The Personal Website of Mark W. Dawson
Containing His Articles, Observations, Thoughts, Meanderings,
and some would say Wisdom (and some would say not).
The Copenhagen Interpretation
"Reality is the business of physics."  Albert Einstein
There are several important issues regarding the current science
of Quantum Theory. The most basic is what is the reality
underlying the Quantum world. The Copenhagen
Interpretation is a collection of views about the meaning of
quantum mechanics principally attributed to Niels Bohr and Werner
Heisenberg. It is one of the oldest of numerous proposed
interpretations of quantum mechanics, as the features of it date
to the development of quantum mechanics during 1925â€“1927, and it
remains one of the most commonly taught.
There is no definitive historical statement of what the
Copenhagen interpretation is. There are some fundamental
agreements and disagreements between the views of Bohr and
Heisenberg. For example, Heisenberg emphasized a sharp "cut"
between the observer (or the instrument) and the system being
observed, while Bohr offered an interpretation that is independent
of a subjective observer or measurement or collapse, which relies
on an "irreversible" or effectively irreversible process, which
could take place within the quantum system.
Features common to Copenhagentype interpretations include the
idea that quantum mechanics is intrinsically indeterministic, with
probabilities calculated using the Born rule, and the principle of
complementarity, which states that objects have certain pairs of
complementary properties which cannot all be observed or measured
simultaneously. Moreover, the act of "observing" or "measuring" an
object is irreversible, and no truth can be attributed to an
object except according to the results of its measurement.
Copenhagentype interpretations hold that quantum descriptions are
objective; in that, they are independent of physicists' mental
arbitrariness.
Over the years, there have been many objections to aspects of
Copenhagentype interpretations, including the discontinuous and
randomness nature of the "observation" or "measurement" process,
the apparent subjectivity of requiring an observer, the difficulty
of defining what might count as a measuring device, and the
seeming reliance upon classical physics in describing such
devices.
The Copenhagen Interpretation is generally accepted by Quantum
Physicists as the proper scientific theory about the Quantum
world. However, it has been challenged by several notable
physicists since its formulation, most notably by Einstein, who
spent the latter part of his life on this challenge. The core
objections to The Copenhagen Interpretation are:
Two Questions about Reality
 Does the natural world exist independently of our minds?
More precisely, does matter have a stable set of properties in
and of itself, without regard to our perceptions and
knowledge?
 Can these properties be comprehended and described by us?
Can we understand enough about the laws of nature to explain
the history of our universe and predict its future?
Two Classes of Interpretation
 The Copenhagen Interpretation is essentially correct
 The Copenhagen Interpretation is incomplete
Two Classes of Quantum Physicists
 AntiRealists  There is no underlying reality of Quantum
Physics
 Realists  Quantum Physics should attempt to explain an
underlying reality
Epistemology and Ontology Impacts
 Epistemology  The philosophical theory of knowledge
 Ontology  The metaphysical study of the nature of being and
existence
Issues to be Resolved
 Nonlocality
 Superposition
 Entanglement
 Measurement
Deterministic vs. Probabilistic Universes
 Deterministic  An inevitable consequence of antecedent
sufficient causes
 Probabilistic  of or relating to the probability of
occurrence
Locality and Universality
 Locality  A particular area; the surrounding or nearby
region
 Universality  The quality of being universal; existing
everywhere
The Two Classes of Interpretation are that if you believe that
the Copenhagen Interpretation is all there is to the Quantum
world, or if you believe that the Copenhagen Interpretation does
not explain the underlying reality of the Quantum world. The Two
Questions about Reality reveal what type of Quantum Physicist you
are. The realists answer yes to these questions, while
antirealists answer no. This reminds me of the two types of
persons in the Harry Potter novels: Muggles (realists) and Wizards
(antirealists). Muggles take the side of Einstein, while Wizards
take the side of Bohr and Heisenberg.
The Copenhagen Interpretation challenges the Ontology of our
universe, as one of its foundations is that reality doesn't exist
until we measure it. This idea led Einstein to ask, "Does the Moon
exist only when someone was looking at it?" This question is at
the heart of the ontological question of the Copenhagen
Interpretation. By not addressing the ontological question, the
Copenhagen Interpretation relies on the Epistemology of Quantum
Physics and responds that the Quantum world is unknowable and,
therefore, need not be examined. Ontological and Epistemological
questions need to be answered by science to understand the reality
of our Universe. By avoiding these questions, the Copenhagen
Interpretation is not meeting the requirements or expectations of
physics to explain the fundamental properties of the Universe.
The Copenhagen Interpretation has four issues that bedevil it
regarding the question of the Copenhagen Interpretation being a
description of reality.
Quantum
nonlocality is a principle in quantum mechanics that says
quantum particles can "know" the states of other quantum
particles, even at great distances, and correlate their behaviors
with each other instantaneously (i.e., instantaneous
actionatadistance). While classical physics assumes locality,
the principle of nonlocality is a feature of many interpretations
of quantum mechanics. Nonlocality appears to be a feature of even
the original interpretation of quantum mechanics, the Copenhagen
Interpretation, though it remains implicit in this interpretation
rather than being explicitly called out. The equations which
describe quantum entanglement seem to tell us that two particles
across the universe from each other can correlate their behavior
simultaneously. Simultaneous is faster than the speed of light,
and lab experiments that demonstrate quantum entanglement have
shown this to be true.
Quantum
superposition is a fundamental principle of quantum
mechanics. It states that, much like waves in classical physics,
any two (or more) quantum states can be added together
("superposed"), and the result will be another valid quantum
state; and conversely, that every quantum state can be represented
as a sum of two or more other distinct states. Mathematically, it
refers to a property of solutions to the Schrödinger
equation; since the Schrödinger equation is linear, any
linear combination of solutions will also be a solution. It is
also the basis for the paradox of Schrödinger's
cat.
Quantum
entanglement is a physical phenomenon that occurs when a
group of particles are generated, interact, or share spatial
proximity in a way such that the quantum state of each particle of
the group cannot be described independently of the state of the
others, including when the particles are separated by a large
distance. The topic of quantum entanglement is at the heart of the
disparity between classical and quantum physics: entanglement is a
primary feature of quantum mechanics lacking in classical
mechanics.
The Measurement
problem is the problem of how or whether wave function collapse
occurs. The inability to observe such a collapse directly has
given rise to different interpretations of quantum mechanics and
poses a key set of questions that each interpretation must answer.
The Quantum nonlocality, Quantum superposition, Quantum
entanglement, and the Measurement problems are often grouped
together as the Copenhagen interpretation are the oldest and,
collectively, probably still the most widely held attitude about
quantum mechanics. N. David Mermin coined the phrase "Shut up and
calculate!" to summarize Copenhagentype views, a saying often
misattributed to Richard Feynman and which Mermin later found
insufficiently nuanced. Shut up and compute is useful to solve
problems in Quantum Physics, but it is not useful in understanding
the underlying reality of the Quantum universe. It was these
problems that led Einstein and other physicists to challenge the
Copenhagen Interpretation as a description of the reality
underlying the Quantum world.
The Heisenberg
uncertainty principle, first introduced in 1927 by the
German physicist Werner Heisenberg, states that the more precisely
the position of some particle is determined, the less precisely
its momentum can be predicted from initial conditions, and vice
versa. The uncertainty principle implies that it is, in general,
not possible to predict the value of a quantity with arbitrary
certainty, even if all initial conditions are specified. In a
Deterministic Universe, if you knew the properties of a starting
point, then the forces acting upon the starting point, you could
then predict the result. In a Probabilistic Universe, you can only
predict possible limited outcomes. General and Special Relativity
observations and experiments indicate that we live in a
Deterministic Universe, while Quantum Physics observations and
experiments have shown that regarding atomic and subatomic
particles, we live in a Probabilistic Universe. It is this
dichotomy that is of concern for modern physics, leading to much
scientific speculation and (heated) debates. The Uncertainty
principle also has a role in determining the underlying reality of
the Quantum world.
The Copenhagen Interpretation deals only with atomic and
subatomic events, but Quantum Physics needs to be reconciled with
Einstein's General and Special Theories of Relativity to be
universal. The Nonlocality of Quantum Physics conflicts with
Special Relativity, and logically you cannot have a universe where
both are true. However, both have been proven to be true, and this
issue needs a resolution to understand the reality of our
universe. In addition, Quantum Physics needs to be reconciled with
the gravity of General Relativity, as gravity in the Copenhagen
Interpretation plays no part in Quantum Physics.
The Loop
quantum gravity interpretation is one of many other
Interpretations that attempt to reconcile Relativity and the
Quantum universe. Loop quantum gravity (LQG) is a theory of
quantum gravity, which aims to merge quantum mechanics and general
relativity, incorporating matter of the Standard Model into the
framework established for the pure quantum gravity case. It is an
attempt to develop a quantum theory of gravity based directly on
Einstein's geometric formulation rather than the treatment of
gravity as a force. As a theory, LQG postulates that the structure
of space and time is composed of finite loops woven into an
extremely fine fabric or network. These networks of loops are
called spin networks. The evolution of a spin network, or spin
foam, has a scale above the order of a Planck length,
approximately 10 to the minus 35 meters, as smaller scales are
meaningless. Consequently, not just matter, but space itself,
prefers an atomic structure.
A good book that is readable and understandable by the general
public, Einstein's
Unfinished Revolution: The Search for What Lies Beyond the
Quantum by Lee
Smolin, looks at these issues and the repercussions of the
possible answers to these questions. Lee Smolin is an American
theoretical physicist, a faculty member at the Perimeter Institute
for Theoretical Physics, an adjunct professor of physics at the
University of Waterloo, and a member of the graduate faculty of
the philosophy department at the University of Toronto. He is also
a Muggle and one of the originators of Loop quantum gravity, but
the book presents a fair and balanced examination between Muggles
and Wizard's viewpoints.
The above issues and questions, along with the correct answers,
needs to be resolved for Physics to make its next great
advancement. These answers will help a great deal in solving
The
18 Biggest Unsolved Mysteries in Physics.
Disclaimer
Please Note  many academics, scientist and
engineers would critique what I have written here as not accurate
nor through. I freely acknowledge that these critiques are
correct. It was not my intentions to be accurate or through, as I
am not qualified to give an accurate nor through description. My
intention was to be understandable to a layperson so that they can
grasp the concepts. Academics, scientists, and engineers entire
education and training is based on accuracy and thoroughness, and
as such, they strive for this accuracy and thoroughness. I believe
it is essential for all laypersons to grasp the concepts of this
paper, so they make more informed decisions on those areas of
human endeavors that deal with this subject. As such, I did not
strive for accuracy and thoroughness, only understandability.
Most academics, scientist, and engineers when speaking or writing
for the general public (and many science writers as well) strive
to be understandable to the general public. However, they often
fall short on the understandability because of their commitment to
accuracy and thoroughness, as well as some audience awareness
factors. Their two biggest problems are accuracy and the audience
knowledge of the topic.
Accuracy is a problem because academics, scientist, engineers and
science writers are loath to be inaccurate. This is because they
want the audience to obtain the correct information, and the
possible negative repercussions amongst their colleagues and the
scientific community at large if they are inaccurate. However,
because modern science is complex this accuracy can, and often,
leads to confusion amongst the audience.
The audience knowledge of the topic is important as most modern
science is complex, with its own words, terminology, and basic
concepts the audience is unfamiliar with, or they misinterpret.
The audience becomes confused (even while smiling and lauding the
academics, scientists, engineers or science writer), and the
audience does not achieve understandability. Many times, the
academics, scientists, engineers or science writer utilizes the
scientific disciplines own words, terminology, and basic concepts
without realizing the audience misinterpretations, or has no
comprehension of these items.
It is for this reason that I place understandability as the
highest priority in my writing, and I am willing to sacrifice
accuracy and thoroughness to achieve understandability. There are
many books, websites, and videos available that are more accurate
and through. The subchapter on “Further Readings” also contains
books on various subjects that can provide more accurate and
thorough information. I leave it to the reader to decide if they
want more accurate or through information and to seek out these
books, websites, and videos for this information.
© 2023. All rights reserved.
If you have any comments, concerns, critiques, or suggestions I
can be reached at mwd@profitpages.com.
I will review reasoned and intellectual correspondence, and it
is possible that I can change my mind,
or at least update the content of this article.
