structure growth index $\gamma$ provides a consistency test of the standard cosmology and is a potential indicator of modified gravity.

• We investigate the constraints on $\gamma$ from next-generation spectroscopic surveys, using the power spectrum that is observed in redshift space, i.e., the angular power spectrum.
• The angular power spectrum avoids the need for an Alcock-Packzynski correction.
• It also naturally incorporates cosmic evolution and wide-angle effects, without any approximation.