Today, all of us will discuss the last question. In fact, most people have an understanding of the existence of extraterrestrial life, because the diameter of the Milky Way is 200,000 light years, and the observable diameter of the universe is 93 billion light years. There are hundreds of billions of stars in the Milky Way alone, and there are countless stars in the whole universe. Having stars means having planets and large satellites. When a planet is in a livable zone, there may be stable liquid water and satellites.
There have been many UFO incidents on the earth, and everyone agrees that it is alien ufo. In fact, this is not rigorous. There are many explanations for UFOs, the most common ones are the repeated refraction and reflection of light, the illusion caused by psychological or visual fatigue, and even some undisclosed aircraft in some countries. Of course, it may also be an intelligent aircraft of alien civilization. Humans have found clues in some ancient books or murals that aliens may have come to the earth in ancient times. Look at the murals left by Mayan civilization below, just like an astronaut.
It is also recorded in China's ancient books. For example, "Han Ji-Chronicle of Emperor Wu of Han Dynasty" records that "there was a day and night in April", which shows whether there were planes or something in ancient times. It is likely to be a UFO event, and of course it may also be a supernova explosion. In ancient times, there were also hats and hats, and this modern UFO is exactly the same. Therefore, UFO incidents often occurred in ancient times, and it is not necessarily that UFOs visited the earth in ancient times.
There are several hypotheses about aliens:
1, mixed residence theory
This view holds that aliens live on the earth and live and study with humans. Some people even think that shooting with a special new radiation camera can reveal that some people may have a light blue halo around their heads. Of course, this statement is more inclined to science fiction, and there is no scientific basis. In addition to humans, they are also thought to exist on the back of the moon or at the bottom of the ocean in the center of the earth.
2. Parallel world theory
This statement is also a lot of speculation, but it is closer to science. For a long time, some scientists and scholars have proposed the multiverse or parallel universe. People believe that the universe we live in is not unique. At the beginning of BIGBANG, there were many universes at the same time, so it is very likely that different lives were born in different universes, that is, aliens were in parallel worlds.
3. The theory of human ancestors
This view is out of fashion now, because the theory of evolution holds that all creatures on the earth are homologous, especially the development and progress of genetic engineering in modern society. For gene sequencing, it is found that the genetic similarity between humans and chimpanzees is over 98%, and that between humans and bananas is over 50%, which is enough to prove that the creatures on the earth are homologous. But some people firmly believe that human beings were transformed by aliens and put on the earth. Of course, there are many such statements in the current literature.
4. Multidimensional space theory
Now the environment we live in is four-dimensional space-time, that is, three spatial dimensions plus one time dimension. However, there are also theories that there are high-dimensional spaces besides the world we live in. The string theory developed in the last century initially thought that the universe was a 26-dimensional space-time, but with the addition of supersymmetry, the superstring theory that the universe was a 10-dimensional space-time was formed. The latest theory was M theory, which integrated superstring theories in five different situations and proposed that the universe was a 1 1 dimensional space-time. If every dimensional space really exists, then there may be high-dimensional space creatures, then there will be aliens in high-dimensional space, and the control ability of high dimensions is several orders of magnitude higher. Is the so-called God a high-dimensional creature?
There are many speculations about extraterrestrial life and alien civilization, but there is no definite evidence so far. Although most people firmly believe that aliens must exist, there is also Fermi paradox. Aliens exist, so where are they? In any case, with the development of human civilization, one day these will no longer be mysteries.
Text/Du Ruo, image source network invasion and deletion.