> space—and perhaps even time—is not fundamental. Instead #space and #time may be emergent: they could arise from the structure and behavior of more basic components of nature.
> best theory of #gravity is general #relativity , Albert Einstein’s famous conception of how matter warps space and time
> best #theory_o_everything else is #quantum #physics
> But the two theories don’t play nicely
> Nature knows how to apply gravity in quantum contexts—it happened in the first moments of the #big_bang, and it still happens in the hearts of #black_holes —but we humans are still struggling to understand how the trick is done.
> quantum physics treats space and time as immutable, general relativity warps them
> If #spacetime is #emergent, then figuring out where it comes from—and how it could arise from anything else—may just be the missing key that finally unlocks the door to a theory of everything.
> uncovered a duality between a kind of well-understood quantum theory known as a conformal field theory (CFT) and a special kind of spacetime from general relativity known as anti–de Sitter space (AdS).
> The two seem to be wildly different theories—the CFT has no gravity in it whatsoever, and the AdS space has all of Einstein’s theory of gravity thrown in. Yet the same mathematics can describe both worlds.
> Based on some of the peculiar characteristics of black holes, ’t Hooft and Susskind suspected that the properties of a region of space might be fully “encoded” by its boundary.
> in the AdS/CFT correspondence, the four-dimensional CFT encodes everything about the five-dimensional AdS space it is associated with. In this system, the entire region of spacetime is built out of interactions between the components of the quantum system in the conformal field theory.
> If this space is emergent, what is it emerging from? The answer is a special and strangely quantum kind of interaction in the CFT: #entanglement, a long-distance #connection between objects, instantaneously correlating their behavior
> entanglement is what produces distances in the AdS space in the first place. Any two nearby regions of space on the AdS side of the duality correspond to two highly #entangled quantum components of the CFT.
> this relation might apply to our universe as well.
> “What is it that holds the space together and keeps it from falling apart into separate subregions? The answer is the entanglement
> space itself emerges out of a fundamentally quantum phenomenon
... and this is only the skeleton of 1 of 2 new theories that intend to explain space (and probably time) as emergent. If you're on these matters you must read the article in full.
What Is Spacetime Really Made Of?
https://www.scientificamerican.com/article/what-is-spacetime-really-made-of/