Recovery of fluctuation spectrum evolution from tomographic shear spectra

TL;DR

This paper discusses how future large-scale surveys can invert tomographic shear spectra to recover matter fluctuation spectra across redshifts, improving analysis of baryon physics and cosmological consistency.

Contribution

It demonstrates the enhanced capabilities of using 7-bin tomography with SVD techniques for more accurate fluctuation spectrum recovery from shear data.

Findings

7-bin tomography significantly improves spectrum recovery.

The method effectively propagates errors from shear to fluctuation spectra.

Potential applications include studying baryon physics and testing cosmological models.

Abstract

Forthcoming large angle surveys are planned to obtain high precision tomographic shear data. In principle, they will allow us to recover the spectra of matter density fluctuation, at various redshift, through the inversion of the expressions yielding shear from fluctuation spectra. This was discussed in previous work, where SVD techniques for matrix inversion were also shown to be the optimal tool to this aim. Here we show the significant improvements obtainable by using a 7 bin tomography, as allowed by future Euclid data, as well as the question of error propagation from shear to fluctuation spectra. We find that the technique is a promising tool, namely for the analysis of baryon physics throug high-l shear spectra and to test the consistency between expansion rate and fluctuation growth.