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According to ancient and medieval science, aether (Greek αἰθήρ aithēr[1]), also spelled æther or ether, is the material that fills the region of the Universe above the terrestrial sphere.
[edit] Mythological origins
The word αἰθήρ (aithēr) in Homeric Greek means "pure, fresh air" or "clear sky", imagined in Greek mythology to be the pure essence where the gods lived and which they breathed, analogous to the air breathed by mortals (also personified as a deity, Aether, the son of Erebus and Nyx). It corresponds to the concept of akasha in Hindu philosophy and is linked to Brihaspati (or the planet Jupiter) and the center direction of the compass. It is related to αἴθω "to incinerate"[2], also intransitive "to burn, to shine" (related is the name Aithiopes (Ethiopians)), meaning "people with a burnt (black) visage". See also Empyrean.
[edit] Fifth element
Plato's Timaeus posits the existence of a fifth element (corresponding to the fifth remaining Platonic solid, the dodecahedron) called quintessence, of which the cosmos and all celestial bodies are made.
Aristotle included aether in the system of the classical elements of Ionic philosophy as the "fifth element" (the quintessence), on the principle that the four terrestrial elements were subject to change and moved naturally in straight lines while no change had been observed in the celestial regions and the heavenly bodies moved in circles. In Aristotle's system aether had no qualities (was neither hot, cold, wet, or dry), was incapable of change (with the exception of change of place), and by its nature moved in circles.[3] Medieval scholastic philosophers granted aether changes of density, in which the bodies of the planets were considered to be denser than the medium which filled the rest of the universe.[4] Robert Fludd stated that the aether was of the character that it was "subtler than light". Fludd cites the 3rd century view of Plotinus, concerning the aether as penetrative and non-material.[5]
In the series Vampire Academy by Richelle Mead, Aether is mentioned as Spirit, and is a rare aspect.
[edit] Legacy
The concept of the aether impacted science long after scientists had rejected the ancient theory of the five elements. Prior to fully modern theories of electromagnetism, many scientists applied the term "luminiferous aether" to the pervasive medium through which they thought light must propagate. The modern understanding of electromagnetism, including Einstein's particle theory of light and various scientific experiments of general relativity, has removed the need for a substance like aether to fill the otherwise empty parts of the universe. Newton's and Maxwell's aether model (the latter being a "classic static aether") were both developed from this classical element. However, the null result of the Michelson-Morley experiment in 1887 led to the decline of the aether model. Albert Einstein, in an interpretation he offered for his theory of special relativity, dismissed it, as per Occam's razor. He later reinstated a logical need for an aether in a commentary on his theory of general relativity ("according to the general theory of relativity space without ether is unthinkable").
[edit] References
- General
- Specific
- ^ "ether". The American Heritage Dictionary of the English Language. 4th ed. Boston: Houghton Mifflin, 2006.
- ^ Pokorny, Julius (1959). Indogermanisches etymologisches Wörterbuch, s.v. ai-dh-.
- ^ G. E. R. Lloyd, Aristotle: The Growth and Structure of his Thought, Cambridge: Cambridge Univ. Pr., 1968, pp. 133-139, ISBN 0-521-09456-9.
- ^ E. Grant, Planets, Stars, & Orbs: The Medieval Cosmos, 1200-1687, Cambridge: Cambridge Univ. Pr., 1994, pp. 422-428, ISBN 0-521-56509-X.
- ^ Robert Fludd, "Mosaical Philosophy". London, Humphrey Moseley, 1659. Pg 221.
