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Will time travel ever become a reality? – Alana C., 12, Queens, New York
Have you ever dreamed of time travel, like characters in science fiction movies? For centuries, the concept of time travel has captivated people’s imaginations. Time travel is the concept of traveling between different points in time, just like traveling between different locations. In movies, you may have seen characters use special machines, magical devices, or jump into futuristic cars to travel back or forward in time.
But is this just an interesting idea for a movie, or could it really become a reality?
The question of whether time is reversible remains one of the biggest unsolved questions in science.If the universe follows it laws of thermodynamics, it may not be possible. The second law of thermodynamics states that things in the universe can either stay the same or become more disordered over time.
That’s like saying you shouldn’t thaw an egg once it’s cooked. According to this law, the universe can never return exactly to its previous state. Time is like a one-way street; you can only move forward.
time is relative
However, physicist Albert Einstein special relativity This suggests that time passes at different rates for different people. Someone was approaching at great speed in a spaceship. speed of light – 671 million miles per hour! – You will experience time slower than any human on Earth.
Although no spacecraft has yet been built that can travel at near-light speeds, astronauts visiting the International Space Station orbit the Earth at speeds close to 17,500 miles per hour. Astronaut Scott Kelly spent 520 days aboard the International Space Station, resulting in him aging slightly slower than his twin brother and fellow astronaut Mark Kelly. Scott was once six minutes younger than his twin brother. Now, Scott was traveling much earlier than Mark, and it took many days. 6 minutes and 5 milliseconds younger.
Some scientists are exploring other ideas that could theoretically make time travel possible. One concept includes: wormhole, or a hypothetical tunnel in space that might create a shortcut to a journey across the universe. If someone could build a wormhole and figure out how to make one end move at speeds close to the speed of light, the moving end would move more slowly than the fixed end, like the hypothetical spaceship above. and will grow old. A person who enters the moving side, passes through the fixed side, and exits the wormhole will come out in the past.
However, wormholes are still theoretical, and scientists have yet to discover them.It looks like that’s the case incredibly challenging Send humans into a wormhole space tunnel.
Contradictions and failed dinner parties
There are also paradoxes associated with time travel. famous “Grandpa’s Paradox” is a hypothetical problem that could arise if someone travels back in time and accidentally prevents them from meeting their grandparents. This creates the paradox that you were never born, which begs the question, “How did you manage to travel back in time in the first place?” This is a mind-boggling puzzle that deepens the mysteries of time travel.
In a famous story, physicist Stephen Hawking tested the possibility of time travel by: throw a dinner party Invitations with dates, times, and coordinates were not sent out until after the event. His hope was that his invitation would be read by someone living in the future who has the ability to travel back in time. But no one showed up.
Ash It pointed out: “The best evidence that time travel is not possible and will never be possible is that we have not been invaded by hordes of tourists from the future.”
A telescope is a time machine
Interestingly, astrophysicists equipped with powerful telescopes have a unique form of time travel. As they gaze out into the vastness of space, they gaze into the past. Light from all galaxies and stars takes time to travel, and these rays carry information from the distant past. When astrophysicists look at stars and galaxies with telescopes, they don’t see them as they are today, but rather as they existed millions to billions of years ago when light began its journey to Earth. I look at it as if it were.
NASA’s newest space telescope, the James Webb Space Telescope, peers into galaxies that formed at the beginning of the Big Bang some 13.7 billion years ago.
Although a time machine like the one seen in the movie is unlikely to become a reality anytime soon, scientists are actively researching it and exploring new ideas. But for now, we’ll just have to entertain the idea of time travel in our favorite books, movies, and dreams.
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