The only thing expanding is space. That bread is space. Instead, these bits of banana galaxies getting pushed along and pushed farther apart because the break space is expanding between them. Indeed, we could say that each observer is at the center of their own universe. Therefore, if you use the light horizon to determine the center of the universe, you will always find it to be in roughly the same place as the observer.
You can find a really cool example of this effect here. Care about supporting clean energy adoption? Find out how much money and planet! By signing up through this link , Futurism. Share This Article. Next, there could be a center of curvature. Like a salad bowl, there could be a central point to the universe from which all other points curve away from. But current observations have found the universe to be flat and not curved at all.
Yet another possibility is a center of expansion. If you bolt a rubber sheet to the ground and then have people pull on all sides, the place where the sheet is bolted becomes the center of expansion. The center of expansion is the point in space from which all other points are moving away. A wealth of astronomical observations has revealed that the universe is indeed expanding. These observations are the foundation for the concept that a Big Bang started the universe.
Because the universe is expanding, if you run time backwards, there had to be a time when the universe was all compacted to one point. Since the universe is expanding, you would think there is a center of expansion. But observations have revealed this not to be the case. The universe is expanding equally in all directions. All points in space are getting uniformly distant from all other points at the same time.
This may be hard to visualize, but the key concept is that objects in the universe aren't really flying away from each other on the universal scale. Instead, the objects are relativity fixed in space, and space itself is expanding.
You might be tempted to say that the location of the Big Bang is the center of the universe. But because space itself was created by the Big Bang, the location of the Big Bang was everywhere in the universe and not at a single point. If the Big Bang happened at one location in space, we would only see this flash of light coming from one spot in the sky we can see a flash that happened so long ago because light takes time to travel through space and the universal scale is so big.
The objects that are very far away do indeed appear to move away from us at greater speeds than the nearby objects, but they also don't appear to be the same age as the slower, closer objects.
Instead, as we go to extreme distances, the farther ones appear younger, less evolved, greater in number, and smaller in size and mass. Despite the fact that we can see galaxies out to distances in excess of 30 billion light-years, if we track how everything is moving and reconstruct their trajectories back to a common origin, we see the most unlikely of outcomes: the perceived "center" lands right on us.
Our location lies on the outskirts of the Virgo Cluster large white collection near the Milky Way. Despite the deceptive looks of the image, this isn't a real structure, as dark energy will drive most of these clumps apart, fragmenting them as time goes on.
Yet if our Universe began with an explosion, the explosion's reconstructed center would lie right here: in this supercluster, which occupies less than one billionth of the volume of the observable Universe.
Our of all the trillions of galaxies in the Universe, what are the odds that we would just happen to be right at the center of the explosion that began the Universe?
What are the odds, on top of those minuscule ones, that the initial explosion was configured in just such a way, complete with. There's a lot we'd have to contrive to explain this, and many observations would still remain inexplicable.
The explosion scenario isn't just unrealistic; it's in defiance of the known laws of physics. An explosion in space would have the outermost material move away the fastest, which means it would It would also need to expand into something, rather than stretching space itself. Our Universe doesn't support this. Instead, however, the law of gravity that governs our Universe — Einstein's General theory of Relativity — predicts that a Universe full of matter and energy doesn't explode, but instead expands.
A Universe that's full of equal amounts of stuff everywhere, with the same average densities and temperatures, must either expand or contract; since we observe an apparent recession, the expansion solution is the only one that's physical. There's a misconception that an expanding Universe can be extrapolated back to a single point; this isn't true! Instead, it can be extrapolated back to a region of finite size with certain properties i. What this leads to, inevitably, is a Universe that has similar properties everywhere.
This means that in any finite, equally-sized region of space, we should see the same density to the Universe, the same temperature to the Universe, the same number of galaxies, etc. We'd also see a Universe that appeared to evolve with time, as more distant regions should appear to us as they were in the past, having expanded less and having experienced less gravitational attraction and smaller amounts of clustering.
Because the Big Bang happened everywhere at once a finite amount of time ago, our local corner of the Universe will appear to be the oldest corner of the Universe that there is. From our vantage point, what appears to us nearby is almost as old as we are, but what appears at great distances is much more similar to what our nearby Universe was like many billions of years ago.
When you look at a region of the sky with an instrument like the Hubble Space Telescope, you are not Hubble has taken us farther back than any other observatory to date, and has shown us a Universe that evolves in galaxy type, size, and number density with time. The distant galaxies that exist are constantly emitting light, and we are seeing the light that has arrived only after it has completed its journey to get to us through the expanding Universe. Galaxies whose light took a billion or ten billion years to get here appear as they were a billion or ten billion years ago.
If we go all the way back, towards almost the moment of the Big Bang itself, we'd find that the Universe when it was that young was dominated by radiation, and not matter. It has to expand and cool for matter to become more important, energy-wise. Over time, as that Universe expands and cools, neutral atoms can finally, stably form without being immediately blasted apart.
The radiation that once dominated the Universe, however, still persists, and continues to cool and redshift due to the expansion of space.
What we perceive today as the Cosmic Microwave Background is consistent with being the leftover glow from the Big Bang, but is also observable from anywhere in the Universe.
The large-scale structure of the Universe changes over time, as tiny imperfections grow to form the Looking to great distances reveals a younger Universe, similar to how our local region was in the past. Going back past the earliest galaxies we can observe, we find the leftover glow from the Big Bang itself, which appears in all directions and should be visible from anywhere in the Universe. There isn't necessarily a center to the Universe at all; it's only our biased intuition that tells us there ought to be one.
We can set a lower limit on the size of the region where the Big Bang must have occurred — it can be no smaller than the size of a soccer ball or so — but there is no upper limit; the region of space where the Big Bang occurred could even have been infinite. If there truly is a center, it could literally be anywhere, and we would have no way to know.
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