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MAU34401 Classical field theory

Module Code MAU34401
Module Title Classical field theory
Semester taught Semester 1
ECTS Credits 5
Module Lecturer Prof. Andrei Parnachev
Module Prerequisites MAU23402 Advanced classical mechanics II

Assessment Details

  • This module is examined in a 2-hour examination at the end of Semester 1.
  • Continuous assessment contributes 20% towards the overall mark.
  • Any failed components are reassessed, if necessary, by an exam in the reassessment session.

Contact Hours

11 weeks of teaching with 3 lectures per week.

Learning Outcomes

On successful completion of this module, students will be able to

  • Apply standard methods to solve problems in electrostatics and magnetostatics.
  • Describe how to find the equation of motion for a scalar field using a given Lagrangian density.
  • Calculate the stress tensor and evaluate its divergence, relating it to a conservation law.
  • Employ a variational principle to find the relativistic dynamics of a charged particle interacting with an electromagnetic potential.
  • Use the Euler-Lagrange equation to show how a Lorentz scalar Lagrangian density with an interaction term leads to the Maxwell equations.
  • Explain the concepts of gauge invariance and traceless tensor in the context of the stress tensor of a vector field.
  • Demonstrate how the divergence of the symmetric stress tensor is related to the four-current density of an external source.

Module Content

  • Electrostatics, Green's theorem, solution using Green functions.
  • Spherically symmetric problems, magnetostatics.
  • Maxwell equations, gauge invariance, transformation properties.
  • Lorentz invariance; scalar, vector and tensor representations.
  • Hamilton variational principle, Lagrangian for relativistic particle.
  • Lorentz force, charged particle interaction, antisymmetric field tensor.
  • Covariant field theory, tensors, scalar fields and the four-vector potential.
  • Lagrangian density for a free vector field, symmetry properties.
  • Canonical stress tensor; conserved, traceless and symmetric stress tensor.
  • Particle and field energy-momentum and angular momentum conservation.

Recommended Reading

  • Classical electrodynamics by J. David Jackson.
  • Classical theory of fields by Landau and Lifshitz.
  • Classical field theory by Francis E. Low.