Interstellar travel has always been a regular in science fiction, but when we dig deeper into the vastness of the universe and the fundamental laws of physics, we will find out:Interstellar travel is almost impossible to achieve.
Because the distance between cosmic bodies is beyond the limits of human imagination, for example, Proxima Centauri, the closest star to the solar system, is 266,000 times the distance from the Earth to the Sun, and even 300,000 kilometers of light per second has to fly 422 years, what is even more terrifying is that the speed of light is the upper limit of the speed of the universe.
The farthest Voyager 1 probe is still traveling at 17 kilometers per second, and it will reach as fast as 7The most frightening thing about reaching Proxima Centauri 50,000 years later is that there is no essential breakthrough in today's space propulsion technology compared to Voyager 1, which highlights the limitations of traditional chemical-fueled rocket technologyDespite the concerns about nuclear fusion, positive and antimatter annihilation, and lightsailing spacecraftand other concepts have been hyped, but they are still in the theoretical stage, and they are still far from practical application.
Even if the technical hurdles are overcome, Einstein's theory of relativity sets fundamental physical limits for interstellar travel, as it proves that no object can exceed the speed of light, and that the spacecraft's mass will continue to expand as it approaches the speed of light, eventually requiring infinite energy to accelerate to the speed of light, and there can be no infinite energy in the universe, so neither the speed of light nor the speed of light is impossible.
In addition, the theory of relativity predicts the phenomenon of time dilation, which means that time on a spacecraft will pass more slowly than on Earth when traveling at speeds close to the speed of light, which is a good thing in the sense that it is goodBecause astronauts are flying at near the speed of light for a few yearsThe time dilation effect will make him a few dozen light-years away, the only problem is that by the time he returns to Earth, thousands or even millions of years may have passed on Earth.
And if in the eyes of high-level alien civilizations, all of the above is just a technical problem or can be solved, today, 13.8 billion years after the birth of the universe, other civilizations in the universe should have left traces in the entire universe or the galaxy, but the fact is nothing, the entire universe is silent.
This may hint at a simple but profound truth: the speed of light is the upper limit of the speed of the universe, so no matter how advanced an extraterrestrial civilization is, it cannot exceed the speed of lightNot in the entire universe or in the entire galaxyLeave enough traces to be discovered by human civilization.
Therefore, there may be many alien civilizations in the real universe, and even many alien civilizations whose technology far exceeds that of human civilization, but because the speed of light is the upper limit of speed and information transmission, the final effective radiation range of alien civilizations with advanced technology is only a few light years or dozens of light years, and the alien civilization itself will begin to ** after exceeding this distance, because the communication time difference of hundreds of years is enough to make any civilization divide because the range is too large.
Although interstellar travel is an eternal dream of mankind, it seems to become unattainable when we are faced with the vastness of the universe and the limitations of the laws of physics.
However, this does not mean that we should give up exploring the universe, but rather it should inspire us to continue to push the boundaries of science and find new theories and technologies, and perhaps one dayWe were able to make interstellar travel possibleAnd until that day comes, we will continue to explore the mysteries of the universe through telescopes, probes, and continue to search for evidence of life and intelligence in the corners of the universe that we can reach.