You can immediately say that you will never buy a time machine in any store. You can go to the future at a speed close to the speed of 300,000 kilometers per second (at this speed, you will fly around the world several times in a moment). 300,000 kilometers per second is the speed of light. In addition, it is the ultimate speed that exists in nature. Interestingly, if an object moves at a speed close to the set speed, then time for it slows down.
Space, the speed of light and time travel
Physicists like to fantasize about two twins, one of which goes on an interstellar expedition on a photonic ship, and the second remains on Earth. This history is naturally carried to the distant future. This is how this story is told. Beth and Bob are twins. Both are thirty years old. Beth is an astronaut, Bob is a journalist. Beth receives a very responsible and long-term task: she is included in the crew of the first expedition to the nearest star. Bob will cover this flight in his newspaper.
Interesting fact: if, moving, you reach a speed close to the set speed, time for you will slow down your run.
A star and its planetary system are 96 trillion kilometers away from the Earth, or 10 light-years (light-year is the distance that light travels in one year, about 9.6 trillion kilometers). Ship Beth must fly at a speed of 90 percent of the speed of light.So, by earthly standards, a trip will take 22 years there and back. Over the years, journalist Bob got married, gained five pounds in weight, raised two children and turned gray.
Astronaut Beth, this time passed in a completely different way. While the ship Beth, in majestic silence, cut through the eternal blackness of outer space at tremendous speed, the onboard clock went slower than the clock on Earth. However, they did not have to fail. For astronauts, the course of time was unchanged, that is, the minute they perceived in a minute. Not the clock began to lag, but the real time itself began to flow more slowly for the ship and crew. No one on the ship felt any difference with Earth over time. The minute remained a minute, and by no means became an hour. Beth and other crew members more and more lagged behind earthly time, not noticing this at all.
After the flight was successfully completed, the crew sent a rocket to their native Earth. The onboard clock showed that 10 years have passed since they appeared after a long separation, they were terribly amazed. Beth had just turned 40, and Bob was 52. The twins are no longer alike. Bob calls space travel the source of youth and bitterly feels that he is hopelessly old.
Interesting fact: A light year is the distance that light travels in one year, about 9.6 trillion kilometers.
Beth is also at a loss: 22 years have passed, she returned to a completely unfamiliar world. She arrived in the future, looking 12 years ahead. The plots of this and similar stories are based on the conclusions of Albert Einstein's particular theory of relativity. This theory describes the laws by which motion acts on distance, time and mass.If the journey into space will take place at a speed even closer to the speed of light, then time for travelers will slow down even more, possibly for hundreds of years. Of course, the construction of such a high-speed rocket is a difficult technical task.
Time shifts
It was possible to register time shifts even at much lower speeds. The most accurate clock on board a supersonic aircraft lags by the smallest fraction of a second during the flight. But lagging behind! In his general theory of relativity, Einstein predicted that an increase in gravity also slows down the passage of time. There are science fiction writers who offer to send travelers to the past, using natural cosmic bodies with huge gravity - black holes.
