Threads
Eight concepts that recur across the whole degree. Where the curriculum moves forward unit by unit, a thread cuts sideways — follow one to watch a single idea deepen, break, and reform as the physics gets harder.
Force
Newton's second law as a definition, then a bookkeeping fiction as forces dissolve into fields, and finally the curvature of spacetime in general relativity. Newton → fields → curvature.
Energy
A conserved quantity born from time-translation symmetry, constrained by the Carnot bound on what heat can do, then counted statistically by the Boltzmann distribution. Time-symmetry → Carnot → Boltzmann.
Light
Rays and lenses in geometric optics, unified as oscillating electromagnetic waves by Maxwell, then quantised into photons that arrive one at a time. Optics → EM → photons.
Matter
Ideal gases described by bulk laws, explained by the statistics of many particles, then organised into the band structure of solids. Gases → statistics → solids.
Waves
Simple oscillation, superposed into localised wave packets, then the quantum tunnelling that lets a packet leak through a barrier it classically cannot cross. Oscillation → packets → tunnelling.
Fields
Scalar potentials, promoted to a Lagrangian density whose variations give the dynamics, then quantised into the excitations of quantum field theory. Potential → Lagrangian → QFT.
Chance
Classical probability, sharpened into the entropy that counts microstates, then confronted with the measurement problem where amplitudes become outcomes. Probability → entropy → measurement.
Symmetry
Noether's theorem tying each symmetry to a conservation law, extended to the local gauge symmetries behind the forces, closing the loop back to conservation. Noether → gauge → conservation.
Each thread page is a guided path — a sequence of derivations and lectures drawn from across the curriculum, annotated to show the same idea returning at greater depth. Start anywhere; the threads all eventually meet.