The Center Cannot Hold

Tap dancing with cosmology. Essay. 1100 words, 6-minute read.

Image: https://bigthink.com/starts-with-a-bang/logarithmic-view-universe/

The Center Cannot Hold

By Ray Tabler

Galileo Galilei was a pioneering, renaissance astronomer. But he is most famous for being dragged before the inquisition for daring to state that the Earth orbited about the Sun. Trouble was that the Catholic Church’s doctrine claimed otherwise. If you think fighting city hall is tough, try going 10 rounds with the Holy See.

Galileo was convicted of heresy, and sentenced to house arrest for the rest of his life. His written works on the subject of heliocentrism (the theory that the sun is at the center of the solar system) were banned for over a hundred years. Now, Galileo’s persecutors weren’t knuckle-dragging louts or dogmatic fanatics. Most of them weren’t anyway. But Galileo messed around and challenged the authority of the church (without really intending to, granted). And authority has a thing about being challenged. He had to be made an example of. And he was. Of course, that example today stands as a martyr of science. The story I read relates that after being shown the tray of nasty implements the inquisition employed to obtain confessions and recantations, Galileo decided to play along. He stated for the court that the Earth does not move. Then he whispered, “but it does move.”

It took a few hundred years and long string of Popes, but the Church eventually admitted that Galileo was right after all, and reversed the judgement. So, all is, more or less, forgiven. 🙄

The irony in this tale is that the center of the universe has shifted about quite a bit since the days Galileo squinted through a telescope at the moons of Jupiter. Common wisdom then had it that the Earth stood at the middle, with the stars, planets, and other heavenly bodies dancing a complicated minuet all around. It was confusing, and only astrologers could keep track of which tiny dot in the sky was which, and where they’d all be on any given date in the past or the future. There was a good living to be made off of identifying auspicious days to be born, get married, start a war, or what have you. Then that pesky Copernicus came along and ruined everything.

After a few more excommunications, and a lot of vicious argument, the consensus shifted, and the center of the universe snapped to the Sun. Our sun. The math was simpler, and only astrologers were unhappy. Although they are still around, and making a living off of identifying auspicious days to be born, get married, start a war, or what have you. Go figure.

Like many scientific pursuits, astronomy is limited by the instruments employed, telescopes. The bigger and better your telescope, the farther and better you can see. And, as that visionary philosopher Yogi Berra decreed, “You can see a lot by just lookin’.” The evidence observed told us that our Sun is not unique. Our solar system is just a nondescript clutch of spinning bodies, amid billions of other stars. Our sun lost its coveted position as the center of all things.

With bigger and better scopes, it eventually became undeniable that the small, fuzzy patches of light in the sky are actually other galaxies, separate and startingly distant from our own Milky Way. Not only is our galaxy not at the middle, it’s not even the largest galaxy around. Andromeda is twice as big. But we consoled ourselves that size doesn’t matter.

Astronomer Edwin Hubble discovered that all other galaxies appear to be flying away from the Milky Way. And, for a brief, heady moment, we thrilled at the idea that maybe we were special after all. Then, the realization hit like a bucket of cold water. Every galaxy is flying away from every other galaxy. The universe is expanding at break-neck speed, a lingering aftereffect from the big bang which started it all.

An amusing digression: One of the Ignobel Prize award ceremonies featured an opera about the big bang entitled, “Il Kaboom Grosso.” If you have a link to the performance of this masterwork, for the love of humanity, please please please share it. 🙏 I searched, but believe Big Science has suppressed knowledge of its existence.

Demoted yet again, we seemed to be farther away from the center of the universe than ever before. 😒

Still, how do you define “universe?” And I’m not talking about that multiverse thing. That’s a whole other essay. You see, our universe is expanding so fast that at some distance, it’s zooming away at faster than the speed of light, relative to us. Which means the light from beyond the edge of that spherical volume will never reach Earth. It’s just too slow to catch up to us. That is beyond the “observable universe.” And, as far as we’re concerned, it just doesn’t exist.

As our telescopes get better and better, astronomers might catch a glimpse of that fabled barrier, billions and billions of light-years away. What’s beyond it? I have no idea. Maybe it’s turtles all the way down.

Image: https://johnmjennings.com/turtles-all-the-way-down/

But, wait! If we sit at the middle of an unimaginably immense sphere, defined by the relativistic velocity of the rest of the universe fleeing from us as if we’re a cosmic bad smell, then are we not, by definition, the center of the observable universe? What an Earth-shaking thought. And it’s not just our galaxy at the center. Our solar system is located smack dab in the middle of the observable universe. Since we stand upon the Earth, viewing the observable universe from its surface, the Earth is at the center.

In fact, you, personally, are at the center of your very own observable universe. Just as I am at the center of my own personal observable universe. If we are separated by 5 feet or 1000 miles, the edge of your visible universe extends 5 feet or 1000 miles beyond mine in your direction, and mine extends 5 feet or 1000 miles the other way beyond yours. Light from the edge of your observable universe will never reach me, and arguably doesn’t exist (from my perspective). In a very real sense, our universes overlap, but don’t coincide. Unless I stand up and travel the 5 feet, or 1000 miles, to where you are. Unravel that Gordian knot. 🪢

The more things change, the more they remain the same. The center of the universe zoomed away from us, only to return like a whistling, cosmic boomerang. Seriously though, this argument tiptoes the ragged edge between science and sophistry. The center of the universe, whatever that means, has not shifted a Planck length the whole time. Only our understanding has drifted with the tide of scientific inquiry and debate. And, honestly, I don’t see that changing anytime soon.

END.