Whether we actually live in a hologram is being hotly
debated, but it is now becoming clear that looking at phenomena through a holographic lens could be key to solving some of the
most perplexing problems in physics. Last month, Japanese physicists presented
in Nature News as "the clearest evidence
yet that our Universe could be just one big projection." The universe
existing as a ‘hologram’ is the theory that the three dimensions we perceive
are actually just “painted” onto the cosmological horizon - the boundary of the known universe.

In two papers on arXiv, that represent the the culmination
of many years’ work focused on hypothetical calculations of the energies of
black holes in different universes, Yoshifumi Hyakutake and colleagues from Ibaraki University in Japan
offer evidence that supports a theory that suggests that a universe as we conceive
of it could actually be a hologram of another two-dimensional space --a
holographic projection of another, flat version of you living on a
two-dimensional "surface" at the edge of this universe. This radical
model of the universe helps explain some inconsistencies between general
relativity (Einstein’s theory) and quantum physics. At certain extremes (such
as in the center of a black hole) Einstein's theory break down and the laws of
quantum physics take over.

The standard method of reconciling these two models has come
from the 1997 work of theoretical physicist Juan Maldacena, at the Institute for Advanced
Studies in Princeton, who proposed a radical model of the Universe in which
gravity arises from infinitesimally thin, vibrating strings which exist in nine
dimensions of space plus one of time, and would be a hologram --a simpler,
flatter cosmos where there is no gravity.

Maldacena's theory provided physicists with a mathematical
Rosetta stone, a 'duality', that allowed them solve problems in one model that
seemed unsolvable in the other, but has yet to receive a rigorous proof. A
theory that Columbia University mathematican PeterWoit describes as "not even wrong."

In one paper2 described in Nature, Hyakutake computes the internal energy of
a black hole, the position of its event horizon (the boundary between the black
hole and the rest of the Universe), its entropy and other properties based on
the predictions of string theory as well as the effects of so-called virtual
particles that continuously pop into and out of existence. Paper 3, calculates
the internal energy of the corresponding lower-dimensional cosmos with no
gravity. The two computer calculations match.

Maldacena embraced the new research as “an interesting way
to test many ideas in quantum gravity and string theory.” “The whole sequence
of papers is very nice because it tests the dual [nature of the universes] in
regimes where there are no analytic tests," he added.

”Leonard Susskind, a theoretical
physicist at Stanford University who was among the first theoreticians to
explore the idea of holographic universes and was one of the founders of string
theory, added that the work by the Japanese team “numerically confirmed,
perhaps for the first time, something we were fairly sure had to be true, but was
still a conjecture.”

Maldacena concluded that "the numerical proof that
these two seemingly disparate worlds are actually identical gives hope that the
gravitational properties of our Universe can one day be explained by a simpler
cosmos purely in terms of quantum theory."

Via Nature
News and Nature doi:10.1038/nature.2013.14328

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