Quintessential Maldacena-Maoz Cosmologies

TL;DR

This paper examines Maldacena-Maoz's holographic cosmology approach, showing how it circumvents known geometric theorems and demonstrating its applicability with more natural matter content, implying implications for the holography of our universe.

Contribution

It clarifies how Maldacena-Maoz cosmologies evade geometric constraints and extends their applicability to more realistic matter models.

Findings

Maldacena-Maoz approach evades Witten-Yau theorems.

Cosmologies with quintessence matter are possible.

Implications for holography of a universe with a disconnected boundary.

Abstract

Maldacena and Maoz have proposed a new approach to holographic cosmology based on Euclidean manifolds with disconnected boundaries. This approach appears, however, to be in conflict with the known geometric results [the Witten-Yau theorem and its extensions] on spaces with boundaries of non-negative scalar curvature. We show precisely how the Maldacena-Maoz approach evades these theorems. We also exhibit Maldacena-Maoz cosmologies with [cosmologically] more natural matter content, namely quintessence instead of Yang-Mills fields, thereby demonstrating that these cosmologies do not depend on a special choice of matter to split the Euclidean boundary. We conclude that if our Universe is fundamentally anti-de Sitter-like [with the current acceleration being only temporary], then this may force us to confront the holography of spaces with a connected bulk but a disconnected boundary.