Holography on the Quantum Disk
Ahmed Almheiri, Fedor K. Popov
TL;DR
This work presents a concrete framework for holography on a noncommutative hyperbolic disk, the quantum disk, whose isometries are governed by the quantum group $SU_q(1,1)$. It develops the algebraic construction, coordinates, and a $q$-calculus to formulate wave equations, propagators, and boundary correlators, and then analyzes a putative boundary theory with $SU_q(1,1)$ symmetry, including two-point and OPE structures. The results illuminate how noncommutativity and a nontrivial coproduct imprint boundary dynamics and offer a controlled toy model that connects to the DSSYK program and its bulk dual. The study advances understanding of $q$-deformed holography, UV/IR aspects, and possible $q$-Schwarzian/CFT structures relevant for quantum gravity in noncommutative settings.
Abstract
Motivated by recent study of DSSYK and the non-commutative nature of its bulk dual, we review and analyze an example of a non-commutative spacetime known as the quantum disk proposed by L. Vaksman. The quantum disk is defined as the space whose isometries are generated by the quantum algebra $U_q(\mathfrak{su}_{1,1})$. We review how this algebra is defined and its associated group $SU_q(1,1)$ that it generates, highlighting its non-trivial coproduct that sources bulk non-commutativity. We analyze the structure of holography on the quantum disk and study the imprint of non-commutativity on the putative boundary dual.
