In the exploration of the universe by human beings, interstellar travel has always been a fascinating vision, but with the continuous development of science, more and more experts believe that the speed of light is the upper limit of the universe, and interstellar travel is impossible.
Why do experts make such statements?
The speed of light, which refers to the speed at which light travels in a vacuum, is usually expressed as 299,792,458 meters per second, and this value is recognized in the theory of relativity as: the fastest speed in the universe, and is defined as the speed of light constant. The importance of the speed of light, embodied in the theory of relativity and cosmology, is essential for our understanding of how the universe is structured and operates.
In the theory of relativity, the speed of light plays a crucial role. According to Einstein's theory of relativity, the speed of light is constant in a vacuum and is not affected by the state of motion of the observer. This means that no observer can exceed the speed of light at any speed, regardless of his or her own state of motion. This principle has led to many important conclusions of relativity, such as time dilation, length contraction, etc., which has profoundly affected our understanding of time and space.
In cosmology, the importance of the speed of light is also reflected in the way we observe the universe.
Since the speed of light is the fastest in the universe, the light we observe from distant celestial bodies is, in fact, the light they emitted in the past. For example, when we look at distant galaxies, we actually see what they looked like millions or even billions of years ago. And this phenomenon is known as the optical travel time effect.
The existence of the speed of light also has an important impact on interstellar communication and interstellar travel. This is mainly because the speed of light is the maximum speed limit for information transmission, so communicating over long distances, or traveling, in the universe will be extremely challenging. Even speeds close to the speed of light require enormous energy and time to achieve. Therefore, the speed of light is considered a kind of upper limit in the universe, limiting human exploration and activities in the universe.
Interstellar travel refers to the act of exploration and travel by humans, or other living beings, in interstellar space. It involves traveling across vast cosmic distances across galaxies and interstellar space in search of new planets, stars, or other cosmic objects and exploring unknown mysteries of the universe.
The concept of interstellar travel has always sparked people's imagination and curiosity. In science fiction, interstellar travel is often portrayed as an exciting and romantic adventure in which explorers travel across the stars, explore unknown planets and civilizations, communicate with extraterrestrial creatures, and discover new science and technology.
However, in reality, the realization of interstellar travel will face huge technical challenges and limitations.
First of all, one of the biggest challenges is the limitation of the speed of light. According to the theory of relativity, the speed of light is the highest speed in the universe, and no object can move faster than the speed of light. This means: even the most advanced spacecraft will take years, if not decades, to reach the nearest interstellar target, such as the Alpha Centaur System, the closest galaxy to Earth.
Secondly, interstellar space is full of various dangers and unknown factors, such as cosmic rays, interplanetary atmospheres, black holes, etc. Spacecraft need to have adequate protection and survivability to deal with these threats.
In addition, interstellar travel has to deal with energy, food, life support systems, and more. Spacecraft must be able to provide enough energy and resources to sustain long voyages and survive.
Still, interstellar travel inspires curiosity and a spirit of exploration. Scientists are constantly exploring new technologies and methods to solve various challenges in interstellar travel, such as gravitational control, wormhole traversal, photon propulsion, and more.
Although there are still many difficulties and limitations in interstellar travel, with the continuous progress of science and technology and the exploration of the universe by human beings, perhaps one day, interstellar travel will become a reality.
But why do experts think that interstellar travel is impossible? Where's the basis for that?
The main reason why experts have such an idea is because the speed of light is the upper limit of the universe. According to the theory of relativity, a particle with zero mass, such as a photon, moves at the speed of light, while an object with mass cannot reach, or exceed, the speed of light.
Even speeds close to the speed of light can suffer from severe time dilation and mass gain, making interstellar travel impractical.
And even if humans were able to design a spaceship that could approach the speed of light, it would take a lot of energy and time to travel through interstellar space. Current science and technology, in fact, are far from reaching this level, and with the current level of scientific knowledge and technology, the resources and conditions required to achieve interstellar travel are unimaginable.
Another point is that there are still many unknown risk factors in interstellar space, such as cosmic rays, black holes, interstellar dust, etc., which increase the difficulty and risk of interstellar travel.
To sum up, despite the fact that interstellar travel is portrayed so beautifully and exciting in science fiction works, it is still considered impossible based on the current level of scientific theory and technology. After all, the limitations of the speed of light, the need for energy and time, and the unknown dangers of the universe make it an unattainable dream.