N. Anderson

Helicity and variational principles for Maxwell's equations

The connection is established between helicity and the action associated with recent canonical variational principles for the equations of the electromagnetic field.

A variational principle for Maxwell's equations

Using a canonical approach, we present a direct variational formulation for the equations of the electromagnetic field in terms of the field vectors.

Complementary variational principles for Maxwell's equations II

New complementary variational principles for Maxwells equations are derived from a canonical formulation in which potentials and field vectors constitute the conjugate variables.

The formation of a plasma sheath with secondary electron emission

Abstract A simple model is constructed for the formation of a plasma sheath which takes into account in a simple way the emission of secondary electrons from the surface of the wall bounding the plasma.

Variational principles for Maxwell's equations II

New variational principles for the electromagnetic field arc derived in terms of the field vectors within a canonical framework.

Bounds for the resistance of a conductor of a given form

New upper and lower bounds for the resistance of a. conductor of given form are derived in a unified manner from the canonical theory of complementary extremum principles.

Duality transformation and invariants of the electromagnetic field

The structure of Maxwells equations under duality transformation and its connection with the work of Heaviside (1885) are discussed. A scheme for generating the associated invariants is also presented.

An extension of a conservation law for the electromagnetic field

A conservation law for current-free electromagnetic fields derived by Lipkin is extended to include certain types of current distribution.

The formation of a plasma sheath

Abstract In this paper we consider how the electric potential varies in space and time during the formation of a plasma sheath. We give the variation of the wall potential in time, the potential profile at various stages of the sheath formation and the variation of the total current at the wall.

A Theoretical Analysis of the Retarding Potential Difference Technique

In this paper we provide a theoretical explanation of some of the phenomena which can arise in experiments using the retarding potential difference (R.P.D.) technique. In particular we can account for the occurrence of negative and of non-linear signals, and possibly also for the appearance of spurious peaks.