"The greatest puzzle in modern physics." -Int’l Med. & Surg. Survey

In 1921 Nobel Prize winning physicist Sir William Henry Bragg published the short pamphlet "Electrons and Ether Waves." This paper is concerned with one of the outstanding problems in physics, the connection between ether waves and electrons and the relation between the wave length of the ether radiations and the velocity of the ejected electrons. The lecture gives a non-mathematical account of information on the matter.

The essential feature of the information given is the interchangeability of ether waves and electrons. Energy can be transferred from one to another through the agency of matter. The transference is governed by the simplest arithmetical rules. In the exchange it is the frequency of the wave which is to be set against the energy of the electron, and this constitutes the greatest puzzle in modern physics. It is the block at one point which is choking the entire traffic, and on which, therefore, all interests should concentrate.

According to ancient and medieval science, aether, also spelled æther or ether and also called quintessence, is the material that fills the region of the universe above the terrestrial sphere. The concept of aether was used in several theories to explain several natural phenomena, such as the traveling of light and gravity. In the late 19th century, physicists postulated that aether permeated all throughout space, providing a medium through which light could travel in a vacuum.

Sir William Henry Bragg (1862 – 1942) was a British physicist, chemist, mathematician and active sportsman who uniquely shared a Nobel Prize with his son William Lawrence Bragg – the 1915 Nobel Prize in Physics: "for their services in the analysis of crystal structure by means of X-rays". The mineral Braggite is named after him and his son. He was knighted in 1920.

Other books by Bragg include:

The World of Sound (1920)

The Crystalline State – The Romanes Lecture for 1925. Oxford, 1925.

Concerning the Nature of Things (1925)

Old Trades and New Knowledge (1926)

An Introduction to Crystal Analysis (1928)

The Universe of Light (1933)