The mystery of the universe is hidden in these 10 places

   Since its birth in the big bang 13.8 billion years ago, our universe has experienced a magnificent and colorful evolutionary history. Although many details have been grasped by us, as Socrates said, “The more you know, the more you don’t know.” There are still many things in the universe that are as confusing and scratchy as possible …
   Starting from this issue, we will introduce in series the 10 largest and most exciting mysteries in the universe, involving planets, stars, galaxies, black holes, and other strange and interesting topics. Let’s start now.
   3.
   What is Supernova SN 2017CBV ?
   Explosive death of stars
   where is it?
   5.5 million light-years away from our galaxy NGC 5643
   mystery involving the
   universe what kind of outcome?
   When the astronomer’s gaze crosses the vast universe and sees a star dying, he will routinely remove it from the star list. Because such things are not uncommon, they happen millions of times a day in the universe. But slowly, they realized that some things were not so simple.
   In March 2017, during a regular night sky inspection, David Sander of the University of Arizona found an anomaly. At first glance, it’s just another type of Ia supernova, the white dwarf, which is nearing its end after an excessive expansion.
   A white dwarf is a very dense celestial body. It is the wreckage left after the star burns out, and is mainly composed of carbon. As the wreckage of stars, the material inside white dwarfs is no longer nuclear fusion. But it usually has a mass limit. Above this limit, under stronger gravitational forces, fusion will reignite, turning the carbon inside it into a heavier element.
   White dwarfs are usually binary systems that appear in pairs, one sucking food from the other. If you eat too much, the “vampire” will exceed its mass limit, so it is equivalent to a runaway thermonuclear bomb that suddenly becomes very dazzling in a few seconds. This is the type Ia supernova explosion.
   Just because the mass limit is exceeded, and the mass limit is fixed, astronomers can predict the radiant energy generated by a type Ia supernova explosion and then compare it with the brightness it looks to calculate it and ours. Actual distance. In this way, type Ia supernovas have acted as “milestones” in the vast universe, and they have “measured scales”.
   That night, the SN 2017CBV that Sander observed was a type Ia supernova. But what’s strange is that subsequent extensive observations of it revealed that the companion of that exploding white dwarf was not another white dwarf, but a larger star! When the companion is a white dwarf, all the light emitted by the supernova explosion comes from the exploding white dwarf (the other white dwarf that does not explode does not emit light), and its brightness is a fixed value. According to the brightness measured on the earth, we can Know how far it is from us. But if the companion is a star, then because of the long distance, the light of the exploding white dwarf (supernova) is indistinguishable from the light of the star, and we have no way to know the true brightness of the supernova. In this way, it will not be able to act as a “sky scale.”
   this point is very important. The reason why we can use type Ia supernova as a “sky ruler” is because it was previously thought that type Ia supernova explosions have only one type of explosion. Now suddenly there is another explosion mechanism that has not been known so far. Two different type Ia supernovas are mixed together and it is not easy to discern. Then the accuracy of these “meters” is greatly reduced.
   The serious consequences of the unreliable “Measurement Ruler” are beyond your imagination-this shakes the core of cosmology! Because it involves the question of whether dark energy really exists.
   In 1998, astronomers discovered a group of distant type Ia supernovae, which were dimmer than expected, and concluded that they were farther than expected. Astronomers attribute this result to the accelerated expansion of the universe. They called the “dark energy” the unknown that caused the expansion of the universe to accelerate.
   No one knows what “dark energy” is, so far, it’s the opposite of gravity. Gravity holds matter together, but dark energy pulls them apart. This means that the contest between dark energy and gravity determines the size, lifespan, and final outcome of the universe. If dark energy is strong enough to overcome gravity, it will lead to a “big tear” ending. But if gravity wins, it will lead to the end of the “big collapse”.
   However, the hypothesis of “dark energy” is itself based on trust in type Ia supernovae, and it is believed that they can accurately serve as the “measuring scale” of the universe. If this basis of trust no longer exists, then everyone has talked about “dark energy” for so many years, and they can only count on ghosts. The Nobel Prize awarded for the discovery of “dark energy” should also be collected. There is no force in the universe that can compete with gravity, so there will be no ending other than the “big collapse” … this is no wonder that abnormal supernovas like SN 2017CBV are frowning.
   4, BOSS long wall of galaxies
   what it is?
   Large-scale structure
   where is it?
   It meanders in a wide range of sky, an average of 6.8 billion light-years away from our
   mystery involved
   we are in the universe in a
   special place?
   The entire cosmology is based on the notion that we have nothing special: in terms of location, the solar system is just a very common star system in the universe, and the earth is just an ordinary planet Humans are not placed in a special place in the universe.
   This point goes back to Copernicus’s great discovery: It’s not the sun that orbits us, but we are orbiting the sun. All of a sudden, we fell off the center of the creation.
   Since then, it has become increasingly clear that the earth and the sun are nothing but ordinary elements in the universe. Copernicus’ discovery has also become the “Copernicus principle”: Generally speaking, there is nothing special in the universe, everything looks the same. Our current model of the universe based on general relativity also relies heavily on this assumption.
   The core of Copernicus’s principle is the concept of scale. Think of the universe as a group of people. Looking closely, you can see that everyone has a different personality and hobby, but if you zoom out, the personality characteristics are blurred. What you see is just a group of people with no difference.
   One more analogy can be made. Sprinkle a bowl of peas randomly on the floor of the room. We know that every bean is composed of molecules, which are composed of atoms, and atoms are composed of nuclei and electrons … On a scale smaller than a pea, there is a layered hierarchy. But at the scale of peas, the grade disappeared, and there was no larger structure than peas (Of course, if you put peas in a bowl and then place a mouthful of bowls on the ground, compared to “a pea”, “A bowl of peas” is again a larger structure). What we see is that the peas are evenly distributed on the ground. So from the scale of peas, it can be considered that the material is evenly distributed.
   By the same token, on a smaller scale, the universe looks very unique, consisting of stars, galaxies, and galaxy clusters, but by a certain scale (generally about 1 billion light years), these differences have disappeared. Matter appears to be evenly distributed throughout the universe.
   But in recent years, various challenges to this view have emerged. Perhaps the biggest challenge is the long wall of the BOSS galaxy discovered in 2016. The “wall” is made up of thousands of galaxies, a giant filamentous structure that stretches up to 1 billion light years.
   The Virgo Super Galaxy Cluster, including our Milky Way galaxy, also appears to belong to a larger structure called the “Rania Kea Super Galaxy Cluster”. This large super galaxy cluster was delimited in 2014, and it spans 500 million light years in the sky. In the same year, we also found a giant hollow in the sky with a diameter of 2 billion light years.
   All in all, we may occupy a rather unusual place in the universe, between a huge super galaxy cluster and another huge cosmic cavity. Such a scene “configuration” may be relatively rare in the universe.
   There is no conclusion on whether the cosmic matter is evenly distributed. If larger structures continue to appear than the BOSS galaxy wall in the future, the homogeneity hypothesis is at stake.
   Moreover, the existence of giant structures may force us to abandon the idea of ​​space and time to be uniform. As a result, the estimation of the current age of the universe will also change. There are currently two competing methods for measuring the expansion rate of the universe. One is calculated based on the cosmic microwave background radiation. Because this radiation was originally a high-energy photon with a short wavelength, it was later elongated with the expansion of the universe, so its extension is related to the expansion rate of the universe; the other is based on the expansion rate of the universe. The degree of supernova brightness decays with the expansion of the universe. In the past, because the accuracy of the two calculation methods was not high enough, the difference between them seems to be within the allowable range, but now, as the accuracy increases, the difference has exceeded the allowable range. Astronomers have no way of judging which one is more accurate. Perhaps the existence of giant structures is the cause of this disagreement. If confirmed, then this will further affirm the non-uniformity of the material distribution in the universe, and thus more affirm the particularity of our position in the universe.