The 10 theories of the end of the Universe - medical - 2023



There are so many questions about the Universe that remain to be answered that, the more we advance in its knowledge, the more overwhelmed we feel by its immensity and by its tendency to make us see that the Cosmos is an amazing and, at the same time, mysterious place.

We know that our Sun has 5,000 million years to live. When our star dies, the Earth will surely disappear, for when stars the size of the Sun approach the end of their life, they turn into red giants. Therefore, the Sun will end up becoming an immense sphere of plasma that will absorb us before cooling down.

A bleak future, yes. But when we disappear, the Universe will still have a long, long time to live. We know that it is 13.8 billion years old and that the most plausible theory of its formation is the Big Bang.

Now, when will the Universe die? Does it have an end? What is your destination? How will it happen? Science is still not very clear on this, but there are well-respected theories in the world of astronomy that try to answer these questions. And in today's article we will see them.

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Will the Universe die?

Science does not know exactly. We know that it has been expanding rapidly since the Big Bang, which occurred 13.8 billion years ago. All the energy and matter necessary for the formation of galaxies, stars, black holes, planets ... Everything in the Universe was born from this "great explosion".

Now, to venture to know what will happen millions of millions of years from now is to mix astronomy with philosophy. As we have commented, we know that the Sun will die in 5,000 million years and we will die with it.

But what will happen to the rest of the stars? Will the galaxies keep moving further and further apart from each other? Can it be expanded unlimitedly? Will your energy run out? Is it infinite or is it finite? Without a doubt, we are a long way from answering all these questions.

Anyway, the theories that we will see next have been formulated following predictions based on the mass and energy of the Universe (including the concepts of dark mass and energy), its density and its expansion rate.

The knowledge in thermodynamics and astronomy seems to indicate that, in effect, the Universe will die. Although this depends a lot on what we mean by "dying." What is clear is that no material system can expand unlimitedly, and if it did, there would come a time when the energy would be so low that there could be no reaction.

Therefore, we do not know how it will do it, but everything seems to indicate that the universe has its days numbered. Still, some of the theories suggest that the Universe is barely a child compared to all the millions upon millions of years left until its final destiny is reached. Others, on the other hand, tell us that we could be closer to the end than it seems.

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What hypotheses about the end of the Cosmos are more accepted?

Explosions, black holes absorbing everything, cooling, bouncing ... There are many theories about how the Universe will die. So let's start our journey to get to know all these theories in depth and in a simple way.

1. The Big Rip

One of the great mysteries of the Universe is its accelerated expansion. According to what we know about Physics and, especially, about gravity, the Universe should be expanding at a slower speed each time. And this is what was believed until, in 1998, it was discovered that it was doing it at a faster speed.

With the predictions of matter and energy visible in the Universe, this is impossible. Therefore, physicists raised the existence of an energy that we cannot measure and that is contrary to gravity, in the sense that it drives the separation between bodies. This form of energy, baptized as "dark energy" would be the cause of this accelerated expansion.

But what really matters is that this repulsion, which is winning over the force of gravity, and which makes the galaxies increasingly separated from each other, could bring about the end of the Universe.

The Big Rip theory says that, from here some 20 billion years, the dark energy will eventually cause the tearing of all the matter in the Universe. Galaxies, stars, planets, and even subatomic particles will not be able to hold together. Therefore, this theory says that due to accelerated expansion, there will come a time when matter will lose its gravitational cohesion and therefore everything will be torn apart, ending the Universe as we know it.

2. The Big Freeze

The Big Freeze Theory or "Thermal death" he continues to defend that the key to the end of the Universe is in this accelerated expansion, although he does not believe that dark energy causes the tearing of matter. What it does say is that if the galaxies become increasingly separated from each other, there will come a time when they will be so far from each other that not even light will be able to reach them.

Therefore, as the stars die and, due to the distances that separate them, there is no more matter to form new ones (from here 10 million million years no more will be formed), the stars of the Universe will go out one after another, until, reached a point within 100 million million years, there are no stars left in the Universe.

Therefore, the Universe will be a colder and colder place where all the stars will go out and, simply, nothing will happen. The universe will be a graveyard of dead stars. Without a doubt, a very sad picture.

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3. The Big Crunch

The Big Crunch is one of the most exciting theories about the end of the Universe. This theory says that the expansion of the Universe cannot happen indefinitely (as the previous two theories affirmed), but that there has to come a moment (from here trillions of years), the density of the Universe will be so low that the expansion will stop and a process of collapse on itself.

That is, all the matter in the Universe will begin to come together (to contract) until it reaches a point of infinite density, like what happens inside black holes. All matter that exists in an infinitely small point, destroying itself thus every trace of matter that has ever existed.

4. The Big Slurp

The Big Slurp is a theory that looks like something out of a science fiction movie but, according to the laws of quantum mechanics, is plausible. To understand it, we first have to make an act of faith and believe that there are universes parallel to our own.

This theory is based on the principles of Higgs' Boson, a subatomic particle discovered in 2012 that is responsible for the mass of all other particles. Well, according to quantum laws, the mass of this boson indicates that the vacuum (the places where there are no particles) in the Universe is unstable.

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This instability of the vacuum implies that this is not the lowest energy state (which is what it was believed to be), because, if it were, it would have to be stable. Hence it is said that it is actually a false vacuum and that it could collapse into the true lowest energy state.

This would cause not only that the protons of all matter were destabilized, but that all the physical laws of the Universe would change. And do you know the worst of all? That, technically, this it could happen at any moment. In other words, the "bubble" that is our Universe could explode anywhere in the Cosmos and at any time, expanding a chain reaction that would devour us all.

5. Cosmic uncertainty

The least wet theory. In fact, the cosmic uncertainty theory says that it is virtually impossible to predict what the end of the Universe will be like. Well, according to her, the other theories do not take into account that dark energy has "changed its behavior" since the Big Bang, so we cannot know if it will do so again in the future. In other words, cosmic uncertainty is a current that says that theories about the end of the Universe cannot (and never will be able to) be proven.

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6. Massification of black holes

Black holes are the heart of galaxies. Therefore, all matter in the Universe basically orbits around black holes. In this sense, this theory says that there will come a time when, inevitably, all stars, planets, asteroids and celestial bodies will pass through the event horizon of some black hole.

In other words, millions of millions of years from now, black holes, both those that arise from the death of the most massive stars and those from the centers of galaxies, they will devour all the matter of the Universe. There will come, then, a time when in the Cosmos there will only be black holes, which, taking into account that they evaporate when emitting Hawking radiation, will also end up disappearing.

Anyway, the disappearance of black holes would take time trillions of trillions of trillions of trillions of years to happen. But when it happened, in the Universe there would only be radiation, but no matter.

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7. The end of time

The theory of the end of time is a very complex idea and difficult to understand. According to the laws of quantum mechanics, it is theoretically possible that time, which is still a dimension, stops. That is, this theory says that, simply, there may come a certain moment in the history of the Universe (it is not known if this will happen tomorrow or in trillions of years) when matter stop moving forward in the fourth dimension what is time.

That is, the concept of the passage of time will be lost. All matter will remain frozen as if it were a photograph. Therefore, this theory says that the Universe will not die, but will simply stop. Time will not advance and, therefore, an end as such will not be reached.

8. The Multiverse

The Multiverse Theory defends the existence of infinite universes parallel to ours where the laws of physics are different and with which we can never communicate, since they extend over a space-time fabric different from ours. Therefore, the end of our Universe would not really be the end of “everything”, since there would be infinite cosmos that would continue to exist.

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9. The eternity of the Universe

This theory defends that the Universe has always existed and that it will always exist. That is to say, it affirms that the Universe is infinite, because no matter how much the stars go out, our space-time fabric will continue to be there. There is no way to turn space into “nothing”, so, no matter how much matter changes and disappears, the Cosmos will continue to be there, forever.

10. The Big Bounce

The Big Bounce is a theory that derives from the Big Crunch in which, like this one, it is argued that the end of the Universe happens due to a condensation of all matter in a singularity. But instead of saying that this would cause the entire mass to disappear, this theory claims that it could be a way of "Recycle it".

And it is that the Big Crunch opens the door that, in reality, the life of the Universe is a cycle of expansion and contraction and that the Big Bang and the Big Crunch repeat themselves periodically, without really having a certain beginning and end. Therefore, the Big Bounce or Big Bounce Theory, unites both theories, defending that the universe oscillates.

After this condensation, would expand again with a new Big Bang. In other words, the life cycle of the Universe would be like a breath: the Big Crunch would be the inhalation and the Big Bang, the exhalation.