Physics of Reality – 4: Black Hole
Complementarity
by Charles Phelan
[Charles Phelan is a fellow Blogger at the popular Advaita Vision web site. He is a financial consultant by profession but has a wide range of interests with the rare quality of clarity and in-depth understanding in the fields of physics, consciousness research, philosophy, the Western esoteric tradition, and Advaita Vedanta. He is presenting here for our Readers a series of Posts highlighting the similarities in the thought process of the modern physicists at the cutting edge and what the ancient Advaita knowledge says.
I am grateful to him for readily agreeing to my request and sparing his time for contributing to our Blog. Charles can be reached at charles@zipdebt.com -- ramesam.]
BHC is another breakthrough that
forces us to dispense with any view of a single objectively real universe, and
demonstrates yet again that “reality” is observer-dependent. Susskind
developed BHC during his decades-long battle with Stephen Hawking. The
disagreement was about a quantum loophole identified by Hawking, which became
known as the paradox of information loss in black holes, and Susskind's
theory was his proposed solution to the paradox.
Physicists call this singularity a black
hole, simply because its gravitational force is so strong that even light
cannot escape. No form of matter or energy that falls into the clutches of a
black hole can ever get free again. To get out of Earth’s gravity well and into
orbit, one must reach velocities exceeding 40,000 kilometers per hour,
something we do routinely with chemical rocketry. With a black hole, even the
speed of light is insufficient. For all practical purposes, the escape velocity
of a black hole is infinite. There are no rockets, chemical, nuclear, or
otherwise, that can possibly escape a black hole. (Sorry, Star Trek fans!)
by Charles Phelan
[Charles Phelan is a fellow Blogger at the popular Advaita Vision web site. He is a financial consultant by profession but has a wide range of interests with the rare quality of clarity and in-depth understanding in the fields of physics, consciousness research, philosophy, the Western esoteric tradition, and Advaita Vedanta. He is presenting here for our Readers a series of Posts highlighting the similarities in the thought process of the modern physicists at the cutting edge and what the ancient Advaita knowledge says.
I am grateful to him for readily agreeing to my request and sparing his time for contributing to our Blog. Charles can be reached at charles@zipdebt.com -- ramesam.]
The previous articles in this
series explored the relevance to Advaita of some of the latest research in theoretical
physics. Science is converging to a view that no description of reality can be
complete without the observer, and that so-called “objective reality” is really
more of a holographic illusion than anything truly solid or substantial.
Today's scientists are busy trying to tease apart Maya's tricks to see how this
illusion works. Leonard Susskind's theory of Black Hole Complementarity (BHC)
-- the topic of this article -- provides a good example of this driving
curiosity in action.
Dr. L. Susskind |
Before we get further into the
physics of black holes and information loss, let's briefly touch on a few
points from Advaita. The Vedas speak of in terms of vast cosmological time
scales, immense epochs (kalpas --
each but one day in the life of the creator Brahma), and the entire cycle of
creation, preservation, and dissolution, sRiShTi-sthiti-laya.
If we are to take seriously the
Advaita teachings on the accrual of puNya
and pApa (i.e., karmic merit or
demerit) to the jIva, then we can
legitimately ask: What happens to the karmic "information" during the
period of dissolution between kalpas?
Does it somehow get "recorded" and carried over to the next cycle? Or
does it get destroyed in the pralaya
phase? Asking such questions is essentially no different from asking whether
information is conserved or destroyed when it enters a black hole.
Just what is a black hole anyway? When
a star collapses at the end of its life, completely spent of fuel and no longer
able to produce fusion, it may shrink by orders of magnitude and become a white
or brown dwarf or a neutron star, depending on its original size. Given
sufficiently large mass, a star will collapse all the way to what is called a singularity,
a point where the equations of physics break down and begin producing
infinities. (Perhaps we can think of pralaya
as a form of singularity?)
Black hole |
The point at which an object
falling toward the singularity passes the point of no return is called the event
horizon. Anything passing through the event horizon is doomed to eventually
hit the singularity, where the force of gravity is so strong that a human being
gets stretched into a piece of spaghetti thousands of miles long, most
certainly not an enjoyable experience!
Dr. John Wheeler, a key 20th
century figure in theoretical physics, and mentioned previously in this series,
was also a pioneer in the study of black holes. In fact, he is the physicist
who originally coined that term. One of Wheeler's early quips was, “Black holes
have no hair.” By “no hair,” he meant they are completely smooth and
featureless, without any apparent irregularities, essentially all the same as
one another except for size. This, of course, was just Wheeler's poetic
phrasing for what the equations of General Relativity were telling him about
the structure of black holes.
Along came Stephen Hawking, who
proved that black holes are not entirely bald after all. Hawking discovered
that there was more going on with black holes than had previously been assumed,
and through a rigorous mathematical analysis he showed that they gradually evaporate
and fade away to nothing. The reason for this evaporation has to do with the
quantum entanglement of virtual particle pairs, with one part of the entangled
pair falling inside the event horizon and the other outside, i.e., “hair."
Theoretically, via this quantum mechanical process, photons are emitted as
Hawking radiation, causing the black hole to eventually evaporate and then
completely vanish.
Hawking's analysis was rigorous and
solid, and it left physicists like Leonard Susskind scratching their heads. If
Hawking was correct, then objects falling into the black hole would carry
information beyond the event horizon and into the singularity where it could
never be recovered. That, of and by itself, does not represent a problem for physics.
However, if the black hole were to fully evaporate later, then the information
would be lost forever. This is a gross violation of the most fundamental
understanding of physics, which firmly denies the possibility of any such
information loss. It would be the equivalent of taking a safe and locking some
valuables inside it, only to then watch the safe evaporate and vanish, along
with the valuables. It seemed more a magic trick than science!
Many physicists were intuitively
convinced there was something wrong with Hawking's approach, but a solution
remained elusive for decades. What it took to resolve the paradox of
information loss was a series of advances in the physics of black hole entropy
and String Theory. Combining several such breakthroughs, Leonard Susskind's
proposed solution was Black Hole Complementarity.
What BHC states is that information
falling into a black hole is reflected off a "stretched" hot horizon,
and could theoretically be recovered from the Hawking radiation, AND that information
also passes the event horizon and is eventually destroyed when it reaches the
singularity. The catch is that both observations cannot be made at the same
time, meaning that an observer outside the event horizon could confirm that
information is reflected off the event horizon, and an observer inside could
confirm information loss, but never both at the same time.
Stephen Hawking ultimately conceded
the bets he had made about information loss in black holes. It had been proven
to his satisfaction that the information going into a black hole could come
back out via the evaporative Hawking radiation itself, rather than being lost
permanently as he originally proposed. By 2008, Leonard Susskind published
his book, “The Black Hole War: My Battle with Stephen Hawking to Make the World
Safe for Quantum Mechanics.” The battle was over, but Hawking's brilliant
challenge had stimulated an entire new wave of research leading to some truly
astounding results.
(To Continue ….. Physics of Reality
– 5: will be posted on Dec 28, 2015)
Wishing All Our Readers
Season’s Greetings and
Best Wishes For a Happy And Prosperous
New Year
Best Wishes For a Happy And Prosperous
New Year
1 comment:
Fascinating. Thank you ramesam and Charles.
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