Where Is the Center of the Universe? Stop Looking — It’s Everywhere and Nowhere at Once

Key Takeaways on the Center of the Universe

• Where is the center of the universe? In 1929, Edwin Hubble concluded that there isn’t one, as space continues to expand.
• Gravity can create a “center,” but because gravity pulls equally on all objects across the universe, galaxies, planets, and stars are distributed evenly.
• The center of the universe can be nowhere and everywhere all at once because the universe looks the same from every perspective. No matter where you are in the universe, the rest of space is moving away from you, suggesting that at one point, you were at the center of the universe.

Whatever you may have heard, the center of the universe isn’t located in Times Square, or a French railway station, or the town of Wallace, Idaho. But that’s not a dig at the cosmic relevance of anyone’s most cherished coordinates — the center of the universe isn’t located anywhere else, either.

It seems impossible. We know the universe began with a Big Bang 13.8 billion years ago and has been expanding ever since, according to NASA. So there must be a place, somewhere at the heart of all existence, where it began: a center. But this is a misunderstanding.

Though we tend to picture the Big Bang as a classic explosion — starting from a single point, like a hand grenade, then rushing outward in spherical form — it was utterly unlike any familiar examples we’re tempted to cite. It was an explosion of space, not an explosion in space; the usual rules don’t apply.

Janna Levin, a cosmologist at Barnard College of Columbia University, suggests that we think of the universe instead as a soap bubble. Importantly, unlike real-life bubbles, this one has no interior or exterior — forget everything but the surface, and consider that you could wander this sudsy realm for eternity without finding a privileged position.

“Everywhere I go on the soap bubble looks like every other place,” Levin says. “No point lays claim to the center.”

Read More: The Universe Started as a “Hot Soup of Particles and Photons” 13.8 Billion Years Ago

Where Is the Center of the Universe?

The first hint of this bizarre conclusion came in 1929, when the American astronomer Edwin Hubble discovered that every single galaxy beyond ours is speeding away from Earth, and that those farthest away are receding fastest, according to an article published in Astronomy. At first glance, this might seem to suggest that, by some extraordinary coincidence, our humble planet is in fact poised at the center of the universe.

But there’s another explanation, one better supported by observational data and the predictions of relativity theory: the universe looks the same from every perspective, because spacetime itself is expanding uniformly everywhere, according to Britannica. That means there is nothing special about our vantage point; alien astronomers a billion light-years away would see the Milky Way and all other galaxies receding from theirs.

This is exactly how things work on the soap bubble. Imagine its surface covered with dots, representing galaxies — as the bubble grows, the dots spread farther apart as the space between them stretches. The universe is, of course, three-dimensional, rather than two-dimensional like the bubble’s surface. Yet it behaves in the same way, expanding everywhere at every moment, with nothing you could call a center.

Gravity Makes Centers — Why Not Here?

You may have another nagging intuition, based on the more easily comprehended principles of classical physics. Four centuries ago, Isaac Newton demonstrated why the Earth is round, why planets orbit stars, and why solar systems orbit galaxies —in a word, gravity. Every other unit of astronomy has a gravitational hub toward which all nearby matter is drawn, giving us our cosmic notion of centrality. Why doesn’t the universe?

Each galaxy does indeed exert gravitational force on all the others, but no one galaxy triumphs in this titanic tug-of-war. The pull is equal in every direction. As a result, the universe stays remarkably smooth at the largest scale, with matter distributed more or less evenly throughout. This uniformity leads to a different outcome than we see at the levels of planets, solar systems, and galaxies. “If I put that into Einstein’s equations,” Levin explains, “it says that there is no center.”

Rewinding The Universe

Now, let’s relax our prohibition on the soap bubble’s interior. If we reframe that interior not as space but as time, we can play the inflation process back in reverse. As the bubble shrinks, we can watch the intervening space diminish and the dots draw closer until every point converges. This is the beginning, the instant just before the Big Bang. There, you might say, we have a center — it’s destined to disappear as soon as expansion begins, but for the moment it exists, and it contains the entire universe.

So, back to the question. Where is the center of the universe? It turns out there are two meaningful answers: nowhere and everywhere at once. That is, no one point is exceptional now, but every point once was. Back in the cosmogonic embryo, all that exists today — Times Square, Idaho, your living room — was part and parcel of the absolute. In some sense, it still is.

Read More: Did Our Universe Eat Baby Universes, Triggering Dark Energy?

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