Existence of meta-observables and Hilbert space in the IFS-induced cyclic bouncing universe
Ascertain whether any gauge-invariant meta-observables exist and construct a well-defined Hilbert space for quantum gravity in the instant-folded-string–induced cyclic bouncing universe, where the dark-energy epoch is transient and no asymptotic future de Sitter boundary is present.
References
In the IFS-induced cyclic bouncing universe [Itzhaki:2025gdv], the dark energy epoch is transient, and there is no asymptotic future de Sitter boundary either; from this viewpoint, it is not clear that meta-observables exist at all [Witten2001], and it is not clear how to define, even in principle, a Hilbert space.
— Wavefunction Collapse in String Theory
(2603.24429 - Itzhaki, 25 Mar 2026) in Section 7 (Discussion)