Electrodynamics: Dance of Fields
Electrodynamics in 22 chapters — from “Coulomb’s Law and the Electrostatic Field” to “Radiation from Arbitrary Charge Motion: Liénard-Wiechert Fields and Beyond”.
Chapters
- Coulomb’s Law and the Electrostatic Field
- Charge as a conserved quantity: the empirical facts
- Coulomb’s law and the superposition principle
- The electric field: from calculational convenience to physical object
- Gauss’s law in integral form
- Visualizing field lines and flux
- Summary and forward view
- Problems
- Selected solutions
- Electrostatic Potential and Energy
- The curl-free nature of electrostatic fields
- Potential of point charges and continuous distributions
- Equipotentials and the geometry of potential
- Electrostatic energy: from pairs to fields
- The uniqueness theorem and boundary-value problems
- Summary and forward view
- Problems
- Selected solutions
- Solving Laplace and Poisson: Method of Images and Separation
- The method of images: exploiting symmetry and uniqueness
- Images in spheres and cylinders
- Separation of variables in Cartesian coordinates
- Spherical harmonics and multipole expansions
- Summary and forward view
- Problems
- Selected solutions
- Conductors, Capacitance, and Dielectrics
- Electrostatic boundary conditions at conductor surfaces
- Capacitance: definition, calculation, and energy storage
- Polarization and the bound charge density
- The displacement field D and Gauss’s law in matter
- Linear dielectrics and the permittivity
- Summary and forward view
- Problems
- Selected solutions
- Currents, Ampère's Law, and the Magnetostatic Field
- Current density and the continuity equation
- The Biot–Savart law
- Ampère's law
- The vector potential
- Magnetic field lines, flux, and the absence of magnetic charge
- Summary and forward view
- Problems
- Selected solutions
- Magnetic Forces and the Lorentz Force Law
- The Lorentz force
- Motion in uniform fields: the cyclotron and the drift
- Force and torque on current loops
- Magnetic energy and inductance
- Summary and forward view
- Problems
- Selected solutions
- Magnetic Materials: Ferromagnetism and the H Field
- Magnetisation and bound currents
- The auxiliary field H and Ampère's law in matter
- Linear magnetic materials: permeability μ
- Ferromagnetism, hysteresis, and permanent magnets
- Summary and forward view
- Problems
- Selected solutions
- Faraday's Law and Electromagnetic Induction
- Faraday's experiments and the flux rule
- From flux rule to the differential law
- Lenz's law and the minus sign
- Motional EMF and the two-mechanisms puzzle
- Mutual inductance and the transformer
- Summary and forward view
- Problems
- Selected solutions
- Maxwell's Displacement Current and the Complete Equations
- The crack in Ampère's law
- Maxwell's fix
- The Maxwell equations
- Potentials and gauge freedom
- A glimpse of waves
- Summary and forward view
- Problems
- Selected solutions
- Conservation Laws: Energy, Momentum, and the Stress Tensor
- Poynting's theorem: energy flow in the fields
- Visualising energy flow: the Poynting vector in circuits and radiation
- Momentum density and the Maxwell stress tensor
- Radiation pressure and the Abraham-Minkowski controversy
- Summary and forward view
- Problems
- Selected solutions
- Plane Waves in Vacuum: The Simplest Radiative Solution
- The wave equation and the plane-wave ansatz
- Transversality: E, B, and k form a right-handed triad
- Polarization: linear, circular, elliptical
- Energy and momentum in a plane wave
- Summary and forward view
- Problems
- Selected solutions
- Waves in Matter: Dispersion, Absorption, and the Refractive Index
- Maxwell's equations in a linear medium, and what the constitutive relations conceal
- Plane waves in a medium: complex permittivity, complex wave number, complex index
- Where dispersion comes from: the Lorentz oscillator
- Normal and anomalous dispersion, transparency windows, and conductors
- Phase, group and signal velocity, and the Kramers–Kronig relations
- Energy and momentum in a dispersive medium
- Stokes parameters: what matter does to polarization
- Summary and forward view
- Problems
- Selected solutions
- Reflection and Refraction: Fresnel Equations and Brewster's Angle
- Boundary conditions at a dielectric interface
- Snell's law and the geometry of refraction
- Fresnel equations for s and p polarisation
- Brewster's angle and total internal reflection
- Summary and forward view
- Problems
- Selected solutions
- Guided Waves and Resonant Cavities
- Boundary conditions at a perfect conductor
- TE and TM modes in a rectangular waveguide
- Dispersion in waveguides: ω(k) and group velocity
- Resonant cavities: standing waves and the quality factor
- Summary and forward view
- Problems
- Selected solutions
- Retarded Potentials and the Inhomogeneous Wave Equation
- The inhomogeneous wave equations for φ and A
- Green's function and retarded potentials
- The Liénard-Wiechert potentials for a moving point charge
- Near, intermediate, and far zones
- Summary and forward view
- Problems
- Selected solutions
- Electric Dipole Radiation: The Simplest Radiator
- The oscillating dipole and its retarded potential
- Radiation fields: the 1/r transverse wave
- Angular distribution and the sin2θ pattern
- Total radiated power: the Larmor formula
- Summary and forward view
- Problems
- Selected solutions
- Magnetic Dipole and Electric Quadrupole Radiation
- The magnetic dipole: an oscillating current loop
- Power radiated by a magnetic dipole
- Electric quadrupole radiation: the next multipole
- The multipole hierarchy and selection rules
- Summary and forward view
- Problems
- Selected solutions
- Antennas and Arrays: Engineering Radiation Patterns
- The half-wave dipole antenna
- Antenna arrays and interference
- Phased arrays and beam steering
- Reciprocity: antennas as transmitters and receivers
- Summary and forward view
- Problems
- Selected solutions
- Special Relativity: Spacetime, Lorentz Transformations, and Four-Vectors
- Einstein's 1905 postulates and the Lorentz transformation
- Spacetime diagrams and the invariant interval
- Four-vectors: position, velocity, momentum, and current
- Tensors and the metric: raising and lowering indices
- Summary and forward view
- Problems
- Selected solutions
- The Electromagnetic Field Tensor and Covariant Maxwell Equations
- Constructing Fμν from E and B
- Lorentz transformation of fields: E and B mix
- The covariant Maxwell equations
- Invariants: E · B and E2−c2B2
- Summary and forward view
- Problems
- Selected solutions
- Relativistic Particle Dynamics in Electromagnetic Fields
- The Lorentz force in covariant form
- Motion in constant uniform fields
- Radiation from accelerated charges: the Larmor formula generalized
- Synchrotron radiation: the ultra-relativistic regime
- Summary and forward view
- Problems
- Selected solutions
- Radiation from Arbitrary Charge Motion: Liénard-Wiechert Fields and Beyond
- The Liénard-Wiechert fields: exact E and B
- The velocity fields: the Coulomb field boosted
- The acceleration fields: the radiation term
- Beaming and the radiation reaction force
- Coda: the classical electron radius and the limits of classical theory
- Summary and forward view
- Problems
- Selected solutions