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What the Bleep Do We Know (реферат)

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What the Bleep Do We Know!?

“The
important thing is not to stop questioning. Curiosity

has its own
reason for existing. One cannot help but be in

awe when one
contemplates the mysteries of eternity, of life,

of the
marvelous structure of reality. Itis enough if one tries

merely to
comprehend a little of this mystery every day.

Never lose a
holy curiosity.” – Albert Einstein

At the core of this report are provocative questions about the way we
participate in an unfolding, dynamic reality. What the Bleep Do We
Know!? proposes that there is no solid, static universe, and that
reality is mutable – affected by our very perception of it. At the same
time, the report acknowledges that reality is not entirely relative or
simply created out of thin air. Mothers do give birth to real babies.
Some things are more solid and reliable than others.

In fact, according to quantum physics, things are not even “things”,
they are more like possibilities. According to physicist Amit Goswami,
“Even the material world around us – the chairs, the tables, the rooms,
the carpet, camera included – all of these are nothing but possible
movements of consciousness.” What are we to make of this? “Those who are
not shocked when they first come across quantum theory cannot possibly
have understood it,” notes quantum physics pioneer Niels Bohr. Before we
can consider the implications of quantum mechanics, let’s make sure we
understand the theory.

What is Quantum Mechanics?

What is Quantum Mechanics? Quantum mechanics, the latest development in
the scientific quest to understand the nature of physical reality, is a
precise mathematical description of the behavior of fundamental
particles. It has remained the preeminent scientific description of
physical reality for 70 years. So far all of its experimental
predictions have been confirmed to astounding degrees of accuracy. To
appreciate why quantum mechanics continues to astound and confound
scientists, it is necessary to understand a little about the historical
development of physical theories.

Keeping in mind that this brief sketch oversimplifies a very long, rich
history, we may consider that physics as a science began when Isaac
Newton and others discovered that mathematics could accurately describe
the observed world. Today the Newtonian view of physics is referred to
as classical physics; in essence, classical physics is a mathematical
formalism of common sense. It makes four basic assumptions about the
fabric of reality that correspond more or less to how the world appears
to our senses. These assumptions are reality, locality, causality, and
continuity.

Quantum reality

Reality refers to the assumption that the physical world is objectively
real. That is, the world exists independently of whether anyone is
observing it, and it takes as selfevident that space and time exist in a
fixed, absolute way. Locality refers to the idea that the only way that
objects can be influenced is through direct contact. In other words,
unmediated action at a distance is prohibited. Causality assumes that
the arrow of time points only in one direction, thus fixing
cause-and-effect sequences to occur only in that order. Continuity
assumes that there are no discontinuous jumps in nature, that space and
time are smooth. Classical physics developed rapidly with these
assumptions, and classical ways of regarding the world are still
sufficient to explain large segments of the observable world, including
chemistry, biology, and the neurosciences. Classical physics got us to
the moon and back. It works for most things at the human scale. It is
common sense.

But it does not describe the behavior of all observable outcomes,
especially the way that light – and, in general, electromagnetism –
works. Depending on how you measure it, light can display the properties
of particles or waves. Particles are like billiard balls. They are
separate objects with specific locations in space, and they are hard in
the sense that if hurled at each other with great force, they tend to
annihilate each other accompanied by dazzling displays of energy. In
contrast, waves are like undulations in water. They are not localized
but spread out, and they are soft in that they can interact without
destroying each other. The wave-like characteristic also gives rise to
the idea of quantum superposition, which means the object is in a
mixture of all possible states. This indeterminate, mixed condition is
radically different than the objects we are familiar with. Everyday
objects exist only in definite states. Mixed states can include many
objects, all coexisting, or entangled, together.

How is it possible for the fabric of reality to be both waves and
particles at the same time? In the first few decades of the twentieth
century, a new theory, Quantum Mechanics, was developed to account for
the wave-particle nature of light and matter. This theory was not just
applicable to describing elementary particles in exotic conditions, but
provided a better way of describing the nature of physical reality
itself.

Einstein’s Theory of Relativity also altered the Newtonian view of the
fabric of reality, by showing how basic concepts like mass, energy,
space, and time are related. Relativity is not just applicable to
cosmological domains or to objects at close to light-speeds, but refers
to the basic structure of the fabric of reality. In sum, modern physics
tells us that the world of common sense reveals only a special, limited
portion of a much larger and stranger fabric of reality.

Electrons can behave as both particles and waves. As waves, electrons
have no precise location but exist as “probability fields.” As
particles, the probability field collapses into a solid object in a
particular place and time. Unmeasured or unobserved electrons behave in
a different manner from measured ones. When they are not measured,
electrons are waves. When they are observed, they become particles. The
world is ultimately constructed out of elementary particles that behave
in this curious way.

In classical physics, all of an object’s attributes are in principle
accessible to measurement. Not so in quantum physics. You can measure a
single electron’s properties accurately, but not without producing
imprecision in some other quantum attribute.

Quantum properties always come in “conjugate” pairs. When two properties
have this special relationship, it is impossible to know about both of
them at the same time with complete precision. Heisenberg’s Uncertainty
(also know as the Indeterminacy) Principle says that if you measure a
particle’s position accurately, you must sacrifice an accurate knowledge
of its momentum, and vice versa. A relationship of the Heisenberg kind
holds for all dynamic properties of elementary particles and it
guarantees that any experiment (involving the microscopic world) will
contain some unknowns.

What does the phrase “we know” mean? It means that theoretical
predictions were made, based on mathematical models, and then repeatedly
demonstrated in experiments. If the universe behaves according to the
theories, then we are justified in believing that common sense is indeed
a special, limited perspective of a much grander universe.

The portrait of reality painted by relativity and quantum mechanics is
so far from common sense that it raises problems of interpretation. The
mathematics of the theories are precise, and the predictions work
fantastically well. But translating mathematics into human terms,
especially for quantum mechanics, has remained exceedingly difficult.

The perplexing implications of quantum mechanics were greeted with shock
and awe by the developing scientists. Many physicists today believe that
a proper explanation of reality in light of quantum mechanics and
reliability requires radical revisions of one or more common-sense
assumptions: reality, locality, causality or continuity.

Given the continuing confusions in interpreting quantum mechanics, some
physicists refuse to accept the idea that reality can possibly be so
perplexing, convoluted, or improbable – compared to common sense, that
is. And so they continue to believe, as did Einstein, that quantum
mechanics must be incomplete and that once “fixed” it will be found that
the classical assumptions are correct after all, and then all the
quantum weirdness will go away. Outside of quantum physics, there are a
few scientists and the occasional philosopher who focus on such things,
but most of us do not spend much time thinking about quantum mechanics
at all. If we do, we assume it has no relevance to our particular
interests. This is understandable and in most cases perfectly fine for
practical purposes. But when it comes to understanding the nature of
reality, it is useful to keep in mind that quantum mechanics describes
the fundamental building blocks of nature, and the classical world is
composed of those blocks too, whether we observe them or not. The
competing interpretations of quantum mechanics differ principally on
which of the common-sense assumptions one is comfortable in giving up.

Interpretations

Copenhagen Interpretation – This is the orthodox interpretation of
quantum mechanics, promoted by Danish physicist Niels Bohr (thus the
reference to Copenhagen, where Bohr’s institute is located). In an
overly simplified form, it asserts that there is no ultimately knowable
reality. In a sense, this interpretation may be thought of as a “don’t
ask–don’t tell” approach that allows quantum mechanics to be used
without having to care about what it means. According to Bohr, it means
nothing, at least not in ordinary human terms.

Wholeness – Einstein’s protege David Bohm maintained that quantum
mechanics reveals that reality is an undivided whole in which everything
is connected in a deep way, transcending the ordinary limits of space
and time.

Many Worlds – Physicist Hugh Everett proposed that when a quantum
measurement is performed, every possible outcome will actualize. But in
the process of actualizing, the universe will split into as many
versions of itself as needed to accommodate all possible measurement
results. Then each of the resulting universes is actually a separate
universe.

Quantum Logic – This interpretation says that perhaps quantum mechanics
is puzzling because our common sense assumptions about logic break down
in the quantum realm. Mathematician John von Neumann developed a “wave
logic” that could account for some of the puzzles of quantum theory
without completely abandoning classical concepts. Concepts in quantum
logic have been vigorously pursued by philosophers.

NeoRealism – This was the position led by Einstein, who refused to
accept any interpretation, including the Copenhagen Interpretation,
asserting that common sense reality does not exist. The neorealists
propose that reality consists of objects familiar to classical physics,
and thus the paradoxes of quantum mechanics reveal the presence of flaws
in the theory. This view is also known as the “hidden variable”
interpretation of quantum mechanics, which assumes that once we discover
all the missing factors the paradoxes will go away.

Consciousness Creates Reality – This interpretation pushes to the
extreme the idea that the act of measurement, or possibly even human
consciousness, is associated with the formation of reality. This
provides the act of observation an especially privileged role of
collapsing the possible into the actual. Many mainstream physicists
regard this interpretation as little more than wishful New Age thinking,
but not all. A few physicists have embraced this view and have developed
descriptive variations of quantum theory that do accommodate such ideas.

It should be emphasized that at present no one fully understands quantum
mechanics. And thus there is no clear authority on which interpretation
is more accurate.

Additional Resources

BOOKS

Davies, P. C. W. The Ghost in the Atom: A Discussion of the Mysteries of
Quantum

Physics. Cambridge University Press, 1986.

Feynman, Richard. QED: The Strange Theory of Light and Matter. Princeton
University

Press, 1985.

Greene, Brian. The Elegant Universe: Superstrings, Hidden Dimensions,
and the Quest

for the Ultimate Theory. Vintage, 2000.

Hawking, Stephen. A Brief History of Time: The Updated and Expanded
Tenth

Anniversary Edition. Bantam, 1998.

Heisenberg, Werner. Physics and Philosophy: The Revolution in Modern
Science. Harper

and Row, 1958.

Heisenberg, Werner. Physics and Beyond: Encounters and Conversations.
Harper and

Row, 1971.

Herbert, Nick. Quantum Reality: Beyond the New Physics. Anchor Books,
1987.

McFarlane, Thomas. The Illusion of Materialism: How Quantum Physics
Contradicts the

Belief in an Objective World Existing Independent of Observation. Center
Voice: The

Newsletter of the Center for Sacred Sciences, Summer-Fall 1999.

Zukav, Gary. The Dancing Wu Li Masters. Bantam Books, 1990.

INTERNET

Heisenberg and Uncertainty: A Web Exhibit American Institute of Physics

www.aip.org/history/heisenberg/

Measurement in Quantum Mechanics: Frequently Asked Questions edited by
Paul Budnik

www.mtnmath.com/faq/meas-qm.html

The Particle Adventure: An interactive tour of fundamental particles and
forces

Lawrence Berkeley National Laboratory www.particleadventure.org

Discussions with Einstein on Epistemological Problems in Atomic Physics,
Niels Bohr (1949)

www.marxists.org/reference/subject/philosophy/works/dk/bohr.htm

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