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Problems with the idea of Electron Spin



Keywords


electron, spin, electron spin, intrinsic spin, angular momentum, magnetic moment

Rotation of a charge


The ideas of electron spin and angular momentum started with the Bohr model of the atom. However, as quantum theory developed, the idea emerged that the electron possessed these properties of its own right rather than as a consequence of its orbital motion. Thus the electron is said to posses an intrinsic spin which gives it both angular momentum and a magnetic moment. The primary evidence for this is the Stern-Gerlach experiment. These concepts do not fit the Pure Charge Theory which I have developed.

A pure charge is a perfect sphere of charge. It consists of both the surface and the electric field which surrounds the charge. Indeed, the surface of the charge is but the raw edge of the electric polarisation of space which is the electric field of the charge. Movement of the charge relative to the background presence of the polarisation fields of the other charges in the universe generates a magnetic field surrounding the charge given by the equation

If we use this equation for the magnetic field surrounding a single charge and sum over all the charges which constitute an electric current in a wire, we get the well known equation

Now the electric field of a single charge is

from which we can obtain an expression for
Now substituting gives
From which we conclude that we can account for the magnetic field produced by a current in an electric circuit by assuming that the movement of the electric fields of the individual electrons generates the magnetic field.

If we now imagine a single charge at rest relative to the background presence of the polarisation fields of the other charges in the universe, but rotating with an angular velocity , then and the magnetic field surrounding the charge should be

and we can substitute for giving
The vector may be separated into the product of its magnitude and direction and the r cancels giving
Such a magnetic field is unable to exist for two very good reasons. It would have an infinite energy content and its divergence is everywhere non zero. We therefore conclude that either magnetic fields are not generated by the movement of electric fields or that rotation of the electric field of a charge is meaningless.

We can see how an electron orbiting the nucleus of an atom is like an electric current flowing around a loop of wire. Logic tell us that we can split the the surface of a revolving charge into a number of circular strips which should act as electric currents flowing in wire loops. This is false logic. It is false logic because it omits the fact that electric charge is discrete in nature. The electric current flowing in the wire consists of the movement of vast number of electrons each with its own electric field extending into the surrounding universe. A single electron cannot be split up into millions of sub-units, so a circular strip of the surface of the electron cannot behave like a current carrying wire loop.

The same logic applies to angular momentum. We have found that a charge possesses the property of inertia. When we say that a car has momentum we read it as "mass times velocity", but what do we mean by mass. We mean the ability of the car to resist acceleration, in other words we are referring to its inertia. The car has momentum because all of its quarks and electrons will resist being decelerated and when the car impacts with another car, this will generate a force which will accelerate the other car. If the cars do not hit head on, they will spin and we can now say that our car has angular momentum! The car does not possess angular momentum because its quarks and electrons are set spinning, it possesses angular momentum because the velocities of its quarks and electrons have been modified so that the car as a whole is rotating. The angular momentum is property of the relative movement of the atoms of the car with regard to one another. If we have just one electron orbiting a proton, it has something to go round and we can see this form of relative motion which we call orbiting, but if the electron is alone, it has nothing with which to have relative motion about. It has an inertial property, but that is associated with movement which generates a surrounding magnetic field. The inertial property of a charge is a property of the whole charge, not of arbitrary elements of its surface. Such elements might well be imagined to be rotating but they have no inertial properties and so the charge cannot possesses any angular momnetum.

There is also a problem with the forces which act between small magnetic dipoles. The force between them is inversely proportional to to the forth power of the distance between them. If we try to model the motion of two objects obeying such a force law, we find that they are unable to orbit about each other in the same way that planets can orbit the sun. Either they will pass each other by, or they will collide. There are no in betweens. Electrons in chaotic motion within an atom would on occasions come close enough to each other for the attraction between their magnetic moments to overcome both their velocity and the electric repulsion between them and they would stick together. They clearly do not do this casting another doubt on the idea of the intrinsic spin of the electron.


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© Copyright Bruce Harvey 1997.