# Special Relativity and Electrodynamics Spring, 2012

In 1905, while only twenty-six years old, Albert Einstein published "On the Electrodynamics of Moving Bodies" and effectively extended classical laws of relativity to all laws of physics, even electrodynamics. In this course, we will take a close look at the special theory of relativity and also at classical field theory. Concepts addressed here will include four-dimensional space-time, electromagnetic fields, and Maxwell's equations.  (Image credit: KIPAC at Stanford University)

## Lectures in this Course

1. ### The Lorentz transformation

In the first lecture of the course Professor Susskind introduces the original principle of relativity - also known as Galilean Invariance - and discusses inertial reference frames and simultaneity. He then derives the Lorentz transformation of... [more]

Professor Susskind starts with a brief review of the Lorentz transformation, and moves on to derive the relativistic velocity addition formula. He then discusses invariant intervals, proper-time and distance, and light cones. Note: this is only a 1... [more]
3. ### Relativistic laws of motion and E = mc^2^

Professor Susskind begins with a review of space- and time-like intervals, and explains how these intervals relate to causality and action at a distance. He then introduces space-time four-vectors and four-velocity in particular. After presenting... [more]
4. ### Classical field theory

Professor Susskind moves on from relativity to introduce classical field theory. The most commonly studied classical field is the electromagnetic field; however, we will start with a less complex field - one in which the field values only depends on... [more]
5. ### Particles and fields

Professor Susskind begins with a discussion of how, in the case of charged particle in an electromagnetic field, the particle affects the field and vice-versa. This effect arises from cross terms in the Lagrangian. He then derives the action,... [more]
6. ### The Lorentz force law

After a review of Einstein & Minkowski notation and an introduction to tensors, Professor Susskind derives the relativistic Lorentz force law from the Lagrangian for a particle in a vector field. At the end of the lecture, he introduces the the... [more]
7. ### The fundamental principles of physical laws

Professor Susskind elaborates on the four fundamental principles that apply to all physical laws. He then reviews the derivation of the Lorentz force law as an example of the application of these principles. The lecture closes with an introduction... [more]
8. ### Maxwell's equations

After a brief review of gauge invariance, Professor Susskind describes the introductory paragraph of Einstein's 1905 paper "On the Electrodynamics of Moving Bodies," and derives the results of the paragraph in terms of the relativistic... [more]
9. ### Lagrangian for Maxwell's equations

Professor Susskind begins the lecture by solving Maxwell's equations for electromagnetic plane waves. He then uses the principles of action, locality and Lorentz invariance to develop the Lagrangian for electrodynamics for the special case without... [more]
10. ### Connection between classical mechanics and field theory

Professor Susskind begins the final lecture with a review and comparison of the three different concepts of momentum: mechanical momentum from Newtonian mechanics, canonical momentum from the Lagrangian formulation of mechanics, and momentum that is... [more]