Physics of Reality – 7: Are We
Living in a Hologram?
by Charles Phelan
Part 1
In prior segments reviewing
the work of Leonard Susskind on Black Hole Complementarity, we saw how modern physics
is pointing toward an observer-dependent reality rather than a single objective
universe. In discussing the black hole information loss paradox first identified
by Stephen Hawking in the 1970s, and the subsequent battle in physics
eventually won by Susskind, I omitted an important development that happened
along the way, and will return to it now. This is the Holographic Principle,
first proposed by Susskind in the 1990s as a consequence of his work on string
theory.
One of the weirdest results of
all the research on black hole entropy and information loss was a mathematical
calculation that determined how much "information" could be stored in
a black hole. If the event horizon – the point of no return – can be visualized
as the surface of a hollow sphere surrounding the singularity at the center,
then logically we would expect the calculation to yield a volume result since any sphere is three dimensional. However, the
bizarre outcome was that the information capacity of a black hole is limited to
the area of the surface of the event
horizon, a two-dimensional result instead of three-dimensional! It is difficult
to convey how truly strange this is!
Think of it this way. Let's
say the Earth was hollow except for a tiny diamond at the center, so the surface
of the Earth is like the event horizon, and the diamond takes the place of the
singularity at the center. Let's be quaint and take information in the form of
computer printouts filled with ones and zeroes, and then use all that paper to
fill up the hollow sphere between the crust and the center. If you were to
calculate how much paper (information) could be held inside of the hollow
sphere, the result would be based on a volume calculation for a sphere the size
of Earth, taking into account the size and thickness of the paper used for
printing the data and how much information could fit on one sheet.
Yet the result calculated by
Jacob Bekenstein – work that Susskind later built on to develop his Holographic
Principle – showed that it doesn't work that way for black holes. Again, instead
of a volume result, the equations produce an area result. It's as though no
matter how many sheets of paper with information on them are poured into the
sphere, the result for maximum information capacity will always be the surface of the sphere and not its
volume. It would be like dumping papers into the hollow sphere but never being
able to fit more than would cover the surface of the Earth. For all practical
purposes, an entire dimension is lost, and 3D becomes 2D.
Translating this astonishing
finding back to black holes, it is as though there is no “inside” of the event
horizon, that as far as anything outside the event horizon is concerned,
nothing on the other side actually exists. So from the view outside the
horizon, the information available is limited to the area of the surface of the
horizon's sphere. If this does not boggle your mind, then you're not quite grasping
the strangeness of it.
So far I haven't touched on
the issue of how information capacity could actually be calculated in the first
place, as this leads into difficult territory like Shannon entropy and the
Planck length limitation, which are beyond the scope of this article. But the
short version is that there is a smallest possible size for a single bit of
information, which allows an immense but finite
amount of information to be stored on the surface of a black hole's event
horizon. But why only an area? Why not a volume? Susskind's answer is the
Holographic Principle. Consider a simple hologram, where three-dimensional
information is inscribed in two dimensions on the surface of a plastic card or
other material. A three-dimensional projection appears at a distance from the two-dimensional
substrate and any one portion of the substrate contains information about the
whole.
Susskind's work involved
analyzing the mathematics of a special type of theoretical universe called an anti
deSitter universe. Anti de-Sitter space has a negative curvature, which results
in strange anomalies compared to a universe like our own, which is flat and
positively curved by comparison. For
example, an object thrown with sufficient velocity along a straight line in anti
de-Sitter space would eventually return to its original starting point!
As it happens, a universe made
from anti de-Sitter space is an ideal universe in which to do certain complex
calculations. Within the specific framework of the anti deSitter space,
Susskind was able to show that the total information capacity was equivalent to
the area of the cosmic boundary, and this led to his application of the term
“holographic." It is as though any apparent 3D events are really just projections from the distant 2D
information field encoded on the cosmic boundary.
It has not been proven yet
that our universe is holographic, but there has been considerable momentum in
that direction, in terms of thousands of physics papers supporting the
principle, and not just for anti deSitter space but also for regular space like
our own. At this point in the progress of modern theoretical physics, there are
still critics taking aim at potential flaws in the Holographic Principle. But
it remains a solid theory that probably deserves to be called a consensus. It
really does appear that our apparently 3D universe is just a projection from a
2D information matrix encoded on the distant cosmic boundary horizon.
How does the Holographic
Principle pertain to Advaita, or further our understanding of the nondual perspective?
Advaita teaches that the apparent creation is not actually real, that it is mithyA, a dependent reality. The Upanishads
teach that the apparent reality we observe with our senses, and even the mental
world we observe with our minds, is all just a trick by mAyA. It is all just a magic show where things appear to be one way
but are not actually as we observe. Science is beginning to tease out how some
of mAyA's tricks work. Drill down
into matter with a microscope and mathematics, and the result is nothing. Molecules contain atoms, which
contain particles like electrons or protons, which in turn contain quarks and
other members of the quantum zoo of particles, which contain – what? Tiny
one-dimensional vibrating strings that change depending on one's frame of
reference?
Drill down far enough and
there is only speculative mathematics and nothing more, nothing that is ever
unchanging or actually solid. I believe we can fairly describe all of this as mithyA, the snake in the rope, or the
ghost in the post. If it can ultimately be proven with certainty that our 3D
universe is actually just a hologram projected from a distant 2D cosmic horizon,
this would mean that the mithyA
nature of creation, known to Vedic sages for millennia, had actually been
demonstrated and accepted by modern science.
Further from the perspective
of the student of Advaita, it is fascinating to observe that modern physicists
often dance very close to discussing the role of Consciousness, but never quite
go there. Yet if reality is observer dependent, then where does the observer
come from? This is not a question addressed by physics, let alone answered by
it. Yet in result after result, modern physics seems to be converging to a view
that reality is indeed observer dependent. No observer means no universe. If we
jettison the God's eye view of reality and accept that each so-called
individual has their own reality cone, then the apparent paradoxes drop away
and all becomes much clearer. So perhaps it is only a matter of time before
some young physicist gets the bright idea to propose that Consciousness is
primary and that all else arises within it!
