Paradigm Shift Outline

Posting online removed my bullets and indents, but hopefully the outline can still be followed.

Thesis:  The shift from classical to quantum physics, as expressed by the Heisenberg Uncertainty Principle and the Copenhagen Interpretation of quantum mechanics, has had wide philosophical ramifications and has resulted in a paradigm shift in how we view objectivity.

Classical Physics:

Explain what it meant by “classical physics”

Predates more complete or widely accepted “modern” theories of physics

Includes many branches

Classical mechanics

Includes the work of Newton and others

Classical electrodynamics

Classical thermodynamics

Relativity

Classical physics itself represents a major paradigm shift:

Classical physics describes a universe bound by natural laws described through mathematics

Belief in a rational and mathematical order of the universe spread and emphasis on reason began to overtake tradition

Classical theories of physics accurately apply only to relatively large and slow objects

Can still apply to objects that we think of as very small or very fast in terms of our everyday experience

perhaps include numerical scales, perhaps not (scientific notation of very large or very small numbers are difficult to picture in the mind and may be more clunky than helpful to the reader)

Classical models break down when applied to very small or very fast objects, therefore they are not fundamental

Although only conditionally true, classical physics can be extremely useful in describing the world as humans experience it.  Because of their usefulness, it can be tempting to think of classical models as THE way the universe works.

Ontological Principles of Classical Physics:

Classical physics has influenced our metaphysical understanding of existence and reality.  Many of these ontological principles feel like formalized statements of common sense (these statements, however, are challenged by quantum mechanics).

Principles of physical objects and identity

Physical objects exist in space and time and physical processes take place in space and time

Physical objects are localizable

That is, they do not exist everywhere in space and time.  They are confined to a definite time and place.

A particular place can only be occupied by one object of the same kind at a time

Two physical objects of the same kind exist separately

That is, not at the same place at the same time

Physical objects are countable

The principle of separated properties

The principle of value determinateness

The principle of causality

The principle of determination

The principle of continuity

The principle of the conservation of energy (above principles from Faye)

Focus on the principles of causality, determination, and continuity because of how important they are in how we make sense of the world

Discuss Immanuel Kant

“Much of Kant’s philosophy can be seen as an attempt to provide satisfactory philosophical grounds for the objective basis of Newton’s mechanics against Humean scepticism.  Kant thus argued that classical mechanics is in accordance with the transcendental conditions for objective knowledge.” (Faye)

Kant’s philosophy undoubtedly influenced Niels Bohr (a pioneer in quantum mechanics and one of the founding fathers of the Copenhagen interpretation of quantum mechanics)

Discuss the importance of language as the lens through which we interpret and describe reality (as described by Kant and Bohr).  Basic concepts, reflected in our language, such as “space”, “time”, “causation” and “continuity” exist already in our minds and are preconditions of any unambiguous and meaningful communication.

“So, in Bohr’s opinion the conditions for an objective description of nature given by the concepts of classical physics were merely a refinement of the preconditions of human knowledge.” (Faye)

Explanation of the Heisenberg Uncertainty Principle:

Not sure of how technical or in depth I want to get in explaining the Heisenberg Uncertainty Principle.  I’ll try out different levels of detail and try to gauge what feels right.  The focus of my paper is the broader implications of the Heisenberg Uncertainty Principle and quantum mechanics, so I want to avoid getting bogged down in technical explanations.  At the same time, it is necessary to be familiar with the physics to a certain degree in order to understand the conclusions drawn from it.  The following is the basics of what I would include.

The Heisenberg Uncertainty Principle is often invoked outside of its context in physics (sometimes incorrectly)

Science educator, Hank Green, hosts a section comically named IDTTMWYTIM on his science show.  This stand for “I Don’t Think That Means What You Think It Means”.  In one edition, he explains the Heisenberg Uncertainty Principle.

“The Uncertainty Principle was first proposed in 1927 by German physicist, Werner Heisenberg, who was trying to figure out… how to determine the exact location of an electron orbiting the nucleus of an atom.” (Green)

What Heisenberg discovered… is that it’s impossible to know with certainty both the momentum of an electron, or any subatomic particle, and its exact position, and the more you know about one of these variables the harder it gets to precisely measure the other one.” (Green)

This imprecision is not due to limits in current technology.  It represents a fundamental limitation of our ability to know the properties of a particle.  No improvement in technology could overcome this barrier and allow for a more complete picture.

The Heisenberg Uncertainty Principle is represented by this equation (I’ll try to get it to format nicely in Pages (Khan Academy):

IMG_3123

Explanation of the Copenhagen Interpretation:

“It [quantum mechanics] seems to violate some fundamental principles of classical physics, principles that eventually have become a part of western common sense since the rise of the modern worldview in the Renaissance.  The aim of any metaphysical interpretation of quantum mechanics is to account of these violations.” (Faye)

“The Copenhagen interpretation was the first general attempt to understand the world of atoms as this is represented by quantum mechanics.  The founding father was mainly the Danish physicist Niels Bohr, but also Werner Heisenberg, Max Born and other physicists made important contributions to the overall understanding of the atomic world that is associated with the name of the capital of Denmark.” (Faye)

“The essential controversial features of the Copenhagen Interpretation are (1) the Uncertainty Principle (also called the Indeterminacy Principle) of Heisenberg and (2) the Principle of Complementarity of Bohr.” (Best)

The Copenhagen interpretation presents a less certain world than classical physics.

“Heisenberg’s Principle is also explained by the fact that quantum particles don’t really have a specific position at any given time.  Rather, they exist as what is called a ‘cloud of probability’.” (Green)

This violates one of the ontological principles of classical physics which is that a physical object occupies a single place at any given time.

Another main distinction made between classical and quantum models is that in classical physics the observation of a system does not affect its behavior, or if observation should somehow influence its behavior, it is always possible to incorporate the affect into the prediction of how a system should act.  An extremely simple example is taking the pressure of a tire.  Using a tire gauge lets out a small amount of air from the tire, thus changing the pressure.  However, it is possible to know how much air is leaving through the gauge and account for it.  Faye sums this up well “Thus, in classical physics we can always draw a sharp distinction between the state of the measuring instrument being used on a system and the state of the physical system itself. It means that the physical description of the system is objective because the definition of any later state is not dependent on measuring conditions or other observational conditions.”  Quantum observations do not behave like this.  The act of observation fundamentally alters the system.  Thus, true objectivity is made impossible.

While it may be based upon a subtle point, this limit on objective observation has had a powerful impact.  Science is based upon trying to construct an objective view of the universe, and the Copenhagen interpretation holds that this is impossible.  We were previously limited by our lack of knowledge and technology, but we always had faith that there was an objective universe to observe and that through improvements in technology we could come to know its secrets.  Now this faith has been shaken.

The Heisenberg Uncertainty Principle was discovered in the 1920’s.  This was a culturally tumultuous time in which many of our societal mores were being questioned.  Many people, most influentially artists and intellectuals, were “lost” in the post-war era.  There was a great feeling of uncertainty, and trust in the progress of civilization was shaken by the brutality of the Great War.  The revolutionary advances brought by quantum mechanics gave hard evidence for the limitations of science and reinforced the trend towards subjectivity which was already being driven by emotion.

Works Cited

Best, Ben. “The Copenhagen Interpretation of Quantum Mechanics.” The World of Ben Best. Ben Best, n.d. Web. 26 Oct. 2015.

Faye, Jan. “Copenhagen Interpretation of Quantum Mechanics.” The Stanford Encyclopedia of Philosophy. Stanford University, 03 May 2002. Web. 23 Oct. 2015.

Green, Hank. “IDTIMWYTIM: Heisenberg Uncertainty Principle.” YouTube. SciShow, 14 June 2012. Web. 23 Oct. 2015.

Morin, David. “Introduction to Quantum Mechanics.” A Course in Mechanics An Introduction to Mathematical Modeling (2011): 93-113. Harvard.edu. Harvard University. Web. 26 Oct. 2015.

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