In ages past, and in the not so distant past, people held Earth as the unchallenged center of the universe. How foolish! Modern people hold that it is not. Earth flies about the Sun. The Sun in turn, among numberless other stars situated toward the edge of the Milky Way, flies around the center of the galaxy. That galaxy is itself but one of a countless horde of other galaxies all flying hither and yon, mostly yon. We live in an increasingly expanding universe.
Here we were in a class called analytical geometry, excitement unbound. Grids, curves, lines, numbers, letters, and mostly, lots of math equations remained the order of the day. Our instructor presented the famous graph grid consisting of two lines perpendicular to each other, the x line going left and right, and the y line going up and down, toward four different infinities right there on the chalk board. The Cartesian coordinate system, he called it.
Anyway, the lines crossed each other in the middle, their cross hairs aimed right where the Big Zero was. The Origin. On the grid, but well off center, was a noticeable dot, its location described by some proper x and y values. Not Zero. Not the origin.
Holding us with bated breath, the instructor discussed passionately that as you do certain mathematical calculations, you can shift the x and y cross hairs so that they move right over the off-center dot, all the while keeping careful notice where the old crossing used to be, and where everything else was, too. The Big Zero changed place! By such marvelous manipulation, a purportedly useful, new Origin of the whole system took place. The same kind of thing could be done in three dimensional notation, apparently. Or in any number of dimensions for that matter.
In an infinite system, that is, in the kind that math people like to think about, any place can be the center of the system. Pick any origin and you can describe anywhere else in terms of that center. Pick another, and you can still keep track of everywhere just as easily. So, the "center" can be be any place you want it to be in that infinite world ...
Huh ...
Well ...
Oh ...
But, wait! What if the system were not merely in the mathematical chalk board mind, but were the world "out there," the real universe? (Revelation dawns way late.)
Now, they tell us there is no "edge" to the real universe. All things holding equal (which never they do, of course), if you start outbound from here in one lightning push as fast and furious for as far as you can, you just go from here to there (and back to here) traveling the universe in a (straight!) cosmic loop, never approaching an edge. I confess not to get it, but that's the way it works. They say. Not that anybody's ever gone and done it.
So, here's the deal: In an unimaginably huge space-time universe such as ours, Earth might as well be the center of that universe as anywhere else. Math models just don't care what arbitrary points are chosen as their respective origins. Everywhere else can be described in terms of some referred starting point. Indeed, people who study these things tell us that anywhere you may stand in the real universe, if you look out very carefully in any direction into the skies, you will notice that the mass of galaxies is moving away from you at an increasingly great rate of speed. You are the center away from which that mass exodus takes place, no matter whence you gaze into the cosmos!
Those old fools through the past archaic centuries who stupidly thought Earth was the center of the universe ...
Well, now, they were righter than moderns who said it wasn't.
