Centre for Continuing Education

Philosophy for Science Course IV: Where Classical Physics Ends and Quantum Mechanics Begins

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Science is a ‘methodology’: a particular way of observing and explaining the world, of answering the one big question: “What must the world be like, that it produce the phenomena we observe?” This course is the final part a four part Philosophy for Science series which explores why, around the turn of the twentieth century, classical “Newtonian” mechanics gave way to a completely new paradigm: Quantum Mechanics (QM). In this course, we review some of the experimental phenomena that Classical Mechanics simply cannot explain; we define QM and elaborate its various (mis)interpretations; dismantle much of the nonsense that is attributed to it in the popular literature; and explore why even QM struggles to describe what the world is really like.

This course is part of a series and should ideally be completed in sequence.

Course content

This philosophy of science course covers the following topics:

Introduction: Review of the Nature of Observation

  • Science as the project to describe how the world appears to be
  • Observation as interpretation of local tripartite interactions
  • Event-based ontology: entities as inference from observation and data integration
  • Observables, beables and/or “behavables”
  • Practical and theoretical limits to observability: granularity, frame/flicker effect
  • Uncertainty: definite vs indefinite states-of-affairs
  • Epistemic and ontological indeterminability vs ontological indeterminacy
  • Haecceity (“thisness”) and quiddity (“whatness”)
  • The Ship of Theseus
  • The ‘minimum’ explanation: dynamism, heterogeneity, corpuscularity, finitude, emergence, feedback, complexity and chaos
  • Description vs explanation: descriptive, explanatory, and predictive power

Review of Classical Mechanics

  • Frames of reference
  • Dimensionality of spacetime
  • Simultaneity
  • The “Entity-State-Event” model of change: Least Action, causation and determinability
  • Lagrangian vs Hamiltonian mechanics
  • Macro-molecular, molecular, atomic and sub-atomic structure
  • The size of atoms and particles
  • Infinite divisibility
  • Brownian motion
  • Inertia and Energy; Disequilibrium and Force
  • Kinetic, potential and radiant energy
  • Conservation Laws
  • Heat and pressure as vibrational kinetic energy
  • Maxwell’s kinetic theory; thermodynamics
  • Ludwig Boltzmann’s 'statistical mechanics'
  • Equipartition of energy
  • Circular motion
  • Simple harmonic motion
  • Weight on a spring
  • Swing of a pendulum
  • Waves in a string and other elastic media
  • Stationary waves.

Review of Electromagnetism and Light

  • Electrostatic charge
  • Magnetism
  • Electrical and magnetic induction
  • Light as electromagnetic radiant energy
  • Maxwell’s equations, the speed of light
  • The propagation of light through different media
  • Refraction, Reflection, thin films
  • The luminiferous aether, & the Michelson-Morley experiment
  • Gravity
  • The speed of gravity
  • Gravity waves and gravitational lensing
  • The Doppler effect
  • Red- and blue-shifts
  • Colour, absorption and emission spectra, the Balmer Series, spectroscopy
  • Young’s ‘double-slit’ experiment (with light)

Apparent Quantisation in Light/Matter Interactions

  • The photoelectric effect
  • Black body radiation: Wien’s Law, Rayleigh-Jeans Law, Planck’s Law
  • Young’s ‘double-slit’ experiment (with particles)
  • Wheeler’s delayed-choice experiment
  • Propagation of energy and momentum, radiation pressure, the Casimir effect
  • The Compton Effect
  • The wave/particle duality of light and matter - "Wavicles"
  • Heisenberg’s Uncertainty Principle
  • Indeterminacy vs indeterminability
  • Niels Bohr’s Complementarity

The Quantisation of Matter

  • Rutherford’s diffraction experiments
  • Bohr’s model of the atom
  • Explanation of the Balmer series
  • Quantum Numbers
  • Matter/anti-matter creation/annihilation
  • Matter waves, de Broglie’s symmetry: E=mc2=hf

The Quantisation of Forces and Energy

  • Fundamental forces: electromagnetism, weak & strong nuclear forces, and gravity
  • Evidence from chemistry – radioactive isotopes, semiconductors, superconductors
  • Electron microscopy, NMR, nuclear fission and fusion
  • Forces as particles (bosons) – photon, meson, gluon, graviton; and the Higgs boson
  • Quarks & the zoo of ‘fundamental’ particles – the “Standard Model”
  • Magnetic moments and angular momentum
  • Stern-Gerlach experiments

Quantum Mechanics

  • Transformation matrices
  • Paul Dirac’s 'matrix algebra'
  • Max Born’s 'matrix mechanics'
  • Erwin Schrödinger’s wave equation, and 'wave mechanics'
  • Max Born’s probability interpretation
  • The “Copenhagen” interpretation: superposition, entanglement, decoherence
  • Schrödinger’s Cat and the "measurement problem"
  • Non-Locality
  • Bell’s Inequalities
  • The Aspect experiments
  • “Hidden variable” and “non-locality” interpretations
  • The EPR experiment
  • John Wheeler’s advance wave theory
  • Backward causation
  • Mach-Zehnder interferometry

More Quantum Mechanics, and Beyond

  • Conservation Laws: Invariance, symmetry, supersymmetry, CPT invariance
  • Gauge theories, group theories, GUTs and ToEs
  • QED – Quantum Electro-Dyamics
  • QCD – Quantum Chromo-Dyamics
  • QFD – Quantum Field Dyamics
  • String theory; Superstring theory
  • Branes, and M-theory
  • Loop quantum gravity
  • Multi-dimensional spacetime
  • Light envelopes
  • Black Holes; parallel/multiple universes; wormholes; time travel; and teleportation
  • The expanding Universe – Hubble’s Constant – Big Crunch or Big Chill?
  • The return of the aether: a quantum field filled with dark energy and dark matter
  • The future
  • The limits of scientific inquiry; and what it is possible/impossible to know

Course outcomes

By the end of this philosophy of science course, participants should be familiar with:

  • The implications for Classical Physics of the difference between “observables” and "beables"
  • The non-Classical nature of phenomena on the quantum scale
  • The apparent quantisation and dual wave/particle nature of observables
  • The interpretation of Quantum Mechanics as a theory of observables
  • The language of Quantum Mechanics
  • What QM does, does not, and cannot tell us about the nature of the physical world

Course suitable for

This course is the final Part of a four part series entitled "Philosophy for Science: Understanding the Physical World", and much of its content relies on material covered in earlier parts. Participants with no experience in Physics are urged to complete those earlier parts before embarking upon this course. That said, this course assumes only high-school mathematics and physics, and a keen, inquiring mind!

Course reading

The following readings are recommended, but not required:

  • Albert, David Z., Quantum Mechanics and Experience, Harvard University Press, 1994
  • Barrow, John D., Impossibility, London: Vintage, 1999
  • Bell, John S., Speakable and Unspeakable in Quantum Mechanics, Cambridge University Press, 1988
  • Briggs, J. P. and Peat, F. D., Looking Glass Universe – The Emerging Science of Wholeness, London: Fontana, 1985
  • Calder, Nigel, Einstein’s Universe – The Layperson’s Guide, London: Penguin, 1990
  • Chalmers, Alan F., What Is This Thing Called Science?, 3rd Ed., Qld University Press, 2000
  • Davies, Paul, Superforce, London: Unwin, 1986
  • Davies, Paul, Other Worlds, London: Penguin, 1990
  • Davies, Paul, The Last Three Minutes, London: Phoenix, 1994
  • Deutsch, David, The Fabric of Reality, Penguin, 1998
  • Einstein, Albert, Relativity: The Special and the General Theory, New York: Three Rivers Press, 1961
  • Feynman, Richard P., QED: The Strange Theory of Light and Matter, Princeton University Press, 2006
  • Feynman, Richard P., Six Easy Pieces, Basic Books, 2005
  • Feynman, Richard P., Six Not So Easy Pieces, Basic Books, 1998
  • Gell-Man, Murray, The Quark and the Jaguar, London: Abacus, 1995
  • Gleick, James, Chaos, London: Macdonald & Co., 1987
  • Greene, Brian, The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory, Vintage, 2000
  • Greene, Brian, The Fabric of the Cosmos: Space, Time and the Texture of Reality, Allen Lane/Penguin, 2004
  • Gribbin, John, In Search of Schrödinger’s Cat, London: Corgi, 1985
  • Gribbin, John, Q is for Quantum: Particle Physics from A to Z, London: Phoenix, 1998
  • Hawking, Stephen, A Brief History of Time, London: Bantam, 1988
  • Hawking, Stephen, The Universe in a Nutshell, London: Bantam, 2001
  • Maddox, John, What Remains to be Discovered, London: Macmillan, 1998
  • Prigogine, Ilya; and Stengers, Isabelle, Order out of Chaos, London: Flamingo, 1988
  • Orzel, Chad, How to Teach Physics to a Dog, Scribner, 2009
  • Penrose, Roger, The Road To Reality: A Complete Guide to the Laws of the Universe, London: Vintage, 2005
  • Quinton, Anthony, The Nature of Things, Routledge, 1980
  • Reichenbach, Hans, The Philosophy of Space and Time, New York: Dover, 1958
  • Resnick, Robert and Halliday, David, Physics: Parts I and II, John Wiley & Sons, 1966
  • Smolin, Lee, The Trouble With Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next, Allen Lane, 2006
  • Weinberg, Steven, Dreams of a Final Theory, London: Vintage, 1993
  • Woit, Peter, Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law, Basic, 2006


  • Expert trainers
  • Central locations
  • Small class sizes
  • Free, expert advice
  • Student materials – yours to keep
  • Statement of completion

What others say.

  • Content of this course is fascinating and concise.

  • I thoroughly enjoyed Philosophy for Science I, II, III and IV. The tutor’s knowledge of their subject is both deep and wide. Their enthusiasm for it is sincere. Their presentation of it is engaging, and they get everyone in the class involved with questions and discussions. The Philosophy for Science courses provide a fascinating and thought-provoking perspective.