# hw308 - Classical Electrodynamics Physics 6561 Homework 3...

This preview shows pages 1–2. Sign up to view the full content.

Classical Electrodynamics Physics 6561 Homework 3. Due: In class on Tuesday, 9/23 1. Force of charged particle with constant velocity (5 points) Two equal charges q move with equal velocity ~v . What is the force acting between the two charges? The distance between the two charges is R and the angle between ~v and ~ R is θ . 2. Gauge invariance of interacting Lagrangian (5 points) We have made the gauge invariance one of the basic principles for writing down the Maxwell Lagrangian. Argue, that the interaction described by the usual Lagrangian L int = - 1 c 2 A μ j μ is also gauge invariant. 3 Scalar ﬁeld theory in 2-D (10 points) Consider a real scalar ﬁeld φ in 2 dimensions, described by the Lagrangian density L = 1 2 μ φ∂ μ φ - λ ( φ 2 - φ 2 0 ) 2 . (a) Derive the Euler-Lagrange equation of motion for this ﬁeld, and the symmetric energy- momentum tensor. The energy momentum tensor is deﬁned as T μν = L ∂∂ μ φ ν φ - g μν L . (b) Find an explicit STATIC solution (eg.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.
• Fall '08
• LIPSON/POLLOCK
• Fundamental physics concepts, Energy density, Noether's theorem, Lagrangian density, Proca Lagrangian density, usual Lagrangian Lint

{[ snackBarMessage ]}

### Page1 / 2

hw308 - Classical Electrodynamics Physics 6561 Homework 3...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online