Peoples' ideas of the center of the Universe have undergone several relocations throughout history. Most have been little more than window dressing for individuals trying to to place themselves at the center of the Universe.
For centuries, various groups of people believed the land they lived in was the center of the universe. For example, the Ancient Greeks had their Omphalos, ("navel-stone") at Delphi, and the Chinese had their Middle Kingdom with, I believe an analogous stone. Uisnach in Ireland, Cuzco (literally "Navel of the world") in Peru and Mount Agung in Bali are also similarly centrally located.
Then came people like Aristotle1 and later Ptolemy who placed the Earth at the center of the universe.
In the regression of the Christian Era, giving us a flat Earth once again, some people placed Jerusalem at the center.
Then, Nicolaus Copernicus theorized that the Earth revolved around the Sun, placing it at the center. After many burnings at the stake in a vain attempt to suppress the idea, this became the accepted view.
Accepted, that is, until Isaac Newton's mechanics and the realization that some stars are much larger than the Sun dislodged our nearest star from its exalted position. Some placed the center at the center of the Milky Way galaxy, the only one known to exist at the time. But generally, there were two views:
- There is no center.
- There is a motionless fluid, known as the Ether, whch permeates space. This was later generalized to a preferred "motionless" frame of reference.
The Michelson-Morley Experiment
did away with the ether.
Then along came general relativity with a prediction of an expanding universe and Edwin Hubble with his observational proof.
Every point in the universe is racing away from every other; not only that, at the moment of the Big Bang, every point started racing away from every other point.
This led many people (including Stephen Hawking) to the conclusion that every point is at the center of the Universe.
Um. Remember what I said at the beginning of this writeup? Do you know that annoying person2 who imagines that the universe revolves around them?
I'm afraid they're right.
1An old windbag according to Petr Beckmann but it was still a change.
2Zaphod Beeblebrox actually had this demonstrated to him in The Restaurant at the End of the Universe.