However, the scale of the universe is too huge. Even if humans can reach the speed of light, it will take 65438+ million years to cross the Milky Way. Therefore, if human beings really want to explore the universe, they must avoid Einstein's speed limit and find a way of space travel beyond the speed of light. Wormhole theory and warping drive are both methods that exceed the speed of light. The main method is to shorten the distance between destinations by changing the space, which is similar to "cutting corners".
In the laboratory, scientists also let the particle speed exceed the speed of light and discovered the Cherenkov radiation phenomenon.
Can light reach the fastest speed in a vacuum environment? Light has wave-particle duality, and it is an electromagnetic wave, which behaves like a particle. Because of the wave-particle duality of light, the propagation speed of light in a vacuum is the fastest, because there is no limiting factor that can stop light, but when light passes through a medium, whether it passes through a magnetic field or an object, it will produce resistance to the speed of light.
Just like the most familiar prism experiment, white light propagates at the same speed in a vacuum environment, but when the white light enters and passes through the prism, the prism will refract all kinds of light to different degrees according to different wavelengths, and then various colors of light will appear. Light with a longer wavelength (red light) has a lower frequency, while light with a shorter wavelength (blue light) has a higher frequency. The speed of light is the frequency times the wavelength.
However, in the prism experiment, scientists noticed that the propagation speed of red light is obviously slower than that of blue light, and blue light has more energy in the medium.
Media can slow down the speed of light, which enables scientists to find a way to go beyond the speed of light.
Most particles in the universe have mass. According to the theory of relativity, these particles can't reach the speed of light, and the massless particles in the universe have their own characteristics. In order to confirm the theory of relativity, scientists accelerate a single particle in a particle accelerator and apply huge energy to the particle, so that these particles move rapidly in a vacuum environment.
However, no matter how much energy scientists apply to particles, the speed of particles can only reach 99.999% of the speed of light. If you continue to apply energy, you can only make more "9" behind this data, and you will never reach 1 0,000% of the speed of light. More precisely, we will never reach the speed of light in a vacuum environment.
If particles do not accelerate in a vacuum environment, but compare with the speed of light passing through a medium, can the speed of particles exceed the speed of light?
When particles pass through a medium, the speed can exceed the speed of light? When light passes through the medium, the electromagnetic field and the characteristics of the object will affect the speed of light, and these effects will take effect immediately, and the speed of light will change immediately, so the speed of light depends largely on the characteristics of the propagation medium.
But particles are different from light. When a particle passes through a medium, its momentum will not change immediately, because the particle itself is close to the speed of light and carries a lot of energy. The influence of medium can be ignored in a short time, just as we hold a magnet, it is difficult to have a direct impact on the fast-moving train. In order to change the motion state of particles, direct interaction such as collision is often needed to produce obvious changes.
When light enters the medium, it will slow down, and particles will continue to move at almost the same speed after entering the medium. At this moment, the speed of particles can exceed the speed of light, which has been confirmed in the laboratory. When the speed of particles in the medium exceeds the speed of light, it will produce blue fluorescence-Cherenkov radiation.
Cherenkov radiation was originally thought to be a fluorescent reaction caused by the activation of experimental media by huge energy, but scientists soon discovered that this blue light was not a fluorescent reaction, but a brand-new phenomenon.
When particles move very fast, they are usually charged. When a particle passes through a medium, it is less likely to directly collide with the particles in the medium, but charged particles will have an impact on the particles in the medium-similar to the repulsion of two poles and the attraction of different poles. These changes only occur when the particles pass through. When particles pass through the medium, they will return to the basic state, and the transition phenomenon in this process is the reason of Cherenkov radiation.
Cherenkov radiation is a very important physical phenomenon. Using Cherenkov radiation, scientists can create a huge medium and receive high-energy particles from the universe, so as to detect various particles traveling through the universe and judge the energy and direction of the particles. In order to avoid the interference of the medium itself, all media need to use very pure special liquid, which is not radioactive and will not produce high-energy particles, ensuring that all data come from cosmic particles.
Cherenkov radiation proves that the speed of light is not insurmountable. This kind of radiation is a kind of electromagnetic radiation dominated by short wave. Where this phenomenon is found, many physicists will directly observe this radiation with the naked eye. With the emergence of radiation safety training, this process was terminated, and physicists could directly detect Cherenkov radiation with scientific instruments.
Scientists have surpassed the speed of light in the medium, and gained rich returns from Cherenkov radiation. Although the experiment did not surpass the fastest speed in the universe, it was still an outstanding scientific achievement. If human beings can really surpass the speed of light in a vacuum in the future, then human science will enter a new field. By then, humans may be able to master time and space and even reach a higher dimensional world.
Summary: The speed of light in a vacuum is the fastest known in the universe. The only way to surpass the speed of light is to use medium to slow down the speed of light. Although the speed of light was surpassed by cheating, the discovery of Cherenkov radiation gave us more information about cosmic particles and proved that the speed of light is not insurmountable.
Wormhole theory and warping drive theory can surpass the speed of light, but they can't be realized yet. Wormhole theory needs huge gravitational folding space, and it is difficult to keep the wormhole stable. It is a theoretical product that transcends four-dimensional time and space, and no artificial or natural wormholes have been found yet. Warp actuator is a compressed space, which needs huge "negative energy", which is also a theoretical product.
Maybe wormhole and warping drive can be realized in the future, but so far, the emergence of Cherenkov radiation is still the only practitioner who exceeds the speed of light.