Описание:The course constitutes an introduction into field theory aimed at training hand-on skills of calculations of effects studied in modern high-energy physics on simplified examples. Along with classical topics (Lagrange formalism in field theory, Noether's theorem, radiation theory, Green's functions, relativistic spinors, etc.), the course includes a hand-on session featuring neutrino oscillations, dispersive media, Casimir effect, and others. The first term is given in the language that makes seamless a switch to the quantum field theory in the second term. The second term of the course also includes a theorist's introduction into group theory and representations.