Quantification of high dimensional non-Gaussianities and its implication to Fisher analysis in cosmology

Understand

It is well known that the power spectrum is not able to fully characterize the statistical properties of non-Gaussian density fields.

• Recently, many different statistics have been proposed to extract information from non-Gaussian cosmological fields that perform better than the power spectrum.
• The Fisher matrix formalism is commonly used to quantify the accuracy with which a given statistic can constrain the value of the cosmological parameters.
• However, these calculations typically rely on the assumption that the likelihood of the considered statistic follows a multivariate Gaussian distribution.