Exact and Finite de Sitter QFT from CFT

Abstract: Parallel to the AdS Scale-Space construction in \cite{Yang:2026AdS}, we construct a $(d+1)$-dimensional de Sitter QFT directly from $d$-dimensional CFT data. The dS geometry is the moduli space of oriented balls, and the lifted operators are obtained by conformal-family Casimir completion. The Euclidean parent CFT gives a finite wavefunction representation, while the Minkowski parent CFT gives a double-time representation that is unitary in the parent-time polarization. This provides a CFT-based framework for reexamining puzzles of dS and double-time QFT.