There’s perhaps no other conversation as intriguing as speculating about the end of our universe. The potential outcomes range from the plausible to the outrageous. There is no shortage of imagination and creativity as we evaluate the various suggestions.
While many scientists believe that the universe will indeed end one day, they do not agree precisely how such a thing will happen. The disturbing thing is that some of these outcomes are more than plausible; there is a scientific rationale for supporting them. Here are the six (6) most legitimate ways that our universe could perish.
Death by Black Hole
Popular theories today believe that the majority of the universe’s matter is in the orbit of black holes. We know that galaxies contain most all things in the universe, and supermassive black holes lie at their centers. Blackhole theories include not only the direct cannibalization of stars. They also include the cannibalization of entire galaxies as they continue to get sucked into black hole event horizons.
If we have a finite universe, then black holes are going to gobble up most of this universal eventually, and only a dark universe will remain. Once in a while, a flash of light will be observed as objects get close enough to black holes to emit energy, but then things get dark again.
Over time, the sole thing remaining will be wells of gravity inside a considerable void. The most significant black holes will devour the smaller ones — making the big black holes even more massive. As this continues, black holes will ultimately evaporate and lose mass because they start emitting “Hawking radiation.” And when the final black hole evaporates, the only thing left will be Hawking radiation particles.
The Big Rip
This remarkable theory incorporates the unseen force known as “dark energy.” The premise of the Big Rip is that this dark energy is the driving force behind the rapid expansion that has been observed in the universe. As this expansion continues to accelerate, it will eventually rip outer space apart into nothingness.
Perhaps the most alarming feature of this theory is when it could happen. While most universe doomsday scenarios will occur well after the stars burn out, the Big Rip could happen within the next 16 billion years or so. During this particular phase in the life of the universe, it is believed that the planets and possibly life itself will still be in existence.
Therefore, this astronomical event could tear them apart or burn them alive — or whatever space dangers are lurking in between universes. This is anyone’s guess, but it is undoubtedly one of the most violent of universal deaths.
Vacuum Decay Event
In this disturbing event, a random bubble pops up somewhere within the universe. The laws of physics are extremely different within the walls of this bubble than they are outside of the bubble. As this bubble begins to expand at light speeds, it eventually displaces the entire universe.
As galaxies within the universe drift apart, atoms are no longer able to hold themselves together, and particles change the ways they interact. Whatever type of universe remains after this event. It will not be inhabitable for any kind of lifeform.
To comprehend vacuum decay, we must understand the vacuum state. Most of us see a vacuum as deep outer space and a place that is absent of matter. But outer space is never really empty as it is made up of quantum fields that fluctuate and create particles that support the fundamental laws of physics inside our universe.
These quantum fields are wheat holds reality together. When these underlying fields exist in their respective vacuum states, the universe remains stable. As dictated by the laws of physics, it is impossible for a system within a vacuum state to lose energy. If it ever did lose energy, that would mean that the laws of the universe have broken down and would cease to function any longer.
The Big Crunch
The most accepted theory regarding the birth of the universe is the Big Bang theory. This was the point that all matter had originally existed as a singularity — which was a single point of infinite density that resided in the nothingness of pre-universe existence.
An unknown factor causes the explosion of this single point. This group of infinite matter expanded in every direction at blinding speeds and created the universe that we observe today.
Conversely, the Big Crunch could be considered as an anti-Big Bang. As all matter continues expanding from the forces of the Big Bang, it is experiencing resistance from the gravity of the entire universe. Eventually, all this gravity will win out. The expansion will slow down and finally halt altogether.
At this point, we will see a contraction — much like how a rubber band would contract after it has been stretched to its breaking point. Only in this case, the universal contraction will pull back all that matter — including the material that has formed things like planets, galaxies, stars, and black holes — and it will keep pulling this matter until it once again reaches the center point of singularity.
The Inevitable Heat Death
The Inevitable Heat Death of the universe is a scenario where gravity was not strong enough to overcome the expansion of the Big Bang. Instead of becoming the Big Crunch, it will become the Inevitable Heat death because the expansion continues to grow exponentially, and galaxies drift further and further apart.
The universe is like the world around us; it follows the very same rules of thermodynamics. This means that any heat in the system will become evenly distributed. Common sense tells us that if our universe were to expand infinitely, the heat would also disperse, and temperatures will plummet.
All the stars will begin to die off, and there will be no energy to power up any new ones. The whole universe will become cold and dark. It will exist in a permanent state of equilibrium. While there will be particles, they will not be able to exchange any energy.
The Big Bounce
The Big Bounce is simply a more encouraging version of the Big Crunch. Consider how we described the Big Crunch earlier. Only this time, rather than all matter expanding from the Big Bang and then contracting back to the point of singularity, the Big Bounce hypothesizes that all matter bounces outward again into another Big Bang.
This theory had met with resistance from several physicists and scientists. The biggest issue pertains to whether or not the original point of singularity could be achieved. Many experts believe it is more likely that it will get very close and then get expanded again — which means it would create a new universe.
Notice how in this model, no matter is ever destroyed, it is merely recycled. In theory, the Big Bounce could be repetitive indefinitely, and we could actually be living in the 200th version of our universe.