Hubble volume Hubble volume does not represent the shape of the universe, but an observable spherical region centered on the observer. Every position in the universe, including the earth, can be used as a central point, and a regional range of Hubble volume can be obtained from different positions.
We observe the universe from the earth, of course, is self-centered. At present, the Hubble volume is a sphere with a radius of 46 billion light years. Of course, this Hubble volume does not mean that we have observed as many as 46 billion light-years of stars as possible, but is calculated from the cosmic microwave background radiation data. The farthest galaxy we really observed is more than13 billion light-years away from the earth.
As for the true size of the universe, opinions vary. Some scholars believe that the diameter of the universe is 78 billion light years, which is smaller than the scope of Hubble volume, while others believe that it is 10 times the radius of Hubble volume. However, no matter what point of view, they basically agree that the universe may be limited, but it will never reach the boundary.
In short, if there is any doubt that the earth is located in the center of Hubble volume, it must be that there is no understanding of the concept of Hubble volume. Hubble volume can also describe the observable area of the universe centered on us.
Observation? Who observes? Of course, from our human point of view, it is us humans. If there are aliens in places we can't observe, their observation is also centered on them, and we humans are in the "horizon" relative to them.
Is it a coincidence that the earth is at the center of Hubble volume? Whether Baidu or Wikipedia, the size of the universe we search is 93 billion light years. No matter from any direction of the earth, the radius of the universe is 46.5 billion light years, and the earth is right in the middle of the universe! Is it really God's plan?
Starting from the geocentric theory, it is human understanding of the world, and the universe is round. Ancient sages concluded that the earth is the center of the universe by observing the movement of stars, and the great ancient Greek philosophers Aristotle and Ptolemy developed it into the geocentric theory that dominated human thought for thousands of years. From the perspective of seeing is believing, the earth is indeed the center of the universe, because the whole sky revolves around it.
However, this perfect theory has a huge loophole, because it is observed that the four planets are actually retrograde. However, because the geocentric theory is very close to the theory that God created the universe in the church, it was still popular for more than a thousand years even if it was wrong, until Copernicus discovered Heliocentrism. Since then, the discovery of the laws of planetary motion and the invention of telescopes have indirectly or directly proved the correctness of Copernicus's sun-centered theory!
However, with the in-depth understanding of the Milky Way by astronomers, it is found that the solar system is only one of hundreds of billions of star systems with galactic coefficient, and surprisingly, the solar system is not at the center of the Milky Way, but at the cantilever edge of Orion, about 26,000 light years away from the center of the Milky Way. If the whole city of Beijing is compared to the Milky Way, then the position of the earth is at least outside the Third Ring Road!
The universe is so big that I didn't know there were hundreds of millions of rings. What is the third ring? However, it is a big mistake to think that the earth is still the center. 1965 The discovery of cosmic microwave background radiation made it possible to measure galaxy motion on a large scale. 1977, goerge smoot of Lawrence Berkeley National Laboratory and others used the dipole anisotropy of cosmic microwave background radiation to measure the motion of the Milky Way, and found that the motion speed of the Milky Way was about 600 km/s!
Its direction of motion is a huge source discovered by the astronomical community in 1988, which is close to the gravitational centers of more than 400 elliptical galaxies and about 250 million light years away from the Milky Way. However, this position is blocked by a large number of stars and dust near the center of the Milky Way, and the astronomical community has always been curious about why this position has such a strong gravity! But you don't have to worry that the Milky Way will fall into this huge source one day. Due to the expansion of the universe, Ju Yuan is far away from the Milky Way at a speed of more than 4,000 kilometers per second!
Red circles are a great source of attraction.
How big is the universe? Does it have a center? Astronomers have always wanted to know this question, but until 1920s, our knowledge was limited to the Milky Way. It was not until Hubble determined that Andromeda galaxy was at least 165438+ million light-years away from us through the light change law of Cepheid variable stars that astronomers suddenly discovered that many nebulae that looked like the Milky Way were actually more distant galaxies, but they wanted to obtain the size of the universe by measuring the distance of galaxies. Endless, so there must be a theoretical breakthrough!
The Universe Revealed by the Big Bang Theory
In the above article, we mentioned the cosmic microwave background radiation, which is the real evidence of Lemaistre's Big Bang theory. In addition, there are two pieces of evidence, such as the expansion of the universe, which was obtained by Lemaistre and Friedman by deducing Einstein's gravitational field equation, while Hubble confirmed through observation that the universe is indeed expanding, and the farther the galaxy is, the faster the regression speed is!
Since then, the proportional distribution of raw materials at the birth of the universe and the initial nuclear fusion reaction after the Big Bang have also pointed out that there may have been an unimaginable Big Bang in the universe a long time ago, and the discovery of microwave background radiation has made this theory a real hammer! By observing the cosmic microwave background radiation and the expansion rate of the universe, it is estimated that the size of the universe is about 93 billion light years, but the optical Hubble volume is not that big, because the cosmic microwave background radiation is the limit of optical observation, and further discovery can only reach the core of the Big Bang through neutrino and gravitational wave detection technology.
Is the core of the Big Bang beyond the microwave background radiation the whole universe?
So far, the universe in the cosmic microwave background radiation is all we have seen, but astronomers are obviously not satisfied with this, because the outside world is the distance from BIGBANG to the expansion of 380,000 years, which can be calculated, but is the universe really only this big?
How to measure the size of the universe
It is obviously impossible to directly measure the curvature of space. The shape of the universe may be a closed sphere with different curvature. No matter how big it is, it is a limited space, hyperbolic infinite space, flat infinite space! Why can the shape of the universe be defined by this parameter?
Astronomers put forward these models for a reason. Einstein's formula of general relativity gravitational field was released in 19 16, and was applied to cosmology in 19 17. Among them, the earlier derivation of the Soviet physicist Friedman Lemaistre, H.P. Robertson and Volcker were in 1935 and/kloc respectively.
Friedman-Lemaistre-Robertson-Walker metric
Space curvature is not easy to measure, so astronomers use the comparison between the average density and the critical density of the universe to replace this parameter, which can also assist the expansion or static and collapse of the universe deduced from friedmann equations, because the universe in friedmann equations is expanding in most cases, while the modern universe is still expanding!
According to the observation and calculation results of cosmic microwave background radiation by multiple detectors, the critical density of the universe is almost equal to the average density, and the universe is flat on a large scale, which means that the universe is infinite in spatial scale! This directly broke our cognition, which is larger than our imagination from the perspective of Hubble's volume of 93 billion light years, but the measurement results of astronomers directly ruined the three views!
Why does it seem that we are in the center of the universe? To put it simply, the universe we observe is probably a corner, for example, in a Sahara desert, full of long yellow sand. So can we find ourselves on the edge of the desert or in the center? Just like human beings know the earth, there is endless flat land on the earth, but in space, it is only a sphere!
The limitation of observation technology gives us an illusion that we are in the center of the universe, but the so-called center of the universe is only frog's knowledge!
The fact that the earth is located in the center of Hubble volume is actually very complicated, which involves how we humans observe the universe.
The position of the earth in the universe is constantly changing with the improvement of human observation means.
In ancient Greece, the Greek sages at that time believed that the earth was the center of the universe and all celestial bodies revolved around it. In fact, it is intuitive to regard the earth as the center of the universe, because we live on the surface of the earth. From our observation point of view, the sun, the moon and the planets do revolve around the earth.
This is the embryonic form of geocentric theory, which was later perfected by Ptolemy and became a scientific theory.
The theory of geocentric theory accords with people's intuition and religious values, so geocentric theory ruled people for nearly 2000 years until Copernicus, Kepler and others established "Heliocentrism".
In fact, when Heliocentrism first put it forward, it was not very accurate. Later, Galileo discovered Jupiter's satellite with a telescope, which directly denied the "geocentric theory", because geocentric theory believed that all celestial bodies revolved around the earth.
Kepler deduced "Kepler's three laws" from the data observed by his teacher Tycho, making Heliocentrism the mainstream theory.
From the center of the earth to Heliocentrism, not only the scientific theory has changed, but also the position of the earth has changed, from the original center of the universe to an ordinary planet in the solar system. The appearance of Newton made the earth a negligible asteroid in the universe.
Newton's Law of Gravitation After Newton put forward the law of gravitation, he encountered an unsolved problem, that is, according to the law of gravitation, all celestial bodies will approach each other under the action of gravity, but the actual observation is not like this. For example, the moon is not getting closer and closer to us.
At this time, Newton encountered an irreconcilable problem. In order to solve this problem, he proposed that the universe is infinite, so that all parts of the universe have equal gravity, so that all celestial bodies will not approach each other. This is Newton's worldview: the static universe.
But soon someone questioned Newton's static universe, and he was Olbers. Olbers thinks that if the universe is infinite and static, then the distant starlight should converge on the earth, making the night as bright as the day, but in fact there are not so many starlight at night.
This question put forward by Olbers is called Olbers Paradox.
The dynamic universe is 1905, which is called Einstein's miracle year. During this year, he published four groundbreaking papers, each of which was an achievement beyond the Nobel Prize.
In one of them, Einstein put forward the general theory of relativity, but when he put forward the general theory of relativity, he found that the result of this formula was that the universe was dynamic, which was different from his world view, so he added a cosmological constant to this formula.
But Einstein was soon beaten in the face, and Lemaistre, a priest at that time, questioned him, while Hubble, another scientist, discovered the red shift of galaxies through a telescope, that is, some galaxies were moving away from the earth. Moreover, this distance has a certain rule. The farther away from the earth, the faster the rooftop retreats, which is the expansion of the universe.
Although Einstein skillfully added a cosmological constant to his general theory of relativity, this cosmological constant can describe the expansion of the universe as long as its value is reasonable. So the cosmological constant is preserved in general relativity.
According to the expansion of the universe, scientists can infer that the universe may have a hot beginning at first, so they put forward the big bang hypothesis.
After the Hubble Big Bang hypothesis was put forward, scientists wanted to know how the universe expanded. Results The data show that there is still an invisible force in the universe that leads to the accelerated expansion of the universe, and the expansion speed of the edge of the universe has exceeded the speed of light, which means that the light emitted by these galaxies will never reach the earth, and we will never be able to observe the boundary of the universe.
If the universe is regarded as the size of the earth, then human beings may be smaller than ants, and the range seen by ants is limited, which is called "Hubble volume" in its field of vision, but Hubble volume is not the whole universe.
With the current means, we can only observe the universe with a diameter of 96 billion light years, which is the so-called Hubble volume. It is no coincidence that the earth is located in the center of Hubble volume, because Hubble volume is defined by human beings and is a universe centered on the earth.
And the size of Hubble can be further expanded with the improvement of human scientific and technological means, but in any case, we can't see the whole picture of the universe.
It's really excellent to come up with this question. Because I found a similar problem when I was 4 years old, which once made me think I was the chosen one!
It was a summer night in the early 1990s. When I was 4 years old, I played in the yard with my cousin who was 3 and a half years old. There was no smog at that time, and the bright moon overhead was even a little dazzling.
Accompanied by moonlight, my sister and I chased each other in the yard, laughing and playing.
Suddenly, I found it! When I run, the moon above me is following me!
Young me, I was stunned by this amazing discovery! Almost at the same time, I told my sister the shocking secret.
"Elder sister, look! When I run, so does the moon! It's amazing! "
My three-and-a-half-year-old sister obviously doesn't understand what I'm talking about. At that time, her expression was like this:
However, immersed in the same joy as Columbus' discovery of the new continent, he was completely unaware of his sister's depression. At that time, my heart was faintly swollen and I thought she was admiring.
"Really, you see, it's amazing! You run and have a try! " I am positive color way.
My sister, who was obedient to me since childhood, trotted out.
I quickly looked up at the moon.
What puzzles me is that the moon didn't move this time.
What do you mean? Moon, go! How can I behave like this in front of my sister? What if she doesn't worship me anymore?
"Stop! Sister. Wait a minute. "
Sister:
For an instant, I had doubts about myself again. Is it my illusion before? No, I have to try again.
I looked up at the moon. Afraid it will lie to me again.
I ran to find my sister.
The moon is moving again!
I finally understand! It turns out that the moon only runs when I run! No one else will! That explains everything!
At that moment, I shed tears of excitement.
At that moment, the moonlight hit me like a spotlight.
At that moment, I was convinced that I must be the only thrill sent by heaven to save mankind.
Well, the answer to this question is obvious: yes! What a coincidence! The earth is the celestial sphere chosen by the universe!
According to the observation of modern astronomy, the earth is indeed located in the center of Hubble volume.
Blocked by the galactic silver disk, only the universe within 150 degrees above and below the silver disk can be observed.
This is the so-called Hubble volume, a sphere with a radius of about 48 billion light years.
About the position of the earth in the universe, human understanding has experienced ups and downs, and then ups and downs.
After every fall, it is accompanied by human deep thinking about the nature of the world.
At first, when science was just developing. Early philosophers have realized that the earth is round.
Italian missionary Matteo Ricci (1552~ 16 10) entered China with a globe in 1583.
People at that time asked him, if the earth is round, why don't the people below fall down? Matteo Ricci can't answer this question.
In ancient Greece, philosophers realized that the earth might be round. Because, if the sunlight is regarded as parallel light, the radian of the earth will also affect the projection angle of the object on the ground. Objects far away from the sun will have a longer shadow in the sun.
Pythagoras used this principle to calculate that the circumference of the earth is 48,000 kilometers.
We now know that the equatorial circumference of the earth is 40075 kilometers, and Pythagoras can calculate such accuracy, at least on the order of magnitude, which is remarkable.
The diameter of the Milky Way is about 200,000 light years, and the solar system where the earth is located is about 25,000 light years away from the center of the Milky Way.
Dozens of galaxies, such as the Milky Way and Andromeda Nebula, make up the local galaxy group, and the center of the local galaxy group is probably between the Milky Way and Andromeda Nebula.
In about 5 billion years, the Andromeda Nebula and the Milky Way will merge.
Because we can't see the whole picture of the Milky Way, it is generally believed that Andromeda Nebula is bigger than the Milky Way. But in fact, the Milky Way may be bigger than Andromeda, or it may be much bigger.
At present, the mass of galaxies is calculated, and the Milky Way is larger than Andromeda. The escape speed of the Milky Way is 550 kilometers per second, and the escape speed of Andromeda is 470 kilometers per second.
Virgo supercluster consists of 1000 galaxy clusters, such as the local cluster.
Virgo supercluster, also known as local supercluster, spans about 1. 1 100 million light years, and its center of gravity is in the direction of Virgo.
Virgo supercluster, the Serpent Centauri supercluster and the Peacock Indian supercluster form the Ranyakaya supercluster.
This is the largest primary structure in the universe. It looks like a feather and spans 520 million light years.
Ranyakaya's center of gravity is located in Ophiuchus.
There is a huge gravitational source that attracts the Milky Way to run at a speed close to 1000 km per second.
But the Milky Way will never get there, because the space between the Milky Way and Ju Yuan is expanding at a speed of 3,000 kilometers per second.
If you look at the structure of Rania Kaya, the earth is not in the center anyway. But in the whole observable universe, the earth is the center. How do you explain this?
Because, if any point in the universe looks around, it will find itself in the center. This is because the universe has an extraordinary shape.
If we stand on the ground and look around, we will find that the horizon is surrounded by a circle, and the observer is located in the center of this circle.
A closed two-dimensional sphere like the earth, any point is the center point.
From 65438 to 0922, after the seventh anniversary of the publication of general relativity, Alexander Friedman, a mathematician and physicist in the former Soviet Union, gave a profound mathematical description of the evolution of the universe according to the general relativity.
According to the different curvature of space, the shape of the universe can have three situations.
In the plane coordinate system, the sum of the three internal angles of a triangle is 180 degrees. If the sum of the three internal angles of a triangle is less than 180 degrees, then the curvature of the space is positive; If the sum of internal angles is greater than 180 degrees, the spatial curvature is negative.
If the curvature of the universe is negative, then the universe is a hyperboloid structure with a starting point and infinity. If the curvature of the universe is 0, then it is a structure with no beginning and no end. When the curvature of space is positive, the universe is a finite closed structure with a starting point.
If we go back 65.438+038 billion years, the universe will shrink to a point, which is the starting point of the Big Bang.
According to the latest observation of the curvature of the universe by the European Planck satellite, the curvature of the universe is positive.
And according to the measured data, scientists believe that the universe is a sphere, a four-dimensional hypersphere. The universe lies on the three-dimensional surface of a four-dimensional hypersphere.
So it is no coincidence that the earth is located in the center of Hubble volume, which is determined by the shape of the universe.
According to this reasoning, if we go straight in any direction in space, we can go home as long as we spend enough time.
This universe is infinite, and human beings only have this observation ability! Just like a blind man touching an elephant!
What's more, the motion of the universe is not a simple linear or curvilinear motion! The motion of this universe is binary opposition, and the extremely complex motion mode of the virtual and real universe constitutes a complete form of motion!
This shape looks like a huge ellipse, but what makes us subvert the three views is that our material universe is actually a cone!
The mirror image of the physical universe, the virtual universe is also a cone of the same size!
The cone vertices of the virtual and real universe are vertically butted together and rotate reversely around the same axis!
At a certain limit, the two universes will return to compression and run towards the origin! This origin is equivalent to the mathematical coordinate 0!
While the two universes are rotating in opposite directions, the horn formed by the expansion of the universes is still moving relative to Apollo.
At the same time, the two opposing universes are in an all-round circular rotation state! It also formed a big trajectory. How long does it take to run a big Sunday? Unable to calculate!
Two virtual and real universes are called two dimensions! Add a circular rotating force field and it will be three-dimensional! Coupled with the human stream of consciousness to form the so-called four-dimensional! Plus infinite time is five dimensions! There are no other dimensions!
No matter how many dimensions, they are actually negative! The absolute value of positive and negative is equivalent to ten dimensions!
The so-called scientists invented ten dimensions and eleven dimensions? Are all unscientific! It's a fantasy! It is contrary to the actual situation of this universe!
This round and seamless sports situation and infinite time and space make human beings confused forever!
However, according to human wishes, the earth is indeed in the middle of the universe!
What does the universe revolve around? This mystery makes him a mystery forever! A day when mankind has not cracked it!
When human beings understand that human consciousness is a very powerful force! Beyond everything!
And know and master this power!
Then human beings can have a future!
Lingbao Tianzun Liang Yukun upholds heaven.
According to modern science, our universe was born in the singularity explosion 65.438+038 billion years ago. In a very short period of time, the universe experienced skyrocketing, and then gradually expanded gently. The current expansion speed of the universe can be reflected in Hubble constant. The latest Hubble constant value is 7 1 4 kmspc, which means that the speed of their separation from each other will increase by about 68 kilometers every 3 million light-years of space and observers. Accordingly, when the distance between space and us exceeds about/kloc-0.4 billion light years, the speed of space retreating from us will exceed the speed of light. Theoretically, when we can receive the farthest light, the object that emits this light is 46.5 billion light years away from us, which is also the radius length of our Hubble volume.
Hubble volume refers to a sphere in the universe with the observer as the center and the distance from which the light emitted by an object has enough time to be received by the observer as the radius. So, if the observer is on the earth, then obviously the earth is the center of Hubble volume, and if the observer is on Mars, then the center of Hubble volume is Mars for the observer. In other words, no matter where you are in the universe, you will form a Hubble volume centered on yourself. In addition, the size of Hubble volume is the same anywhere in the universe, because the universe as a whole is isotropic, and the Hubble volume range formed by each observer at this moment may overlap, but the scale is the same.
In a word, the center of Hubble volume is determined by the observer. If you land on the moon one day, the moon will become the center of your Hubble volume.
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The universe is an infinite space. Observing the universe from the earth, the earth is not the center, and the universe has no center. The earth is also running, and the center of the earth should be adjusted. The center of the earth is not a coincidence, but an inevitable center.
No, it's inevitable. Your observation range is 100 meter. The range you can observe is a circle (ball) with a radius of 100 meters. No matter where you observe, you are in the center of the observable range. Although this question is meaningless, I decided to answer it for you.