Interpretations of Quantum Mechanics
David Quinn
of things for me.
I read this in the Wikipedia:
--
Interpretation of Quantum Mechanics:
Quantum mechanics is a physical theory which is extremely
non-intuitive. The equations have been very successful in predicting
experimental results, but there have been a wide range of
interpretations of what those equations mean.
The need for a large range of interpretations of quantum mechanics
becomes clearer once it is mathematically demonstrated that no quantum
theory can have all of the properties one would like quantum mechanics
to have.
One inituitively would like a theory of quantum mechanics
- that is complete and not requiring any outside theory
- that is local in that the events at one point are only effected by
nearby areas
- that is deterministic which is that given one set of circumstances,
there is only one possible outcome
- that has no hidden variables
- that predicts only one universe
However, Bell's theorem appears to prevent quantum mechanics from
having all of these properties. Which property is removed results in
different interpretations of quantum mechanics.
--
This seems to suggest there are at least five different
interpretations of quantum mechanics, each one the result of
eliminating one of the five properties listed above. From what I can
gather, none of these interpretations conflict with what
is physically observed in the quantum realm, nor hinder the practical
application of the theory and its equations. As far as the math is
concerned, each interpretation is entirely neutral.
Given this, the question needs to be asked. Why has the "Copenhagan
interpretation" - which removes the 3rd property listed above - been
adopted by the physics community?
This is particularly strange, given that the removal of the 1st
property (that QM is complete and not requiring any outside theory)
would seem by far the most reasonable course of action. The fact
that physicists have chosen to reject determinism in the quantum realsm,
instead of accepting that QM is an incomplete theory, seems incomprehensible to me.
Can anyone explain this?
Andr? Michaud
If you could lay hand on a copy of a book by Franco Selleri that was
prefaced by Karl Popper, you would get a rather clean explanation
about this.
I suppose it has been translated to English, but my own copy is in
French and it's the only title I can refer you to:
"Le grand débat de la théorie quantique", by Franco Selleri.
As you may gather, the possible English title could very
well turn out to be "The Great Debate of Quantum Theory", but
who knows!
Of course there are as many opinions on this as there are authors,
as I observed as I went through quite a few of them, but Selleri's
account seems quite objective and thorough.
Although there is talk and rationalization about many interpretations,
they all boil down to either causalist or non-causalist, all
non-causalists on last analysis turning out to be plain and simple
followers of the Copenhagen school of thought.
What seems to have happened is this:
The most famous causalists (Einstein, Planck, Shrödinger, de Broglie,
et al.) believed that fundamental objective reality, that underlies
the theories that we elaborate about it, is not chaotic and obeys logical
laws that can be identified and understood, while the Copenhagen-Götingen
school of thought headed by Bohr, Eisenberg, et al. believed that there
exists no fundamental reality beyond what Quantum Mechanics can describe.
A strange turn of history seems to be responsible for the debate to
eventually die down, even before Einstein passed away, for lack of
fighters on the causalist side. Arnold Sommerfeld for example, a major
original proponent of the copenhagist view, was so viscerally opposed
to it, that he apparently taught for an extended period of his career
only the copenhagist view to group after group of students.
He was thus almost single handedly, at the origin of a complete
generation of eminent professors who had apparently only superficially
glanced at the other side of the coin and who concluded, with no reason
other than the conviction of their eminent teacher that the idea was
worthless, which translated into the causalists views and theories to
progressively cease being referred to in textbooks and thus came
to not even be minimally explained to students of the following
generations.
The non-causalist ball had started rolling and is still in full swing.
Today, physicists are unknowingly trained from the start as Copenhagists
in almost all colleges and universities without really being made
aware of the fact, and if they never personally question their own
philosophical orientation with respect to reality, naturally tend to
not even become aware that they are.
No reference book expounds anymore on the causalist viewpoint beyond
a few well known traditional showcases, like the EPR experiment for
example, which have simply become traditional causalists scapegoats
to be flogged in public, presumably because it simply is not possible
to completely disregard the major contribution of causalist scientists.
In fact, so little consideration has come to be afforded to causalists'
opinions at the international level, that despite his immense stature
as the last remaining major architect of modern physics, Louis de Broglie's,
last book seems not to even have been translated to English, although he
possibly was the keenest mind on electromagnetism of the 20th century!
From my analysis, the wide acceptance of the non-causalist option finds
its roots in the copenhagist philosophy which involves the acceptance of
irrational premises as an integral part of Quantum Mechanics, which in
turn seems to make it easier for the promoters to more readily accept
other irrational explanations to rationalize every observation that does
not logically fit accepted theories, which seems to satisfy them
sufficiently for them to consider searching for other explanations a
waste of time.
In other words, indeterminism simply is the easy way out.
Doesn't everybody love magic? :-]
Regards
André Michaud
Igor
I think the main reason that the Copenhagen interpretation has been
the preferred one is that it was the first, and most people will
stubbornly cling to the earliest version of a theory, especially when
later versions supply no additional working predictions, and so
maintain the same old physical content.
I also think that the notion of non-determinism in QM has been
overstated. So you can't predict with certainty how a system will
evolve in phase space, but we should not be too concerned about that.
The quantum realm has its own set of rules and we have to live with
them. Certainly, the wave function evolves in a deterministic way in
its own space. If you look at it that way, I think you can take a lot
of the mystery out of the theory.
Eray Ozkural exa
> Today, physicists are unknowingly trained from the start as Copenhagists
> in almost all colleges and universities without really being made
> aware of the fact, and if they never personally question their own
> philosophical orientation with respect to reality, naturally tend to
> not even become aware that they are.
I believe that is not the only reason. The "underlying" reason is that
in doctoral programs excellence in philosophy has been entirely and
without second thought divorced from the requirements to obtain a PhD
degree. Today, we educate science automatons, not scientists and for
that unphilosophical unconscious drones of today's "big and glorious
science" are sufficient.
Otherwise, a moderate physicist who had had a fleeting glance of
philosophy of mind would have known that statistical behavior might
not be primarily caused by a fundamental existence of randomness.
Fortunately, the school of Leibniz has been revived and through works
of digital physicists we are seeing a formidable alternative to the
Copenhagen interpretation!
Regards,
--
Eray
David Quinn
Thanks for your interesting comments. Do you believe that progress
in quantum theory is being hampered by the current indeterministic
mindset? Or doesn't it really matter?
The scenario that you paint seems to be reflected in cosmology as
well. The Big Bang model dominates the playing field to such an
extent that almost no research is being conducted towards developing
alternative models - such as the plasma model. It also features
irrational philosophical assumptions, such as the Universe being
created out of nothing whatsoever. And cosmologists seem to employ
various sleight-of-hand tricks to make the Big Bang model fit the
data.
I wonder if this points to an inherent deficiency in the way modern
science is conducted. Because of its increasing complexity, it is
becoming impossible to do proper objective science. There is now too
much at stake to abandon a particular line of research, as the careers
of thousands of physicists and the entire infrastructure of modern
physics is based on it. What do you think?
Andr? Michaud
>
> Thanks for your interesting comments. Do you believe that progress
> in quantum theory is being hampered by the current indeterministic
> mindset?
Absolutely.
By very definition, the Copenhagen school of thought denies that
anything could exist that would underlie Quantum Mechanics.
So, obviously, no promoter of that school of thought would even
consider doing research to further clarify something that they
don't believe exists in the first place.
> Or doesn't it really matter?
It certainly does. It slows progress down tremendously.
But Alfred Korzybski said in 1948, and I totally agree with him:
"The evolution of our human development may be retarded, but it
cannot be stopped."
> The scenario that you paint seems to be reflected in cosmology as
> well. The Big Bang model dominates the playing field to such an
> extent that almost no research is being conducted towards developing
> alternative models - such as the plasma model. It also features
> irrational philosophical assumptions, such as the Universe being
> created out of nothing whatsoever. And cosmologists seem to employ
> various sleight-of-hand tricks to make the Big Bang model fit the
> data.
My view also.
> I wonder if this points to an inherent deficiency in the way modern
> science is conducted.
It is an old trend in fact. All through history, current orthodoxies
have aggressively resisted any change that was not a direct offshoot
of currently popular premises.
Nothing new under the Sun!
All through history, self appointed "judges" of political correctness
of potential discoveries (today they name themselves "peer review
panels") have granted themselves the right to accept or refuse
publication of potentially promising papers based strictly on their
own understanding of the subjects. Understanding that can certainly be
questionned if the premises of the papers proposed were currently
unpopular.
As far back as the beginning of the 20th century, Poincaré himself
considered that they were not wrong in doing so and that they ran no
risk of smothering any serious discovery, for, as he explains: « If
you had asked academics [regarding this], they would have answered:
"We have compared the probability that an unknown scientist had found
what we have been looking for in vain for so long, to that of there
being one more fool on the Earth, the second would have appeared
greater".
Paradoxically, to explain the reluctance of academics to consider
any new idea and their recurring belief that all has already been
discovered, Poincaré wrote in the same book: "Each of us carries
within himself his own conception of the world, which he cannot so
easily dismiss." ; which, of course, is a psychological problem
that affects all humans and has nothing whatsoever to do with
science.
After having invested years of their life becomimg comfortable
with Minkowski's 4-dimensional space geometry, Special Relativity,
General Relativity, Quantum Mechanics and QED, fledgling physicists
then tend subscribe to them for good.
They are afterwards very unlikely to ever risk again losing intellectual
footing by reconsidering the whole structure, including the premises.
Unfortunately, despite the importance of the remaining problems, orthodox
theories always seem too satisfactory, and life too short, for them to
consider investing even part of their precious remaining time and
required effort in looking for potentially more appropriate alternatives
at the fundamental level.
To them, reconsidering fundamental space geometry, for example, or
trying to explore where would lead the idea that electron spin could
be due to pulsating instead of spinning, seem like useless extreme
mindbenders, or quite wrongly feel inadequate to deal with such
re-questioning, even if it could potentially cause our theories
to evolve towards solving the remaining problems.
Peer pressure to conform to the norm is also a major extinguisher
of personal initiatives.
> Because of its increasing complexity, it is becoming impossible to
> do proper objective science.
If you look and dig long enough, you will eventually come to the
conclusion that under the thick cloak of flashy mathematics that
fill so much space in so many physics papers and books, the real
stuff is not increasing in complexity, and the complexity of the
math cover often simply is an indication of the circuitous way
that the author used to get at some minute side detail of the
main subject.
I suggest choosing books that are not too mathy and go straight
to the point, with clear explanation of the equations.
> There is now too much at stake to abandon a particular line of
> research, as the careers of thousands of physicists and the entire
> infrastructure of modern physics is based on it.
There certainly must be worries about that in some quarters, but
if any really fundamental discovery was made that spelled the end
of some lines of research that became obviously misguided, I am
certain that all the scientist involved would find ample work
in projects pertaining to the new trends.
> What do you think?
I think that when the time is ripe for the next step forward to
come about, as has happened so many times in past history, no
peer review panel nor any protest nor anything else will be able
to smother or prevent the new stuff from creeping up the
metaphorical leg of the scientific community.
That's what I think.
Regards
André Michaud
Andr? Michaud
> s...@microtec.net (Andr? Michaud) wrote in message news:<562f286c.04020...@posting.google.com>...
> > Today, physicists are unknowingly trained from the start as Copenhagists
> > in almost all colleges and universities without really being made
> > aware of the fact, and if they never personally question their own
> > philosophical orientation with respect to reality, naturally tend to
> > not even become aware that they are.
>
> I believe that is not the only reason. The "underlying" reason is that
> in doctoral programs excellence in philosophy has been entirely and
> without second thought divorced from the requirements to obtain a PhD
> degree.
A net loss that is difficult to remedy.
> Today, we educate science automatons, not scientists and for
> that unphilosophical unconscious drones of today's "big and glorious
> science" are sufficient.
> Otherwise, a moderate physicist who had had a fleeting glance of
> philosophy of mind would have known that statistical behavior might
> not be primarily caused by a fundamental existence of randomness.
> Fortunately, the school of Leibniz has been revived and through works
> of digital physicists we are seeing a formidable alternative to the
> Copenhagen interpretation!
I am glad to see that reason seems to be making tentative headway again
somewhere in the community.
Regards
André Michaud
Mike Hammes
(german is my native language) from Werner Heisenberg from the year
1930 and in the argumentative way he came to his point of view which
results in the Copenhagen view seems to be the only acceptable
theoretical description of the new experimental observations. And
Werner Heisenberg is one of the Big Ones and pioneers in quantum
mechanics until today. This fact, the teaching of his legacy by the
"older" teachers and the absence of reflection by most of the students
contribute to the constancy of the Copenhagen view.
But there ARE new interpretations. And there ARE efforts to understand
the "collaps of wave-function" or the classical appearance of the
macroscopic world. Namely the "many worlds interpretation" which seems
to remove the first and the 5th property, or the concept of
"decoherence" which is just a consistent development of the existing
theory of quantum mechanics to include the environment of an
experiment as a part of the experiment. But in spite of all this
efforts the most difficult and until now not responded question is
this about the interpretation of the wave-function. Until now only the
Copenhagen-interpretation seems to offer an acceptable interpretation
for the wave-function. This is known as the statistical
interpretation. But the physicists are not very consistent in using
this interpretation. They actually do not discem between a set of
uncorrelated experiments which results in a statistical distribution
(wave-function) and a single experiment (e. g. classical trajectory of
ONE particle or the state of ONE cat in a box). And this unconsistency
ends in wondering about how the wave-function of ONE cat in a box
collaps into a classical state of that cat. If you have read well, you
see the reason: there is no wave-function for ONE cat. To get the
wave-function you have to make a set of uncorrelated cat-experiments.
And then you can calculate probabilities for each coming
cat-experiment.
Most of physicists today try to see quantum mechanics as a helpful
mathematical tool to calculate the results for technical applications
or for experiments. But they also use the manyfold of "rules of the
thumb" without trying to think about them. And these rules mostly are
coming form the Copenhagen interpretation and are teached by
none-reflecting teachers whose focal points of research are NOT
quantum mechanics.
Kind regards - Mike Hammes.
Andr? Michaud
> I have read the Handbook "Physikalische Prinzipien der Quantentheorie"
> (german is my native language) from Werner Heisenberg from the year
> 1930 and in the argumentative way he came to his point of view which
> results in the Copenhagen view seems to be the only acceptable
> theoretical description of the new experimental observations. And
> Werner Heisenberg is one of the Big Ones and pioneers in quantum
> mechanics until today. This fact, the teaching of his legacy by the
> "older" teachers and the absence of reflection by most of the students
> contribute to the constancy of the Copenhagen view.
I have read a translation of his "Der Teil und das Ganze", and what
I gather from it is that he grounds his conclusion that the
Copenhagen interpretation is the only one possible in the notion that
since a moving electron cannot be nowhere in the universe, and that
QM grants it a not nil statistical probability of being anywhere,
consequently, QM covers all possibilities, therefore, no other theory
could possibly account for more possibilities.
In my view, the fact that QM can't pinpoint the electron with 100 percent
accuracy at any point of its trajectory can't mean that the electron
will not follow at all times its least action trajectory.
In QM, this trajectory would simply relate to the path of highest
probability if the wave function could take into account the interaction
of the moving electron with other charged particles along the way.
But we know it can't. Consequently, my view is that the use of QM
should be restricted to calculate the set of orbitals in atoms, for
which it was initially conceived of.
Regards
André Michaud