A Positive Cosmological Constant in String Theory Through Ads/CFT Wormholes

TL;DR

This paper proposes a novel approach to reconcile a positive cosmological constant with string theory by embedding wormholes in string backgrounds, using AdS/CFT correspondence and brane-world scenarios.

Contribution

It introduces a framework where wormholes in string backgrounds support positive cosmological constants within string theory, linking brane-worlds and AdS/CFT correspondence.

Findings

Brane-worlds with positive cosmological constants lead to bulk singularities resolved by AdS/CFT wormholes.

IR stability of matter in wormholes necessitates the presence of a brane-world.

UV stability conditions prevent negative cosmological constants on the brane-world.

Abstract

There are two important examples of physical systems which violate the strong energy condition : Universes (like, it would seem, our own) with a positive cosmological constant, and wormholes. We suggest that a positive cosmological constant can be reconciled with string theory by considering wormholes in string backgrounds. This is argued in two directions : first, we show that brane-worlds with positive cosmological constants give rise to bulk singularities which are best resolved by embedding the brane-world in an AdS/CFT wormhole; and second, for the simplest kind of wormhole in an asymptotically AdS space, we show that the IR stability of the matter needed to keep the wormhole open requires the presence of a brane-world. UV stability conditions then forbid a negative cosmological constant on the brane-world.