Relativistic Charged Particle in An Electromagnetic Field
The Lagrangian for a relativistic charged particle is given by:
Thus the particle's canonical (total) momentum is
that is, the sum of the kinetic momentum and the potential momentum.
Solving for the velocity, we get
So the Hamiltonian is
From this we get the force equation (equivalent to the Euler–Lagrange equation)
from which one can derive
An equivalent expression for the Hamiltonian as function of the relativistic (kinetic) momentum, is
This has the advantage that can be measured experimentally whereas cannot. Notice that the Hamiltonian (total energy) can be viewed as the sum of the relativistic energy (kinetic+rest), plus the potential energy,
Read more about this topic: Hamiltonian Mechanics
Famous quotes containing the words charged, particle and/or field:
“The last alternatives they face
Of face, without the life to save,
Being from all salvation weaned
A stag charged both at heel and head:
Who would come back is turned a fiend
Instructed by the fiery dead.”
—Allen Tate (18991979)
“The way to learn German, is, to read the same dozen pages over and over a hundred times, till you know every word and particle in them, and can pronounce and repeat them by heart.”
—Ralph Waldo Emerson (18031882)
“You cannot go into any field or wood, but it will seem as if every stone had been turned, and the bark on every tree ripped up. But, after all, it is much easier to discover than to see when the cover is off. It has been well said that the attitude of inspection is prone. Wisdom does not inspect, but behold.”
—Henry David Thoreau (18171862)