Historically, the center of the universe has long been at the center of the earth. On the one hand, of course, this happened because people did not know what exactly the Universe is. In ancient times, the Earth for people was practically the entire universe. Around the Earth, according to the ancients, there were several celestial spheres. On these spheres were planets, and on the outermost side there was a shell with stars.
That is, the Universe, according to our ancestors, was the Earth with a small amount of “attachments” around it.
There were philosophical and scientific reasons to consider the Earth as the center of everything. In those ancient times, little was known about the structure of matter and about how the fundamental forces of nature work. There were no measuring instruments, microscopes, particle accelerators, and the like that could be used to find out anything about the world around us.
Therefore, people had no choice but to put forward more or less logical-sounding hypotheses. One such hypothesis goes back to Aristotle. It was he who conditionally divided matter into four classical elements: fire, water, earth and air. According to the philosopher, everything in this world should consist of these basic forms of matter and each of these types of matter must have a very specific type of motion.
Anything that contains a lot of air rises. Because the “natural place” of air is the sky. And everything always wants to return to its natural place. That is why smoke rises and does not remain on the Earth, Aristotle believed. The natural location of the earth element is the center of the universe. That’s why our planet wants to go there all the time. If we see something fall to the ground, it happens because the center of the universe is under our feet and this is logically, the center of the earth.
New knowledge
Given the level of knowledge then available (or lack thereof) this sounds quite plausible. However, even in ancient times there were scientists who saw things quite differently as they assumed that there are other worlds like the Earth. But such assumptions only complicate the question of the center of the universe.
When the early modern period arrived, people began to understand a little more. Isaac Newton explained to the whole world why things do fall and he figured out how the gravitational force works. Johannes Kepler, found out that the Earth revolves around the Sun, and not vice versa by analyzing observational data. Thus, we can’t possibly be the center of everything.
But even after these discoveries, there were people who were convinced that the Sun is at the center of the universe mainly because for a long time no one knew what to do with all the other stars. Nobody realized how far they were.
German astronomer Friedrich Wilhelm Bessel was only able to measure the distance to the star 61 Cygnus using the parallax method only in 1838. From that moment it became clear: the Universe is very, very big. It is much larger than the Earth that the ancient Greeks imagined and that the Sun is not at all in the very center among all these stars.
There were (from the point of view of that time) interesting reasons for this. If you look at the sky, you can see stars everywhere. There is no direction in which the sky looks fundamentally different.
For example, if one half of the sky was filled with stars and the other half was completely empty, this would be a sign that we are somewhere on the edge of a star cluster. But we see stars everywhere, no matter which way you look. In principle, the starry sky looks more or less the same in all directions.
Many perceived this fact as just a sign that we are still in the center. But now their opponents will object – what about other galaxies? Right! However, let’s not forget that astronomers learned about the existence of such a thing as “other galaxies” only in the 20s of the last century! Before that, it was absolutely incomprehensible what the nebulae in the sky consist of. From unimaginably distant stars? Or are they really just cosmic gas clouds very close to us?
Is the Universe the Milky Way?
Even at the beginning of the 20th century, that is, just over 120 years ago, there was a lot of controversy about where the Sun is in the Milky Way and whether or not Milky Way was all that exists in the Universe! Arguments have been made that we are at the very center of the Milky Way and that there is nothing else outside of it. And so we are at the center of the universe but there were also arguments against this assertion.
This whole story was clarified only by observations made by the US astronomer Edwin Hubble and his colleagues. They showed that there are many other galaxies in space and that we are not at the center of the Milky Way at all. Additionally, the Milky Way itself is far from all that exists in space.
However, the question of where the center of the universe is located remained open.
Hubble was the first to realize that all other galaxies are moving away from us. The farther they are, the faster they do it. It was very similar that we are exactly at the point from which the “recession” of galaxies occurs. If you look far enough into the past, it turned out that all of them were once located where our Earth is now. So, is our planet still the center of the universe?
But let’s leave the history of astronomy alone as we will review a thick book with the knowledge that modern science has.
So, the expansion of the universe is real. Indeed, everything around in space flies away from us. Rather, they do not fly away, but move away from each other. If we were to make observations from any other point in the Universe, we would see exactly the same picture – all galaxies are moving away from the observer.
Sounds weird. But in fact, there is nothing complicated here.
To understand this, let’s first remember that the Big Bang happened 13.8 billion years ago. Since then, the universe has been constantly expanding. Because of this expansion, we see other galaxies moving away from us, not because we are the center of anything but simply because the space itself is expanding and we are participating in this “movement” with all other galaxies!
O, but there must be somewhere in the middle, you may ask? Where did the Big Bang happen? Where did all this movement begin?
Where is the center of the universe? Where did it all start?
Yes, this question sounds logical. However, in reality this is not the case. The mistake in thinking is that we actually imagine the Big Bang as an explosion. In the case of an explosion, indeed, as a rule, it occurs somewhere in a specific place.
In its process, everything moves away from this place. No matter where we are in the debris cloud from this explosion, we will be able to see how everything else is moving. Those parts of the material that were close to the center should move faster and distant debris should slow down faster. If we carefully measure all this, we can calculate exactly where the explosion occurred.
But the Universe did not actually explode in the classical sense of the word. The expansion of the universe is not the expansion of galaxies from some central point. It’s an extension of space itself! This means that we see galaxies moving away from us because the space between them and us is expanding. Galaxies are just like “pulling the cosmos behind them.”
The Big Bang was not an “explosion” that took place in space at a specific location. The Big Bang was the event when space first appeared. There was no explosion in space. This was the event of the emergence of the cosmos itself, when all points of space began to move away from each other. Or to put it another way: at the time of the Big Bang, all places were one place or with different wording; the Big Bang happened everywhere at the same time!
Since then, the universe has grown incredibly. We can say with confidence that today every point in the Universe is the point where the Big Bang occurred. Because every point used to be the point where it all started. It is very difficult, almost impossible to imagine.
CMB radiation
However, an inquisitive reader may ask – if the center of the Universe is everywhere, and if every point of the Universe is its center, then what about the cosmic background radiation? Does it come from somewhere? Photons are coming, so to speak and they endlessly fly.
The point here is this. Yes, indeed, when astronomers look at the sky through radio telescopes, they always see the same radiation at the same temperature. Regardless of which direction they are looking, this is cosmic background (relic) radiation. And it came about about 400,000 years after the Big Bang, when the universe expanded and cooled enough for the energy it contained in the form of light to no longer be blocked by heavy particles.
It was then able to spread freely. But why is the cosmic microwave background still being detected? After all, all its photons should have already flown somewhere during this time?
The point here is this. When we look into the sky, we see exactly that part of this radiation that reaches our eyes right now, based on all the points of space that are most distant from us now. If we lived somewhere else in the Universe, we would see the same background. However, radiation would be coming from other points in space, those that are convenient for this place. There is no such unique place where cosmic background radiation would arise. It appeared everywhere at the same time, even where we are now. And it is precisely its presence that suggests that the Big Bang theory is correct.
The center of the universe does not exist or each of its points is the center.
“An extraordinary explosion that flared up in the void, as if fireworks – marked the beginning of the greatest holiday, illuminating the space where we first saw each other in the light of falling stars. Everything seemed so beautiful that it was impossible to look away from this grandiose light show – a show arranged by unknown forces that lie beyond all conceivable spheres of existence. The ideal geometry of cosmic bodies, which was revealed to us then, became the basis for building our own form. That is why I was so fascinated when, billions of years later, I met you among creatures. Each time, stepping into unknown matter, I did not leave that first feeling that arose at the beginning of the universe. Its forces, linking distant worlds, became like a bridge thrown over the sky, on which you and I were waiting for the sunset of the night …peering into the endless, dark distance and trying to find answers on the threshold of their exodus.” (Primitive Creation. Rev. 181)
