Holography stabilizes the vacuum energy

Gravitational holography is argued to render the cosmological constant stable against divergent quantum corrections, thus providing a technically natural solution to the cosmological constant problem. Evidence for quantum stability of the cosmological constant is illustrated in a number of examples including bulk descriptions in terms of delocalized degrees of freedom, boundary screen descriptions on stretched horizons, and nonsupersymmetric conformal field theories as dual descriptions of anti-de Sitter space. In an expanding universe, holographic quantum contributions to the stress-energy tensor are argued to be at most of order the energy density of the dominant matter component.