Systematic quantum corrections in bilayer cosmological holography

Develop a systematic procedure to incorporate quantum corrections into the bilayer holographic entanglement entropy framework for cosmological spacetimes without boundaries, such as de Sitter and FRW cosmologies, particularly in cases where the classical bilayer prescription involves disconnected bulk areas.

Background

The bilayer proposal identifies a holographic screen trajectory inside cosmological spacetimes—such as the pair of de Sitter horizons associated with antipodal comoving observers—and uses classical extremal-area constructions to compute entanglement. While this framework reproduces various expected features, it is only a phenomenological extension of HRT and does not straightforwardly incorporate quantum corrections.

The paper proposes a Lorentzian replica path integral generalization to cosmologies without boundaries, aiming to include first-order quantum effects. However, the authors explicitly note that a systematic way to add quantum corrections to the bilayer prescription is unclear, especially when the classical construction leads to disconnected bulk areas. This identifies a concrete gap between the classical screen-based entanglement prescription and a fully quantum-corrected formulation.