Physics / advanced
From fields to quantum fields
Construct quantum fields and connect them to interactions, propagators, and scattering.
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Module 01 advanced
From fields to quantum fields
Construct quantum fields and connect them to interactions, propagators, and scattering.
- 01
Action and Noether’s theorem
Turn continuous global symmetries into conserved currents, while keeping boundary terms and on-shell assumptions visible.
24 min - 02
Classical fields, initial data, and waves
Derive the Klein–Gordon equation and distinguish phase velocity, group velocity, energy, and causal initial-value evolution.
23 min - 03
Quantizing the scalar field
Build a Fock space from oscillator modes and distinguish particles, field operators, vacuum fluctuations, and classical waves.
27 min - 04
Propagators and causal influence
Distinguish time-ordered correlations, retarded response, and spacelike commutativity without treating internal lines as signals.
27 min - 05
Interactions and perturbation theory
Build the Dyson expansion, test what a small coupling really controls, and separate amplitudes from probabilities.
26 min - 06
Feynman rules as an amplitude language
Translate a specified Lagrangian into algebra, track combinatorics, and distinguish a graph from an observed sequence of events.
28 min - 07
From scattering amplitudes to cross sections
Connect asymptotic particle states to measurable rates through flux, phase space, and identical-particle counting.
29 min - 08
Dirac fields and fermionic excitations
Relate spinor equations to relativistic dispersion, antiparticles, and the anticommutation algebra behind Pauli exclusion.
29 min - 09
Gauge fields and quantum electrodynamics
Build a gauge-invariant matter coupling and separate redundant potentials from physical electromagnetic observables.
29 min - 10
Path integrals and generating functions
Build the sum-over-histories viewpoint with a regulator, connect sources to correlations, and identify what the formal notation does not prove.
30 min