I have posted a few different articles about how the universe will end mainly because I think it is fascinating to think about. Trying to imagine the very end of existence really boggles my tiny brain and I love it. Currently, I am reading Parallel Worlds by Micho Kaku, and IT IS AWESOME, (review coming soon) and the below ideas I got from his book.
There are any number of theories as to what will happen at the end of our universe. The most popular are the big rip, the big crunch, and the big freeze. These three are the most popular as they are believed to be the most viable in they could actually occur. The first two are possible but I think that most physicist would agree that the big freeze is the most probable solution as to what will happen at the end of our universe.
The big freeze states that as time moves forward the stars in the universe will eventually burn out. They will begin to exhaust their nuclear fuel many millions and billions of years in the future. Eventually far in the future there will be no stars left as they will have all burned out. There will be some red dwarfs but eventually those too will burn out and the universe will be dark. Because the universe is still expanding, matter will be spread out infinitely (so long as the universe keeps expanding). Because of these two factors the universe will become very very cold, hence the name the big freeze. With no warmth from stars and matter being very far apart the universe will be inhospitable to life, or so we think.
At this point in the universe if there were any beings alive it would be some sort of a miracle. I was of the mindset that any creatures still alive would have infinite technology and be able to survive anything regardless of the end of the universe. Or in another scenario if they did possess this technology they would probably leave this universe for a more hospitable one, but for this argument let’s say that for whatever reason they did not leave or they do not possess this technology.
While having infinite technology is great, I am not sure if this technology, if it exists, can bend or break the laws of physics. This is a major caveat and I will explain shortly but let’s keep moving forward. So at the end of the universe these beings would and should have miraculous technology. As the temperature continues to drop across the universe it is plausible that they would either modify their flesh and blood bodies to adapt to the lower temperatures or eventually they would abandon them all together. This seems like a reasonable idea as metal and other materials are more durable than flesh and blood. But still eventually even these materials would begin to fail as the temperature in the universe nears Absolute Zero, which is the temperature when all atoms would stop moving. At this point regardless of what material the beings would be made out of they would probably die because of the Third Law of Thermodynamics. Let me explain (This is why everyone should read. Using words like Thermodynamics makes you sound really smart when you say it, but in reality it is a very simple idea.)
The Third Law of Thermodynamics states that no system can reach Absolute Zero, it can get very very close but it will never quite get there. The caveat I mentioned above has to do with this law. If there is a technology that could either break or bend this law then the beings would be fine, but for the most part I do not think the laws of physics can be bent or broken. So let’s assume that this technology does not and could not exist. Now, because Absolute Zero can never be reached atoms can still move, albeit very very slowly. With that being said, let’s assume that these beings have the technology to abandon any sort of physical body and have their consciousness live outside the body. I am not sure how this would work but let’s assume they are some sort of collection of thoughts and memories in a sort of gas cloud. This may sound strange but if you think about it all thoughts and what not can be broken down into the tiny individual atoms that provide the chemical response in your brain, making up a thought or a feeling. So if there was a way to get those out of physical body and have them maintained outside the body, theoretically, they should function the same as at their base they are just atoms and molecules.
Now enter the Third Law of Thermodynamics. At near Absolute Zero all atoms have very little movement, so if this is the case a being whose mind is outside its body could exist, as it would just be a collection of atoms, but thoughts would take thousands if not millions of years to process. Not only that but the “brain” would be spread out over a near infinite distance of the universe as it continues to expand. I know this sounds really bizarre but if you follow the logic it mostly makes sense.
But again the caveat is if there is a technology to break this law or at the very least skirt around it. Technically nothing can travel faster than the speed of light, however, a warp drive could make it possible to achieve such a feat. I am not talking about Star Trek here, I am talking about a sound theoretical principle. What is interesting about the warp drive is that it constricts the space in front of the ship and expands the space behind, but the fascinating thing is that because of the constriction of space it creates a sort of bubble that I think is outside space. So because of this no physical laws are broken and you achieve faster than light travel. It is known as a Alcubierre drive. Now, that is all well and good and theoretically it is possible but the important thing is that no laws of physics are broken. I do not know if a similar principle or idea can be extrapolated to circumventing the Third Law of Thermodynamics.
Another interesting point that was made in the book is that if this being did exist, and this is where the book kind of lost me, no new memories could be made. I guess if you think about it it makes sense, as there would be nothing going on. Atoms would almost cease to move, so almost every moment would look the exact same as the next. For all intents and purposes time will have appeared to stop. So the being would just be there in the nothingness reliving its past memories that take forever to process. Now the book states that even though the memories would take a long time to process this speed would seem normal to the individual, everything would be relative. I don’t know about you but that does not sound like a fun way to spend eternity, basically alone with your thoughts. The book did not state what it would be like if there were many beings alive during this time and how they would communicate. I would assume the Third Law of Thermodynamics would play a part as well. Again any communication would take a long time, but I wonder if that too would be relative and the beings would not notice.
This is a very interesting idea and something that did not cross my mind when thinking about the end of the universe. However, I do think that any being that would be alive at this time would have technology that we cannot even imagine. For that reason I think that they will have figured out a way to solve this issue much like the Alcubierre Drive circumvents the FTL travel problem. Who knows, perhaps a civilization sensing the end is near would simply leave for greener pastures so as to not have to deal with this problem. I think that both solutions are viable answers.