What do you mean the electron was never directly observed or measured? It is perhaps the single most accurately measured object in the world. We know all measurable properties of an electron to a much better degree of accuracy than, say, the size of a chair. We can predict with much much much more accuracy what will happen if you fire a beam of electrons at something than if you fire a tennis ball cannon.
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What do you mean the electron was never directly observed or measured? It is perhaps the single most accurately measured object in the world. We know all measurable properties of an electron to a much better degree of accuracy than, say, the size of a chair. We can predict with much much much more accuracy what will happen if you fire a beam of electrons at something than if you fire a tennis ball cannon.
It’s never been physically measured only indirectly that is to say it’s never been observed by any instrument physically.
It exists only by inference.