3 papers
hep-th2026
Line Defects in Liouville Conformal Field Theory: Localized Cosmological Constants and Decohered Hyperbolic Geometries
Ahmed I. Abdalla, Jeevan Chandra, Yifan Wang
The study of quantum impurities has long been a central and inspiring theme in quantum many-body physics. Localized impurities are modeled by line defects in quantum field theory.…
hep-th2026
Consistent Evaluation of the No-Boundary Proposal
Ahmed I. Abdalla, Stefano Antonini, Raphael Bousso +3
We revisit the Hartle-Hawking no-boundary proposal. To extract probabilities, one must use the gravitational path integral (GPI) to compute not only the no-boundary amplitude, but…
hep-th2025
The gravitational path integral from an observer's point of view
Ahmed I. Abdalla, Stefano Antonini, Luca V. Iliesiu +1
One of the fundamental problems in quantum gravity is to describe the experience of a gravitating observer in generic spacetimes. In this paper, we develop a framework for describi…