Is there a beginning or is the universe infinite?

The “Big Bang,” the Big Bang, is the common name for the theory of how the universe came to be. Researchers call this explosion the inflation phase.

Before that happened, the universe was a very compact mass that was very small. After the inflation phase, the universe continued to expand at a somewhat slower pace.

The big question is how can he go from nothing to a point of energy of a mass that has suddenly expanded at an extreme speed?

Either one or the other

That’s a good question, and no one has a satisfactory answer to it, says researcher Trygvi Leith Svalheim in the University of Oslo’s (UiO) Theoretical Astrophysics Department.

Philosophers have considered this phenomenon longer than physicists:

Either the universe is eternal, or it can be creation. It eventually became the dominant view, partly due to theological arguments, but just as much in a purely rational way, explains Professor Austin Linbow in the Department of Philosophy, History of Ideas, Art, and Classical Languages ​​at UiO.

Both philosophers and astrophysicists agree that it must be one or the other.

Physical evidence of the beginning

Sfalheim is working on a clue to the inflation stage. The theory states that the inflation stage would have resulted in gravitational waves, which should be able to find them. These are the early gravitational waves that Schwalheim is looking for.

– The evidence hasn’t been found yet, but those who found it secured a Nobel Prize in Stockholm, says Svalheim.

However, he is open to the fact that there are still several possibilities:

– Now it has been tested so well that the theory seems to be correct, but if it is not, we have to look elsewhere. Then there are variations in such cyclical universes that start with a Big Bang, expand, and then end in a phase with a new Big Bang in the future, he says.

If the universe were periodic, there would be an argument that there is some kind of eternity within the image.

The universe is an endless chain of events

The ancient Athenian philosophers were followers of the infinite universe. This reasoning is still valid in physics.

Aristotle, on the one hand, had an early form of the law of conservation in which you cannot take motion out of motion that does not exist. Every time you come back, there is always a previous movement that pushes the new movement into action. Lenibo explains that this would indicate that the universe should go on forever.

This is the only way philosophers have thought. These conservation laws apply in physics today as well.

On the other hand, there is a great deal of confusion in philosophy associated with this infinity. Many believe that infinity gives paradoxes, Lennebo continues.

If the universe were eternal, then time would be infinite. It gives paradoxes.

– and therefore we must conclude that it did not last forever and that it had a beginning, says the professor.

Infinity problem

The big problem with infinity is that a number of paradoxes emerge as a result of it.

Lenebo explains one of the paradoxes known as the Hilbert Hotel, first identified by the mathematician David Hilbert:

Imagine that there is a hotel with an infinite number of rooms. Each room is numbered and all rooms are booked. One day, another guest appears, but the hotel is full.

The receptionist gets a good idea: if the guest in room number one moves to room two, and the guest in room number two moves to room number three and so on, the first room becomes vacant.

– Then I made a new room with roaming guests. If you look at all the rooms and compare them to rooms number two and above, which of these groups are the largest? One is bigger, but they’re the same at the same time, so you get a discrepancy. Then Lenibo explains that there is something wrong with the starting point, i.e. infinity hotel is possible.

Boltzmann brains example

The Hilbert Hotel wasn’t the only paradox that emerged. Physicists have another paradox that is equally problematic.

In a vacuum, quantum fields will arise where things can happen and disappear from existence. It happens everywhere, all the time, according to Sfalheim.

“Given infinite time, at some point, such a structure of atoms will appear to look exactly like my brain, with all my memories and my awareness of exactly what I see now,” Schwalheim explains.

Then this brain will disappear, as suddenly as it arose. There is a greater probability of the emergence of such a brain, than that the whole universe will arise in this way.

With an unlimited amount of time, there will also be endless possibilities and different types of such minds. The result is that there is a greater chance that your experience of reality is not the real truth.

The physicist Ludwig Boltzmann was the first to outline this example, which is often called Boltzmann brains.

Strange consequences don’t mean that something is wrong

The example of Boltzmann’s brains shows how weird eternity is because all possibilities come true as long as the probability of their existence is higher than zero, says Lenebo.

However, Schwalheim thinks it’s not necessarily a problem anyway:

Theories that predict the existence of Boltzmann brains may be poorly defined. If such paradoxes work, we try to walk away, he says.

There is probably some change that you can make so that such paradoxes do not occur.

Linnebo pursues the fact that, after all, you must have a better theory before you can reject a theory because it has strange consequences.

“You have to consider if the consequences are just a big surprise that we have to get used to, or if there is something fundamentally wrong there,” he explains.

An example of a theory with peculiar results is quantum physics, which despite its properties is the best explanation for some phenomena in physics.

time before time

Time is defined by the second law of thermodynamics, which states that entropy always increases. That is, something goes from a state of order to chaos, and this time is the direction of that change.

– If you have a glass of water and you drop an ice cube into that glass, you will be able to go back and see that the ice cube has melted. If you photograph it and return it it will make no sense. It is a process that has only one direction. Svalheim explains that we’ve gone from a little mess to a much bigger mess.

The problem with time is that you need something to compare with to see that time has passed.

If you have nothing that can move or become a disturbance, you have in fact removed only the disturbing dimension of time, says Schwalheim.

Thus, such a way of looking at time leads to the time before the big bang is an orderly state in which nothing happens.

North Pole

– Before the Big Bang, there was no time, which is a bit satisfying for me. It’s like going north to the North Pole, and it doesn’t work, Schwalheim explains.

Over time, it is possible to imagine that all chaos will recover, and that there will be no more chaos to create. Then it is theoretically possible to imagine that time stops again, but according to Svalheim, the models for this are somewhat more complicated.

Researchers caution not to comment on whether there is an end.

If eternity becomes too paradoxical, one might imagine that there must be an end, but I will not guarantee it, says Lenibo.

It shows that there are mathematically consistent theories of sequences.

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