The reason we don't see time travelers is actually because they are not in our timeline

If we make the space station in space into a ring and let it rotate, then the humans in it will also feel the "centrifugal force" to "push" themselves towards the outer wall of the space station

Earthquakes are a common natural phenomenon. On average, millions of earthquakes occur on Earth every year, except that most of them are so mild that they are largely imperceptible to humans.

Theoretically, life can take many different forms, such as silicon-based life, sulphur-based life, carbon-based life, amino-life, hydrogen-based life, etc. However, so far we only know that life exists on earth, and all known life, including us humans, is carbon-based.

The universe is so unimaginably large that even if humans were able to travel at infinitely close to the speed of light, they would not be able to penetrate its mysteries. Fortunately, the speed of light is not the speed limit of the universe, so it is entirely conceivable that in the distant future, humans may somehow be able to escape the shackles of the speed of light.

It has long been discovered in practice that the phenomenon of "gravitational time dilation" does exist

If mankind can master the method of extracting uranium from seawater in large quantities in the future, there will be enough uranium on the earth to last for tens of thousands of years, even hundreds of thousands of years!

In the macroscopic world, the solar system is a system of celestial bodies centred on the sun, in which the vast majority of mass is concentrated and the major planets orbit the sun, while in the microscopic world, an atom is a microscopic system centred on the nucleus of an atom, in which the vast majority of mass is concentrated and electrons orbit the nucleus.

The energy released by nuclear fusion is actually an important basis for stars to be able to maintain their stability

In 2013, CERN discovered the existence of the Higgs boson for the first time.