There is quite a bit of experimental data obtained about the phenomenon that is referred to as a single electron. But all this data is mathematical. Problem lies in interpreting this data with proper reality.
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Particle or Wave
We are not even sure if the electron is a particle or a wave. On this determination depends the correct interpretation of the rest of data about electron. Mathematical numbers don’t mean much even if you give them the labels like spin, charge, etc., because none of these labels have been clearly defined.
The problem lies in the fact that “substance” is defined for matter only and not for the constituents of the atom of matter. The substance of atom is thought of as having a constant density. It is supposed that there is no substance if it doesn’t meet certain arbitrary criterion of density as “matter”.
The fact of the matter is that the substance can have decreasing density without limit. Substance starts out as atomic matter; but it acts more like a non-atomic fluid inside the atom as its density decreases. This is the case with the electronic substance.
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Particle is the Substance
An electron is not rigid and structured like the nucleus. The substance density of electron is 1840th of the proton or the neutron. The electron as a “particle” is moving very fast and its center of mass cannot be determined. Since there is no center of mass to differntiate electrons as particles, all electrons form a fluid-like continuum that is flowing extremely fast.

A very fast flowing fluid acquires wave-like characteristics. This answers the wave-particle question about the electron. An electron is a particle because it has substance. It does not necessarily exist as a discrete (single) particle in space.
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Energy is the Waving Substance
All interactions in chemistry or in quantum mechanics have precise energy values. This discreteness of energy values does not mean that substances involved are discrete particles in space. Therefore, a continuum of electronic fluid can have discrete energy values of interactions.
Discrete value of interaction is what Einstein called “energy particle”. This doesn’t mean that electrons and photons are discrete entities in space. Both electrons and photons form a continuum of substance as a non-atomic fluid, yet they have discrete energy values of interaction.
This wave-particle confusion has been the greatest inconsistency in the science of physics. It arises because of the substance-energy confusion as outlined above. Unfortumately, this confusion entered the science through Einstein’s 1905 paper on Liqht Quanta, where he said,
“According to the assumption considered here, when a light ray starting from a point is propagated, the energy is not continuously distributed over an ever increasing volume, but it consists of a finite number of energy quanta, localised in space, which move without being divided and which can be absorbed or emitted only as a whole.”
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Einstein’s Real Discovery
The most important discovery of Einstein is that light is not a motion in some arbitrarily considered stationary aether; instead light is a substance that is moving at an extremely rapid rate. It is this extreme rapid movement, which imparts wave characteristics to light and electrons.
Light is an extremely fast moving waving substance.
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