Shear Correlation Functions in a Bounced Cosmology: Amplitude, Scale Dependence and Comparison with Current Surveys

This paper computes the cosmic shear correlation functions xi-plus and xi-minus for a representative source population in a standard cosmology and in a bounced cosmology whose only stated modification is a suppression of primordial power on the largest scales, with transmission rising from near zero below 0.008 h per Mpc to 0.92 well above it. At 8 arcminutes the standard model gives xi-plus of 1.777e-05 and xi-minus of 1.420e-06; the bounced variant gives xi-plus of 1.735e-05, a ratio of 0.976. At 0.5 arcminutes the ratio is 0.987, and the largest fractional change at any computed separation is 25.1 percent. The signature is therefore confined to wide separations; over the separations carrying most of the statistical weight it amounts to a few percent, below the level at which current KiDS, DES and HSC correlation functions can separate it from a small change in the overall amplitude. The result is a bound on the channel, not a detection: if a bounce is to be visible in shear correlations, it must act through a broader modification of the power spectrum than the large-scale cutoff studied here. All quantities are computed from stated assumptions, not measured.