The World as a Hologram

TL;DR

This paper explores the holographic principle suggesting our three-dimensional universe is a projection of two-dimensional data, discusses implications for high-energy physics, and considers string theory as a potential realization of this idea.

Contribution

It provides an informal implementation of 't Hooft's holographic proposal, analyzes particle growth at high energies, and links string theory models to holographic concepts.

Findings

Particles grow in size with increasing momentum, saturating causality bounds.

High-energy phenomena may be described by two-dimensional holographic data.

String theory models show similarities to holographic descriptions, suggesting a possible realization.

Abstract

According to 't Hooft the combination of quantum mechanics and gravity requires the three dimensional world to be an image of data that can be stored on a two dimensional projection much like a holographic image. The two dimensional description only requires one discrete degree of freedom per Planck area and yet it is rich enough to describe all three dimensional phenomena. After outlining 't Hooft's proposal I give a preliminary informal description of how it may be implemented. One finds a basic requirement that particles must grow in size as their momenta are increased far above the Planck scale. The consequences for high energy particle collisions are described. The phenomena of particle growth with momentum was previously discussed in the context of string theory and was related to information spreading near black hole horizons. The considerations of this paper indicate that the effect is much more rapid at all but the earliest times. In fact the rate of spreading is found to saturate the bound from causality. Finally we consider string theory as a possible realization of 't Hooft's idea. The light front lattice string model of Klebanov and Susskind is reviewed and its similarities with the holographic theory are demonstrated. The agreement between the two requires unproven but plausible assumptions about the nonperturbative behavior of string theory. Very similar ideas to those in this paper have been long held by Charles Thorn.