Classical field theory of a massive spin-1 field A^μ with ℒ = −(1/4) F^{μν} F_{μν} + ½ m² A^μ A_μ. Breaks U(1) gauge invariance explicitly.
Classical field theory of a massive spin-1 field A^μ with ℒ = −(1/4) F^{μν} F_{μν} + ½ m² A^μ A_μ. Breaks U(1) gauge invariance explicitly.