John O. Campbell
Wojciech Zurek’s highly productive career unravelling quantum
mysteries spans thirty-five years and places him among the greatest living quantum theorists. As a result he
is the top pick of a Scientific American blog for the Nobel Prize in physics (1). One of his most
noted accomplishments is the discovery of the mechanisms of quantum
interactions or of quantum decoherence.
He describes quantum interactions as the copying of quantum
information from a quantum system into its environment. The copied information
is highly variable with only an extremely small subset able to survive and reproduce
in its environment - and that surviving information forms classical reality.
Those with a broad scientific background may spot an analogy
between Zurek’s description of quantum interactions and the process of natural
selection. This analogy has not escaped Zurek and he named his overall theory
of quantum interactions: Quantum Darwinism.
This is perhaps a shocking choice for the naming of a
fundamental physical theory. Traditionally physicists have expressed a good
deal of disdain for biologists, often considering them mere ‘stamp collectors’
or scientific wannabes. Biologists responded by donning clipboards and lab
coats in an attempt to ape the harder sciences. It is therefore surprising that
a leading physicist would borrow the central biological paradigm in naming a
fundamental theory.
After ten years of development by Zurek and a small group of
collaborators, it seems obvious that this theory is both correct and an
intellectual milestone of scientific understanding. Also, perhaps due to its
biological condescension, it has been largely ignored in the scientific
literature as well as in the press. Due to its biological taint many physicists
seem unable or unwilling to consider it as a serious proposal.
Given this situation, Zurek’s insights into biological
theory and his courage in naming this physical theory are remarkable. How did
this career physicist come to have such respect for biology? Zurek has
addressed this specific question and the short answer is that he inherited much
of it from his mentor, the great physicist John Archibald Wheeler (2).
This was symptomatic of the role theme of evolution played in John’s thinking about physics (see, e.g., Wheeler’s ideas on the evolutionary origin of physical laws). While I was always fond of looking at the ‘natural world’ in Darwinian terms, this tendency was very much encouraged by John’s influence.It seems quite natural to look at the emergence of the classical as a consequence of a quantum analogue of natural selection. Last not least (and on a lighter note) while my wife Anna and I were visiting John on his ‘High Island’ summer estate in Maine, we were put up in a cottage in which – I was told – James Watson wrote “The Double Helix”...
Wheeler was lead author of the most electrifying scientific
textbook I have ever experienced: Gravitation. Although this treatise on
general relativity was published only eight years after the Big Bang model had
been experimentally confirmed, the historical nature of the universe permeates
the book (3):
Since the discovery of the cosmic microwave radiation in 1965, extensive theoretical research has produced a fairly detailed picture of how the universe probably evolved into its present state.
The adoption of Big Bang cosmology marked a revolution in
physical thinking. The previous consensus theory was the ‘Steady State’ model
where the universe had remained largely the same since the beginning. The
notion that the universe had a historical context and had perhaps even ‘evolved’
opened up a new realm of understanding and explanation.
Providing the universe with an historical context allowed us
to understand it in the traditional manner; ‘things are the way they are
because of how they got that way’. This is the common-sense way we explain most
things from who we are as mature individuals to explanations for the current
state of our car. However it was new to physics which had mouldered in the
Newtonian paradigm of given initial conditions and timeless laws, both of which
are inexplicable within the theory itself.
Zurek also notes the curious fact that Wheeler had only two
pictures on his office walls and both were portraits: one of Lincoln and one of
Darwin (2). These two great men
may seem a disparate combination. However,
I would like to speculate upon a possible commonality that Wheeler may have perceived
and appreciated: the importance each ascribed to our historic heritage, our formation by the past, which
they considered essential aspects of life.
Lincoln felt compelled to order the greatest spilling of blood in American
history due to his commitment to the historic perspective. At the
dedication of the Gettysburg National Cemetery, commemorating fifty thousand casualties
in a single battle, he made a short speech of only 273 words, one that left an
indelible mark upon the world. He started by recounting a historical event:
Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty, and dedicated to the proposition that all men are created equal.
The point of Lincoln’s short address was that the preservation
of the wondrous aspirations expressed in the American Declaration of
Independence were so important to each American that they justified the deaths
of so many. He was girding the nation to make even greater sacrifices so that:
this nation, under God, shall have a new birth of freedom—and that government of the people, by the people, for the people, shall not perish from the earth.
Here was an assertion that the historical course which
America had taken towards democracy was of even greater value than the lives of
hundreds of thousands of its citizens. Humanity's road from autocracy towards democracy has been a
long historical process with the majority of its more modern milestones taking place
in America and Britain (4). Lincoln’s
Gettysburg Address was one such milestone and another was the decision of
Britain to defy the Nazi menace in WWII, alone and against seemingly
overwhelming odds.
Following the fall of France in 1940, many in the British establishment
believed the only reasonable course was to make a deal with Germany, to negotiate
a conditional surrender. Winston Churchill, himself a historian, saw clearly
that a deal with Germany would mean surrendering the most important aspects of
being British, the most essential parts of British life that had slowly developed over a thousand years. Perhaps surprisingly the
opposition to Churchill was strongest among the political elite in the government
cabinet. The House of Commons, as well as the average Briton, wildly endorsed
his resolve to ‘fight them on the beaches’ and enthusiastically rallied to the
cause.
Churchill understood the war in a historic context, he
understood that a new ‘dark age’ was at risk:
But if we fail, then the whole world, including the United States, including all that we have known and cared for, will sink into the abyss of a new Dark Age made more sinister, and perhaps more protracted, by the lights of perverted science.
Let us therefore brace ourselves to our duties, and so bear ourselves that if the British Empire and its Commonwealth last for a thousand years, men will still say, 'This was their finest hour.'
Charles Darwin was another Briton who introduced a
revolutionary historical perspective. His focus was biological history rather
than cultural history. Before Darwin biological thought was largely constrained
by Christian scripture. The consensus interpretation of Biblical teaching was
that God had created all species in 4004 BC[i]
and those species had remained static since.
Some, such as Robert Chambers and Darwin’s own grandfather
Erasmus Darwin, had suggested that species may have evolved but no one prior to
Charles Darwin was able to describe a convincing mechanism for this evolution.
Darwin’s theory of natural selection has extended our historical context from
culture to biology, it extended our family relations from mankind to all
organisms, and it extended our historical context to 3.5 billion years.
I believe Wheeler may have appreciated this commonality
between Lincoln and Darwin. He was certainly enthusiastic about pushing the
historical limits of the universe even further to 13.5 billion years with the Big Bang
theory. However neither Wheeler nor any other physicists was able to suggest a
mechanism by which the universe had evolved.
He was among the first to understand that information is,
perhaps the most fundamental aspect of the physical world. Indeed all physics
depends upon the transfer of information in the form of one of the four
fundamental physical forces. Each of these forces are understood in terms of
quantum interactions and now Wojciech Zurek has shown that these quantum
interactions take place through a Darwinian process.
The implications are breathtaking because the history of the
universe is the history of those interactions which have taken place. With
Zurek’s theory we may view the physical evolution of the universe essentially as probing
for and discovering those states capable of survival and reproductive success
within their environments.
All physical forms are described by their quantum
interactions and these include even biological organisms and cultural
structures. While these process may be guided by higher order principles such
as natural selection, at bottom they also conform to the principles of Quantum
Darwinism. In this view we are composed of and have evolved from a nested
hierarchy of related structures: cultural, behavioural, biological and physical.
Our own direct historical lineage extends to the beginnings of the universe and
we are the recipients of a wondrous historical heritage.
Many paleontologists and anthropologists describe our planet’s
current historic epoch in terms of a sixth mass extinction. A mass extinction
is considered to have occurred in earth’s history when more than 50% of its
species become extinct during a short period of time. Five such events have
been identified in our previous history. All five cases involved natural agents,
such as a meteorite collision or extensive volcanism. This sixth case is
different, the agent involved is us. In some sense we cannot be blamed, many of
us do not recognize our close familial relationship to all the other organisms
on the planet.
However the fact remains that we are inadvertently but actively exterminating
our cousins in the family of life. Hopefully some Lincoln or Churchill will
emerge to remind us of our duty to safeguard our great historic and familial heritage.
Hopefully we will rally to them and ensure that no more of our extended family or
our historic heritage shall perish from the face of the earth.
Bibliography
1. Ouellette, Jennifer.
Nobel Crystal Ball: Predictions for the 2014 Prize in Physics. Scientific
American. [Online] October 3, 2014. [Cited: December 12, 2014.] http://blogs.scientificamerican.com/cocktail-party-physics/2014/10/03/nobel-crystal-ball-predictions-for-2014-prize-in-physics/.
2. Zurek, Wojciech H. Quantum Darwinism and
envariance. [book auth.] P. C. W. Davies, and C. H. Harper, eds. J. D.
Barrow. Science and Ultimate Reality: From the Quantum to the Cosmos. s.l. :
Cambridge University Press, 2004.
3. Misner, Charles, Thorne, Kip and Wheeler, John
Archibald. Gravitation. s.l. : W.H. Freeman and Company,
1973.
4. Wikipedia. Democracy. Wikipedia. [Online]
http://en.wikipedia.org/wiki/Democracy.
[i]
After careful study of
Biblical chronology, Archbishop Ussher set the date of creation at 4004 B.C.
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