Time was and remains one of the greatest mysteries for philosophers and physicists. A block universe model could explain what we see in the universe and why we perceive time the way we perceive it.
You are born somewhere in space-time. You die, again, in space-time. Every moment of life passes somewhere in space-time. In short, this is the block universe model.
According to the so-called block universe theory, the universe is a giant block in which everything happens that ever and anywhere could happen. That is, the past, present and future exist simultaneously and are absolutely real.
How is this possible
The block has four dimensions: three spatial dimensions - for example, length, height and width - and a fourth, temporal dimension, or simply time. This is easier to visualize if you draw the block model of the world as a three-dimensional rectangle, or cuboid.
A block universe that contains everything that ever happened and will happen at any time and any place / ABC Science.
The two dimensions of this cuboid - for example, height and width - represent the three spatial dimensions of the universe. The third spatial dimension in the diagram above is not taken into account - the length of the cuboid - let it be time. A Big Bang occurs at one edge of the cuboid. The other has the very last moment of our universe. Let's call it heat death.
Promotional video:
The cuboid is filled with every event that ever happened. The location of events within a cuboid represents their location in spacetime. All events, including your birth and death, as well as this very moment when you are reading our article, exist somewhere in this block.
In a block universe, time stands still
Sometimes it seems that “today” is the present, “yesterday” is the past, and “tomorrow” is the future. Also sometimes there is an impression that the present moment is changing - tomorrow it will seem that “tomorrow” is the present, and “yesterday” it seemed that yesterday was the present!
From our point of view, time passes or passes. But in the block universe model, time doesn't go anywhere. In other words, there is no specific present moment in the block universe, and the moments of "past" and "future" are relative.
Consider the idea of “here”. I'm here. As you read this article, you might say to yourself, "I am here." Despite the fact that your “here” is different from the “here” of the other person.
Within the framework of the block universe model, talking about "present" or "now" is the same as talking about "here."
Suppose last week you made an appointment with a friend to meet at the nearest coffee shop and have a chat over a cup of great cappuccino, but your friend was late, and when he arrived, you said to him: "You are finally here!" At the same time, for example, once upon a time, Caesar may have said to himself: "Now I am crossing the Rubicon."
Both of these statements are correct. This is because talking about the present - or "now" - about the place in time in which you find yourself. Since we are always somewhere, everyone is in the present, as well as in the place that is called "here."
According to the block universe point of view, time or temporal relationships "earlier than" or "later than" exist. They are valid regardless of someone's location.
For example, the dinosaur Art is earlier than the dog Bobik. This relationship between Art and Bobik is true whether we are earlier than Art or later than Bobik.
With all of the above in mind, it is quite realistic to imagine how the idea of the past and the future can be understood. Just as "now" in this model defines the time at which the object is located, "past" means any time located before this point, and "future" refers to all times or events located after the location of the object.
So we can travel in time?
If time is just another dimension similar to space, does that mean we can travel in time?
In short, yes. But, of course, everything is much more complicated. Time travel is more difficult than space travel. This can be very difficult and expensive in terms of technology, so it cannot be said that it is available to us in practice. However, this is still possible - within the framework of the block universe model.
Wormholes, with the help of which you can move in space-time along the shortest path, are theoretically possible in the block universe / Discerning the Mystery.
We know that moving at a very high speed will slow down time so we can travel into the future. At a speed substantially close to the speed of light, one can tangibly move into the future. In addition, in theory, we know how to travel into the past. This can be done using wormholes - short paths through space-time.
So if you can travel in time, can you change the past? Not. This would create contradictions, and contradictions do not exist. In the block universe model, the past is no different from the future or the present.
Everything is relative: what is the past for you, for someone else is the future. So by going back in time, you are traveling to someone's future. This means that the past will not, in fact, be anything different from the present.
What happens if you travel back in time in a block universe? You will get out of the time machine and look around, take a walk. You will communicate with people and breathe air. Obviously this will have some effect on the time you arrive. You will trample a few ants, talk to people from that time, pet horses, feed donkeys, and so on.
You will behave in the past, in essence, the same as in the present. However, you will not change it. Just like eating a couple of sandwiches tomorrow morning instead of oatmeal, you will not change the past, but simply make it what it is: you do not change the past by traveling into it, but simply make it what it is and what it is. It was.
Confused?
Let's summarize. Whatever you do tomorrow, it just makes tomorrow what it is and what it always was. Whatever you do in the past, you make the past what it is and always was.
If you go back in time, you are part of it. But more importantly, you have always been a part of the past.
Events inside a block are always there: they do not change. So, as a time traveler, you don't just suddenly appear in the past. You were always in the past.
Whatever the time traveler does, it won't change anything inside the block. On the contrary, whatever the traveler does at any time makes that time and other times what they are.
Hence, we know that some of the things we have tried to do in the past have failed. We know that Hitler came to power in the 1930s, so we know that if we from the future, going back in time, try to prevent this event, nothing came of it.
Of course, the idea of a block universe is contradictory in itself. But for all the controversy surrounding it, it is considered one of the most promising approaches that can reconcile the cosmological understanding of time with our ordinary daily experiences. One thing is for sure: time is more than meets the eye.
Vladimir Guillen