Stress-testing the spatially flat Universe: nonparametric spatial curvature determination from DESI DR2
We present a nonparametric determination of spatial curvature using only late-time geometrical probes. Under a Gaussian Process smoothness prior, we jointly constrain the dimensionless expansion history and $\Omega_K$, combining three Type Ia Supernovae (SNeIa) samples with either DESI DR2 line-of-sight baryon acoustic...