astronomer
Albert einstein
When human beings walk out of the earth, they are full of infinite yearning and exploration interest in the vast universe. Before humans stepped out of the earth, we thought that the earth was an infinite space, so big that there was no boundary. However, with the progress of human science and technology, our understanding of the earth is also increasing, especially after stepping out of the earth, we finally understand: the original earth is only a very small planet.
In the past, we could not really understand the meaning of the word small, but when we stood in the universe and saw the unimaginably large universe, we really understood what smallness was. In the face of the vast universe, the earth is small, human beings are small, so how does such a vast universe work? Does it have boundaries?
In fact, for the mysteries of the universe, what scientists want to understand most is the operation law of the universe. To know that our solar system is very regular, the eight planets orbit the center of the sun, other asteroids will not run around, but have their own orbit. When we recognize the Milky Way, we also understand that the solar system is not stationary, but moves around the center of the Milky Way.
So if we zoom in on the entire universe, will there also be a center of the universe, and the other galaxies and celestial bodies are actually moving around the center of the universe? For this conjecture, we are not yet able to explore and understand, because the universe is too big, and the current observable 93 billion light-year universe range of human beings may be only a grain of dust in the vast universe.
So before human beings have the ability to travel all over the universe and reach the center of the universe, will we not be able to detect the rules of the universe? Of course not, in fact, we all know that the universe, from a macroscopic point of view, is composed of various substances, and the composition of matter is actually a variety of elementary particles.
Since human beings began to enter the field of microscopic exploration, we have also had a preliminary understanding of the rules of the universe. Since the universe is composed of various elementary particles from a microscopic point of view, it means that the rules of the universe may also be determined by the basic rules of microscopic particles. So what are the basic rules for particles?
To uncover the mysteries of the particle world, we need to enlarge the particles many times, enlarge a microscopic particle to the macroscopic level, and we can intuitively see the basic laws and rules of the particle world. After scientists have magnified atoms by tens of millions of times through instruments, a wonderful and mysterious world has appeared before our eyes.
The atoms that are magnified by tens of millions of times have also allowed scientists to discover a secret, that is, the basic operating laws of the microscopic particle world. We all know that an atom is very small, and if we don't amplify it by tens of millions of times, it's hard to see how it works inside. In the enlarged world of atoms, we first see the nucleus in the center, which is the focal point of the internal mass of the atom.
We all know the law of universal gravitation, the macroscopic world of matter has gravitational force, then the particles in the microscopic world naturally have gravitational force, the atomic nucleus occupies most of the mass of the entire atom, so other electrons need to move around it. This is very similar to the galactic motion of the macroscopic universe, where the solar system moves around the central sun and the Milky Way moves around the galactic center.
Since the inner world of atoms presents a very regular operating law, and this operating law has been verified in the solar system, the Milky Way and other galaxies, does it mean that the entire universe may also be orbiting around the center of the universe? In fact, scientists have speculated that the center of the universe may also be a celestial body with unimaginable mass, whether it will be a black hole or something else, we do not know at present.
From the movement of electrons around the nucleus inside atoms, we seem to see the basic laws of the universe. If this conjecture is correct, where is the center of the universe? This may start from the origin of the universe. Modern scientific theories suggest that the universe originated 13.8 billion years ago with the Big Bang at the singularity.
The location of this mysterious singularity may be the current center of the universe, because after the Big Bang, it expanded rapidly at the speed of light to the surrounding areas, thus forming a spherical universe centered on the singularity. The biggest possibility at the center of the universe is a black hole with a mass we can't imagine, and such a black hole may be far beyond the black hole we now know.
Of course, there are also doubts about this: if the center of the universe is a black hole with a mass so massive that we can't imagine, then the black hole should attract more stars and other celestial bodies, and then form a huge and bright accretion disk. If the accretion disk is bright, can't we observe it? You know, the first picture of a black hole of mankind is from a supermassive black hole 55 million light-years away.
But the current situation is that we have not observed such a terrible black hole, is the center of the universe not a black hole? In fact, many people have a misconception that humans can observe black holes, that is, as long as it is a black hole with a strong accretion disk, we should be able to observe it. However, many people overlook a very important issue, that is, speed.
We all know that the speed of photons is the speed of light, and the reason why human detectors can observe stars, planets, black holes and other celestial bodies is because the photons emitted or reflected by these celestial bodies themselves enter the field of vision of our detectors, and only when our detectors receive these photons, we can see some celestial bodies in the distant starry sky.
But let's not forget that the rate of expansion of the universe is different at different levels, according to the research of modern scientists, the moment of the big bang of the universe, produced a very terrifying and rapid expansion rate, so it can form the first huge universe in a short period of time. This speed is far faster than the speed of light, and after the end of the Big Bang, the speed of expansion of the universe has also dropped dramatically, but the rate of expansion at different levels is still different.
Scientists believe that the expansion rate after the Big Bang is still faster than the speed of light, especially those galaxies formed in the early days of the universe, their speed away from us has exceeded the speed of light, so we cannot observe these galaxies with optical telescopes, because the speed of photons is slower than the expansion rate and cannot enter the telescope's field of vision.
If so, then there are two scenarios in which a powerful black hole that might exist in the center of the universe is that the moment of the Big Bang produced a large amount of matter, and a large part of this matter remained in the center to evolve into an unimaginably large black hole. However, because the speed of the big bang of the universe is far beyond the speed of light, after the formation of the black hole at the center of light, there is no matter around, and those matter has left the center far away from the center, and it has begun to condense into various celestial bodies and galaxies in a very distant place from the center of the universe.
If this is the case, then it is possible that this black hole at the center of the universe has no accretion disk, only the most primitive mysterious singularity. Although there is no accretion disk, its mass is the highest in the universe. Another case, that is, the black hole at the center of the universe also has an obvious accretion disk, but because the rate of expansion exceeds the speed of light, the speed of energy photons emitted by the accretion disk is only the speed of light, and it is also impossible to enter the field of view of human telescopes, so we cannot observe.
If so, then only when human science and technology are further advanced, they can study other types of astronomical telescopes, such as gravitational wave telescopes, so that we can observe some powerful objects such as black holes, even if they do not emit light, they can be detected by gravitational waves. If there really is an unimaginably large black hole at the center of the universe, then its strong gravitational force will inevitably produce a very powerful distortion of the surrounding space, and this distortion will produce obvious gravitational waves, which may be detected by us.