"The most incomprehnsible thing about the universe is that it is comprehensible"- Albert Einstein
To my faithful blog followers- I apologize for my leave of absence. A grueling summer filled with too much fun, a trip to Canada's Atlantic provinces, and a medical school application later...I am back.
Aristotle imagined a universe where there existed a 'luminiferous ether', or just 'ether' for short (1). The term is of course spelled with the Latin dipthong "ash" replacing the first letter 'e' (Æther), but I will use the modern English spelling as my keyboard does not contain Latin characters :)
This ether, considered a 'classical element', refers to the material which fills all of the universe outside of the terrestrial sphere. This material was believed to be the 'messenger' of all forces in the universe - basically, imagine a continuous series of invisible tubes connecting each and every object, like a GMAT permutation question gone mad. When an object moves, it pushes on the ether, which pushes on another object. This is how the universe was thought to operate. Of course, with no good scientific method to prove this concept right or wrong, it remained a prominent, though rarely discussed, idea for quite some time
Countless experiments were carried out in search of a method to study the ether, as well as to prove its' very existence. James Clerk Maxwell carried out one such experiment near the late 1860's- altogether, a fairly well thought-out study. He proposed that: if the Earth moves through the ether, and since the Earth moves in different directions at different parts of the year, then the speed of light must vary, even if only slightly, at different times of the year. This experiment is a good example of those which attempt to either study, or prove the existence of, the ether, because it very clearly outlines the dominant assumption in these experiments: there can be an absolute observation of physical laws, due to the absolute nature of ether- in essence, the ether is the absolute reference with which to compare an observation.
We now know that there is no 'ether'. There is not a mysterious, immeasurable material filling the voids of space with which matter does not reside. This concept of an ether died with the assumption that the laws of physics, including the speed of light, will remain constant with uniformly moving observers- an assumption made by Einstein in his theory of special relativity, where he showed that observations are dependent upon the observer. By assuming that the speed of light is the same in all frames of reference, there will be variation in time- in other words, time is not absolute. This notion, combined with Maxwell's theories of electricity and magnetism, dictates that time cannot be considered separate from the three physical dimensions; otherwise known as the concept of 'space-time'.
Space-time is not flat- it is curved and distorted by the masses and energies within it. In a hypothetical universe without mass or energy (hypothetical, because without mass and energy it could not possibly be observed) there would be no 'time' component of space-time; it would simply be a three-dimensional flat space.
Objects move within space-time, and bend and warp the fabric like a bowling ball on a mattress. It is the essence that 'fills' the universe...
I ask, given the scientific capabilities of his day, the limitations of previous discoveries, and lack of what we would today call the 'scientific method'...I ask, was Aristotle really all that wrong?
It has been said that Aristotle discovered and/or explained everything, and that everything since then is just a footnote...
1) Stephen Hawking & Leonard Mlodinow. The Grand Design. 2010. Random House Inc, New York, New York, United States.