Is the Universe 2-Dimensional at Short Distances?

We don't have a theory of quantum gravity, but we have a number of research programs on the case. Steve Carlip has a paper (The Small Scale Structure of Spacetime) which discusses an intriguing fact: many of these otherwise disparate programs display or imply the idea that our familiar four dimensional (3 spacelike + 1 timelike) spacetime may be two dimensional (1+1) at high energies/short distances.

If 4 dimensional spacetime is an emergent phase, and the more fundamental physics is comprised of elementary, causally linked, quantum bits of some sort, you might expect this kind of dimensionality.

Here is the physics arxiv blog article on the paper.