Ryu–Takayanagi conjecture

Shinsei Ryu and Tadashi Takayanagi published, in 2006, a conjecture within holography that posits a quantitative relationship between the entanglement entropy of a conformal field theory and the geometry of an associated anti-de Sitter spacetime. The formula characterizes "holographic screens" in the bulk; that is, it specifies which regions of the bulk geometry are "responsible to particular information in the dual CFT".

Source: Wikipedia — Ryu–Takayanagi conjecture (CC BY-SA 4.0)