Theories of Everything, Mapped

Quanta Magazine provides a neat, interactive guide to Theories of Everything:

TOE, an interactive guide

Simple Math Could Bridge Quantum Mechanics and General Relativity

One of the great problems of modern physics has been the failure to reconcile the theory of quantum mechanics, which deals with the behavior of fundamental particles, with Einstein’s general theory of relativity, which describes gravity and therefore the behavior of things on a larger scale.  There are some inherent contradictions in the two theories that suggest areas where our understanding is incomplete.

This article at the Scientific American website discusses a recent paper that uses "simple math" to "present a straightforward way for quantum particles to move smoothly from one kind of ‘topological space’ to a very different one."  The article notes that while this may present progress in the reconciliation of the two theories, there is no claim the the theories have been brought together in unifying a theory of quantum gravity:

The analysis does not model gravity explicitly, and so is not an attempt to formulate a theory of ‘quantum gravity’ that brings general relativity and quantum mechanics under one umbrella. Instead, the authors, including Nobel laureate Frank Wilczek of the Massachusetts Institute of Technology (MIT) in Cambridge, suggest that their work might provide a simplified framework for understanding the effects of gravity on quantum particles, as well as describing other situations in which the spaces that quantum particles move in can radically alter, such as in condensed-matter-physics experiments.

The original paper can be found here. 

The Evolution of the Physicist's Picture of Nature By Paul Dirac

1963 Article interviewing Paul Dirac

What appears to our consciousness is really a three-dimensional section of the four-dimensional picture. We must take a three-dimensional section to give us what appears to our consciousness at one time; at a later time we shall have a different three-dimensional section. The task of the physicist consists largely of relating events in one of these sections to events in another section referring to a later time. Thus the picture with four dimensional symmetry does not give us the whole situation. This becomes particularly important when one takes into account the developments that have been brought about by quantum theory. Quantum theory has taught us that we have to take the process of observation into account, and observations usually require us to bring in the three-dimensional sections of the four-dimensional picture of the universe.

The special theory of relativity, which Einstein introduced, requires us to put all the laws of physics into a form that displays four-dimensional symmetry. But when we use these laws to get results about observations, we have to bring in something additional to the four-dimensional symmetry, namely the three-dimensional sections that describe our consciousness of the universe at a certain time.

Does Every Black Hole Contain Another Universe?

Like part of a cosmic Russian doll, our universe may be nested inside a black hole that is itself part of a larger universe.

In turn, all the black holes found so far in our universe—from the microscopic to the supermassive—may be doorways into alternate realities.

The idea that black holes may be worm holes to other universes isn't new. However, in a recent paper published in the journal Physics Letters B, Indiana University physicist Nikodem Poplawski presents new mathematical models that describe how wormholes are viable alternatives to the "space-time singularities" that Albert Einstein predicted to be at the centers of black holes.

National Geographic article on Poplawski's paper

General relativity as proof of virtual reality?

Paper by Brian Whitworth who has a theory that certain aspects of relativity theory could point to our living in a virtual environment.

I found this paper interesting in that I had recently thought about the relative nature and (for instance) slowing of time for objects moving at a high rate of speed and whether these aspects of reality could be related to finite processing capability at specific points in space.

Universe as a virtual reality