Contents › Part 9

Part 9 — Quantum Mechanics

1. The Postulates of Quantum Mechanics
   • The conventional postulates
   • Density-matrix postulates
   • On Planck's constant
   • Pictures of time evolution
   • Canonical quantization rules
   • The Heisenberg uncertainty principle
2. Elementary Quantum Systems
   • The free particle
   • Potential wells
   • Tunnelling
   • The harmonic oscillator
   • Periodic potentials: a preview
3. Angular Momentum and Spin
   • The angular-momentum algebra
   • Orbital angular momentum
   • Spin
   • Addition of angular momenta
   • Tensor operators and the Wigner–Eckart theorem
   • Spin dynamics and magnetic resonance
4. Experiment: Stern–Gerlach experiment
   • Historical context, 1921–1922
   • Stern–Gerlach (1921–1922)
   • The phenomenon: space quantization
   • Sequential Stern–Gerlach experiments
   • Legacy
5. The Hydrogen Atom
   • The spectrum before the theory
   • The exact solution
   • Degeneracy and the hidden symmetry
   • Fine and hyperfine structure
   • The 21-centimetre line
   • Precision hydrogen and the constants
   • Hydrogen-like systems
6. Approximation Methods
   • Stationary perturbation theory
   • Perturbation theory at work
   • The variational method
   • The semiclassical approximation
   • Time-dependent perturbation theory
   • Adiabatic and sudden limits
7. Identical Particles
   • Indistinguishability and the exchange operator
   • Bosons and fermions
   • Constructing many-particle states
   • The exchange interaction
   • The spin–statistics connection
   • Two-particle interference
   • Consequences for bulk matter
8. Entanglement and Bell Tests
   • Entangled states
   • The EPR argument and the replies
   • Bell's theorem
   • What entanglement may not do
   • Quantifying entanglement
   • Entanglement as a resource
   • The experimental record
9. Interpretations (Evidence-Anchored)
   • The measurement problem
   • What experiment has already settled
   • The interpretive programmes
   • Dynamical collapse: interpretation made testable
   • Adjacent experiments that constrain the discussion
   • The ledger
10. Scattering Theory
    • What a scattering experiment measures
    • The stationary formulation
    • Partial waves and phase shifts
    • The S-matrix
    • Resonances
    • Coulomb scattering
    • Observed effects the formalism must reproduce
11. Open Quantum Systems and Decoherence
    • States of an open system
    • Quantum channels
    • Master equations
    • Decoherence
    • Decoherence observed
    • The quantum Zeno effect
    • Fighting decoherence
12. Atoms and Molecules
    • The many-electron problem
    • Self-consistent field theory
    • The Thomas–Fermi model
    • The periodic table
    • Angular-momentum coupling
    • The Born–Oppenheimer separation
    • The chemical bond
    • Molecular spectra
    • Intermolecular forces
13. Experiment: Bell Tests experiment
    • Historical context and the prediction under test
    • Apparatus
    • Procedure
    • Observations
    • Interpretation
    • Modern repetitions and precision
14. Experiment: Precision Spectroscopy and Atomic Clocks experiment
    • Historical context and the prediction under test
    • Apparatus
    • Procedure
    • Observations
    • Interpretation
    • Modern repetitions and precision
15. Experiment: Quantum Tunnelling Observed experiment
    • The prediction under test
    • Alpha decay and the Geiger–Nuttall relation (1911, 1928)
    • Fowler and Nordheim: cold field emission from metals (1928)
    • Esaki: the tunnel diode and negative differential resistance (1958)
    • Giaever: tunnelling spectroscopy of the superconducting gap (1960)
    • Binnig and Rohrer: the scanning tunnelling microscope (1982)
    • Summary of the evidence