Simulating the Effect of Non-Linear Mode-Coupling in Cosmological Parameter Estimation

Understand

Fisher Information Matrix methods are commonly used in cosmology to estimate the accuracy that cosmological parameters can be measured with a given experiment, and to optimise the design of experiments.

• However, the standard approach usually assumes both data and parameter estimates are Gaussian-distributed.
• Further, for survey forecasts and optimisation it is usually assumed the power-spectra covariance matrix is diagonal in Fourier-space.
• But in the low-redshift Universe, non-linear mode-coupling will tend to correlate small-scale power, moving information from lower to higher-order moments of the field.