Lecture Description
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 time - not on any spatial dimensions.
Professor Susskind reviews the action principle and the Lagrangian formulation of classical mechanics, and describes how they apply to fields. He then shows how the generalized classical Lagrangian results in a wave equation much like a multi-dimensional harmonic oscillator.
Next, professor Susskind brings in relativity and demonstrates how to create a Lorentz invariant action, which implies that the Lagrangian must be a scalar.
The lecture concludes with a discussion of how a particle interacts with a scalar field, and how the scalar field can give rise to a mass for an otherwise massless particle. This is the Higgs mass mechanism, and the simple time dependent field we started the lecture with is the Higgs field.
Course Index
- The Lorentz Transform
- Adding Velocities
- Relativistic Laws of Motion and E = mc2
- Classical Field Theory
- Particles and Fields
- The Lorentz Force Law
- The Fundamental Principles of Physical Laws
- Maxwell's Equations
- Lagrangian for Maxwell's Equations
- Connection Between Classical Mechanics and Field Theory
Course Description
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.