Dear friends, let's talk about a very interesting topic today: the universe is 13.8 billion years old, and there are countless 2 trillion galaxies in it! Of course, there are countless stars in each galaxy, and basically every star is surrounded by a large number of asteroids, comets, and a few cute asteroids. Have you ever wondered if there are some "extraterrestrial friends" like us humans in such a vast universe, and if so, why have they never visited our lovely earth?
To be honest, scientists still don't have a definitive answer to the question of whether aliens exist or not. However, according to their professional analysis, the various speculations can be broadly divided into three hypotheses. The first is to think very bluntly: there are no aliens at all, and life is a rare existence in the entire universe, let alone intelligent life. You must know that in order for life to be born and develop, it needs to meet many strict conditions. You see, it's not easy to survive in a universe other than the Earth's environment.
If you want to survive, you have to face many dangers such as cosmic rays, star falling, black hole swallowing, asteroid impact, toxic gas leakage, etc. Even if life is finally born because of various miracles, if you want to evolve to have the same high intelligence as us, you have to consider the probability intersection of thousands of variables. Therefore, some scholars feel that we humans can appear on this blue planet, just like an asteroid picking up a summer flower, it is really lucky! I am afraid that this probability will only happen once in the entire universe, so there is no alien thing at all!
The second hypothesis believes in the existence of aliens, but believes that the distance is too far away, and even if aliens are really high-tech, it may take millions of years to fly to Earth at the speed of light. It is conceivable that even if such a group of aliens really set off to Earth, no one dares to guarantee that they will be able to arrive while they are still alive. Moreover, even if the aliens do have the ability to come to Earth, how can we be sure that they are interested? What if in the eyes of the aliens, we humans are like a group of small ants crawling around in the forest, and there is nothing worth exploring and communicating?
So, those nerds often say that "the earth is like a grain of sand in the universe", and the aliens probably think that there is so much sand, so why bother to patronize us? Because even we humans on earth are not accustomed to ignoring some tiny existence? You see, we don't exploit ants, earthworms, and snails, but we don't bother to pay attention to their lives at all. It makes sense for aliens to think of us as little bugs on Earth.
The third hypothesis, however, is interesting. It believes that aliens not only exist, but have been here for a long time. Maybe there were aliens who visited the earth before humans evolved, but they didn't leave too many traces on the earth, otherwise we would have discovered it a long time ago. After all, the earth has existed for nearly 4.6 billion years, and in comparison, the time from the emergence of human beings to the present is just a flick of a finger. So, it's quite possible that over a long geological epoch, aliens will occasionally pass by our asteroid, isn't it?
Of course, it's easy to explain why they don't show up in public. Do you think, if you were aliens and saw a group of small creatures still in a period of ignorance, would you directly teach them aerospace technology and weapon manufacturing? Besides, there is also a tacit understanding between scientific and technological civilizations. Perhaps there is an agreement between aliens, that is, not to interfere with the natural development of those relatively backward civilizations, so as not to affect the diversity of civilizations in the entire universe. Otherwise, wouldn't the universe be boring?
Well, in general, it seems that it is difficult to fully convince us of either hypothesis. So, in the end, we have to think seriously with an open mind: Is there really any other life in the universe? If so, why have they never come to the earth? Is it too far away? Or are we humans too underestimated to them? Or have they actually been here a long time ago, but we just haven't discovered it? In any case, I hope that human civilization will become more and more developed, and one day we will be able to go out of the earth and find the answer to the universe for ourselves. By then, we might be able to meet our extraterrestrial friends!
Disclaimer: The information in this article comes from the Internet, which is not guaranteed to be completely correct and is for reference only.