While Einstein's theory of relativity shows the relationship between time and speed. Theoretical ideas such as wormholes offer possible methods, but practical challenges and paradoxes, such as the "grandfather paradox", complicate the feasibility of time travel in practice
By Adi Ford, University of Maryland at Baltimore
Time travel, a perennial issue in the field of science fiction, remains a complex and unresolved concept in science. The second law of thermodynamics requires that time can only move forward, while Einstein's theory of relativity shows the relationship between time and speed. Theoretical ideas such as wormholes offer possible methods, but practical challenges and paradoxes, such as the "grandfather paradox", complicate the feasibility of time travel in practice.
Will time travel ever be possible?
Have you ever dreamed of traveling through time, like characters do in science fiction movies? For centuries, the idea of time travel has captured the imagination of many people. Time travel is the idea of moving between different points in time, just like you move between different places. In the movies, you may have seen characters use special machines, magical devices, or even a futuristic car - to travel back or forward in time.
But is this just a fun movie idea, or could it really happen?
The science behind time travel
The question of whether time is reversible remains one of the greatest unsolved questions in science. If the universe works according to Laws of thermodynamics, this may not be possible. The second law of thermodynamics states that things in the universe can stay the same or become more disordered over time.
It's a bit like saying you can't turn an omelette back into an egg. According to this law, the universe can never return to exactly what it was before. Time can only move forward, like a one-way street.
Time is relative
Yet, Einstein's special theory of relativity suggests that time passes at a different pace for different people. Someone speeding on a spaceship approaching the speed of light - a billion km/h - will experience time more slowly than a person on Earth.
Humans have not yet built spacecraft that can travel near the speed of light, but astronauts visiting the International Space Station circle the Earth at speeds approaching 17,500 km/h. Astronaut Scott Kelly spent 520 days on the International Space Station, and as a result aged a little slower than his twin brother – and fellow astronaut – Mark Kelly. Scott was 6 minutes younger than his twin brother. Now, because Scott was traveling much faster than Mark and for so many days, he 6 minutes and 5 milliseconds younger.
Time is not the same everywhere – Theoretical possibilities and challenges
Some scientists are exploring other ideas that could theoretically enable time travel. One concept involves wormholes, or hypothetical tunnels in space that could create shortcuts to travel across the universe. If someone could build a wormhole and then find a way to move one end close to the speed of light – like the hypothetical spacecraft mentioned above – the moving end would age more slowly than the stationary end. Whoever entered the moving end and exited the wormhole through the stationary end would have exited in the past.
However, wormholes remain theoretical: scientists have yet to identify such a hole. It would also be very challenging to send humans through a wormhole tunnel in space.
Paradoxes and failed dinners
There are also paradoxes associated with time travel. "The grandfather paradox” The famous one is a hypothetical problem that could arise if someone traveled back in time and accidentally prevented their grandparents from meeting. This would create a paradox where you were never born, which begs the question: how could you travel back in time in the first place? This is an amazing puzzle that adds to the mystery of time travel.
Stephen Hawking explored the possibility of time travel by Organizing a celebratory dinner where orders specifying the date, time and coordinates were sent only after this happened. His hope was that his invitation would be read by someone living in the future, who had the ability to travel back in time. But no one came.
as he is Please specify: "The best evidence we have that time travel is not possible, and never will be, is that we have not been invaded by hordes of tourists from the future."
Telescopes are time machines
It is interesting to note that astrophysicists armed with powerful telescopes have a unique form of time travel. When they peer into the vastness of the cosmos, they are looking into the primordial universe. Light from all galaxies and stars takes time to travel, and these light beams carry information from the distant past. When astrophysicists view a star or galaxy through a telescope, they do not see it as it is now, but as it existed when light began its journey to Earth millions to billions of years ago.
Telescopes are a kind of time machine - they allow you to peek into the past.
NASA's newest space telescope, James Webb Space Telescope, peering at galaxies which were created at the very beginning of the big bang, about 13.7 billion years ago.
While it's unlikely we'll have time machines like the ones in the movies anytime soon, scientists are actively exploring new ideas. But for now, we'll have to enjoy the idea of time travel in our favorite books, movies and dreams.
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More of the topic in Hayadan:
7 תגובות
"Time" does not exist as a physical entity. There is no way to detect time directly. An analog clock measures movement. A digital clock measures change.
What exists in reality is change. Every change in reality has another characteristic that identifies it. Change in place - movement. There may be a change in color, weight, etc.
A change without an additional property is an abstract change. It is a mental creation. Abstract change is time!
That is why it is impossible to "travel" in time because there is nothing to travel to.
Now you have to define what is past, present and future if time does not exist.
present exists. The present is existence, this is reality, this is being. This is the experience.
The past does not exist. The past is in a memory component that exists in the present. He didn't "was" either. It exists in memory space in the present.
Future, probably exists only in human imagination or maybe also of animals. He does not exist in silence.
The past is in memory, the present in experience, and the future in imagination...
How long did it take for human culture to answer the question,,, what is time?
What is this painting? The answer is simple - it is a painting with a unique shape.
And what is this painting? The answer is simple - it is a painting with a unique shape.
And what is this painting? The answer is simple - it is a painting with a unique shape.
And what is this painting that is composed of the three previous paintings?
The answer is simple... it's a painting made up of the three previous paintings.
For thousands of years man has been messing with this painting of time, because people have asked a question that has no answer - and it is... what is this painting of time..
And why is this an unanswerable question?
Because the possible answer creates a vicious circle.
What is this painting?
Answer - this painting is this painting.
On the question... what is this painting from a time when many years of life were wasted, and never
No answer appeared to her.
Thousands of years have passed, and thousands of books have been written, and this painting remains a painting with a unique form, and that's all.
The answer appeared at the turn of the 19th century in neurophysics
This drawing from time is the name of a "continuous quantitative thing" and in short, DACr
It is impossible to identify a beginning and an end in a continuous quantitative thing, and any quantity we choose from it,
will always be between zero amount and infinite amount.
Continuous quantitative things appear in physical reality and there are only 5 of them.
Length, area, volume, time and energy.
Length is a centimeter, area is a centimeter, volume is a centimeter, time is a centimeter,
And energy is a doctor. It is these five dachars that create physical reality, and they are the ones that provide a completely new explanation of the structure of the universe.
These dachars create the exact sciences of geometry and physics.
These are the exact sciences, because their quantities are always between zero and infinite quantities. Therefore great precision is required to express such quantities.
Mathematics is a quantitative language suitable for students.
Expansion in the book
"The magic journey of Asbar on the wings of natural knowledge".
A. Asbar
"Someone speeding on a spaceship approaching the speed of light - a billion km/h - will experience time more slowly than a person on Earth" is a wrong wording. The traveler will not *experience* any change in terms of time in his reference system.
The description of jumping through time using a wormhole is also wrong. As far as I know there is no need to "move" the end of the hole at high speed to achieve the effect.
As noted in the article, there is no problem traveling *forward* in time (that's what astronaut Scott Kelly did), but traveling backwards is problematic for the reasons noted, mainly the grandfather paradox and such. It's just a shame that it wasn't explicitly stated in the body of the article.
Apparently these problems already appear in the original article (I didn't check)
"Someone speeding on a spaceship approaching the speed of light - a billion kilometers per hour - will experience time more slowly than a person on Earth." - This must have been the wording in the original as well, but it is a very bad wording. He *will* experience time just like the one who remained on the earth.
Be upset, if you don't return in time to peace, you will lose the bed by the window, isn't it haram?
The active time trap
Active time (the one that disappears as soon as you think about it) cannot be measured.
Active time is not in physical reality, and has always been
In people's heads, and in their deepest consciousness.
Therefore, the length of a line is measurable, and the length of active time is not.
Measuring active time has no physical meaning, and the measuring device called a clock has no physical meaning.
The amount of time between two ticks of a clock has no physical meaning.
And in reality there is no fixed standard for active time.
Therefore, there is no physical meaning to the moment of the big bang that occurred many years ago
There is also no physical meaning to a moment from the past, and there is no physical meaning to a moment from the future. Nor does a mere moment of active time have any physical meaning.
You said a moment - he has already run away and disappeared, but psychologically he exists.
Active time does not exist in physical reality, and it exists only in the heads of human beings, or in their deepest consciousness.
Active time is man's greatest invention, which helps every human society to function in physical reality, but this time is not in physical reality, but it is in human consciousness.
The greatest human ideas have always been beyond tangible reality.
What exists in physical reality is a certain type of time unknown to science, called passive time, and it appears in the book
"The magic journey of Asbar on the wings of natural knowledge".
Passive time is the real time, and together with the energy they create the substance.
Thus begins a new physics that shatters conventions of thousands of years, and it
Neurophysics.
A. Asbar
time travel
There is no doubt that time travel is possible.
Such a journey can be made by any person, who will become completely rested.
The natural state of man is a state of movement.
Man lives on the earth and the earth is always moving. And even if man floats in space, he is also in a state of motion, like every star in space.
The ever-moving man cannot travel through time.
In order to travel through time, man must change his natural state, and become completely relaxed. The only way that allows a person to be completely relaxed, requires the use of his unlimited imagination and natural knowledge.
A completely rested person knows that he is in his place, like the passive time.
Passive time is absolute rest and absolute cold, and it fills the infinite space.
The infinite space is not empty, and is full of passive time.
In any direction we measure passive time, we will find 0.0033 microseconds per meter.
Passive time is the only physical thing that bears the title of absolute rest.
The stars of the universe move through passive time each in its absolute motion, and only
A person at absolute rest sees absolute movements of stars, which are in a spiral shape.
The stars do not move in a straight line path, nor do they move in a closed circular path. The stars move in the form of a helical orbit, characterized by diameter and angle of advancement.
The spiral shape of the orbit of the stars is seen only by a completely relaxed observer.
The person in his natural state of movement sees only the relative movements of the stars, and does not see their absolute true movements.
Only a completely relaxed person will see in his imagination the real movements of the stars, and will also see in his imagination the entire universe.
The universe is a finite collection of stars that looks like a disk, and this disk is forever moving in a straight line in a certain direction, at a speed of 12 times the speed of light.
The real man, who is always moving, does not see the real structure of the universe,
After this wonderful journey in time, he already knows the passive time that it is
fills the infinite space, and is the medium in which passive time waves move, transmitting the sunlight.
After this wonderful journey, the real person knows that there are two types of time, the passive time that always rests, and the active time that exists only in the person's imagination.
Active time does not exist at all in physical reality, and it exists only in man's imagination. What exists in physical reality is passive time.
And what turns out? , that time travel does not require active time at all
The time traveler comes to his miraculous knowledge at the same moment that the time travel began.
The idea of the two types of time, the active and the passive, first appeared in neurophysics at the end of the 19th century
Since the days of ancient Greece, until today, physicists only dealt with the active time
which does not exist in physical reality, but only in man's imagination.
The neural revolutionary physics, as well as the neural revolutionary geometry that offers science the scope experiment, are met with enormous resistance due to the innovations.
A. Asbar