Simplicial Gravity and Strings

TL;DR

This paper suggests that string theory's need for extra dimensions might be due to fixed background assumptions, and that discrete simplicial gravity approaches naturally incorporate string-like degrees of freedom within a background-independent framework.

Contribution

It proposes that simplicial approaches to 3+1D quantum gravity inherently include string-like degrees of freedom, challenging the necessity of extra dimensions in string theory.

Findings

Discrete simplicial gravity in 3+1D has natural string-like degrees of freedom.

These degrees of freedom are tied to the dynamical, background-independent spacetime.

If consistent, such approaches may contain background-independent string theories.

Abstract

String theory, as a theory containing quantum gravity, is usually thought to require more dimensions of spacetime than the usual 3+1. Here I argue on physical grounds that needing extra dimensions for strings may well be an artefact of forcing a fixed flat background space. I also show that discrete simplicial approaches to gravity in 3+1 dimensions have natural string-like degrees of freedom which are inextricably tied to the dynamical space in which they evolve. In other words, if simplicial approaches to 3+1 dimensional quantum gravity do indeed give consistent theories, they may essentially contain consistent background-independent string theories.