Luminiferous aether

[[File:Aethercollector.jpg|thumb|165px|An old æther-collecting gadget(or perhaps a new steampunk one).]]{{needs sources}}
{{hatnote|For other uses of the term ether (and aether), see the fork page [[ether]].}}

'''Ether''', or æther, was 
the stuff used to replenish mana/MP
 
Ike’s signature skill in ''Fire Emblem''
 
the lifeblood of the Bionis
 an invisible substance that was theorized to fill all the problem parts in pre-Einsteinian [[physics]] theories. In its final incarnation, people invoked it to fill outer space and explain how [[light]] could travel with no medium to carry it.

==A history of ether==
Aether has its origins in mythology. Aether was thought to be the pure essence that the gods breathe, similar to the air that the mortals breathe, and it was also personified as a primordial god 
uncreatively
 called Aether, the son of Erebus (darkness) and Nyx (night).

In physics, aether also had a long and respected history. It generally played the role of That Thing Which [[Magic]]ally Solves All the Problems in My Pet Theory, a part currently enjoyed by [[dark energy]].

The idea of an aether-like substance in physics has been around since 4th century BC. [[Plato]], mentioned a "most translucent kind which is called by the name of aether" when talking about air in Timaeus 58d, but didn't touch on it further. [[Aristotle]], who was taught by Plato, wrote an essay in Physics Book IV, section 8 that eventually got summarized over the years as the statement: "Nature abhors a vacuum". This concept led him, and many other philosophers, to speculate that all the space in the world must be filled with something, even when it didn't appear to be. That thing was, of course, aether, or "quintessence" - more about that later. He described it as an element which is lighter than air and is located above it, whereas air is lighter than water, and water is lighter than earth. In his book On the Heavens, he expanded on the subject, where ether is the new "first" element - later turning into the fifth element - to the system of the classical elements, and is located in the celestial regions and heavenly bodies. Ether moved circularly, with no contrary (unnatural) motion, and had none of the qualities the other elements had, having no temperature or wetness. Along with making up outer space, the Sun, Moon, and planets were also each embedded within its crystalline sphere of hard ether.

Quintessence is the Latinate fifth element, and was thought to be a medium similar or identical to ether. Quintessence was part of the medieval alchemists' elemental system, which consisted of the four classical elements, in addition to sulphur/sulfur, which characterized the principle of combustibility; mercury, which contained the idealized principle of metallic properties; and, of course, quintessence, which made up the heavenly bodies.

Since mechanical waves need a medium, people thought electromagnetic radiation also needs a medium (the aether). Originally, aether was believed to be a gas or a liquid, similar to caloric.

When Malus discovered polarization, wave theory proponents like Young and Fresnel assumed the light was a transverse wave. Such waves can propagate only in solids.

The idea was upheld in the late nineteenth century when the [[Michelson-Morley experiment]] 
disproved its existence
 put it in big trouble. The idea of aether had its apologists as late as in the 1920s, when the most advanced Lorentz aether theory finally got disproved. Some defenders of the aether, i.e. Dayton C. Miller and Herbert E. Ives, conducted their experiments and held to their beliefs as late as the 1930s.

==See also==
*[[Michelson-Morley experiment]]
*[[Relativity]]
*[[Zero-point energy]]
*[[Anti-relativity]]

[[Category:Magic]]
[[Category:Physics]]

Categories: Magic, Physics