We have seen in this chapter that there are many ways in which the universe can be infinite in size and time, which suggests that everything that is possible must happen somewhere. We will now look at what that means for us all, personally. The idea has the name “quantum immortality”, because it was originally postulated based on the Many Worlds interpretation of Quantum Mechanics. But, it applies to all universes that are infinite (like the one you are in).
Let’s say that you die in your sleep tonight.
Let’s say it was because of something random, such as a sudden heart attack. Something painless that doesn’t wake you. You are simply alive during the day, and dead the next day.
Now, remember that there are infinite universes. Anything that is probable must be repeated in an infinite subset of those infinite universes. Your life up until now was probable. So probable, in fact, that it actually happened. Therefore, in an infinite number of universes, your life must be repeated, including everything that has ever happened to you, and every thought that ever occurred to you.
Those alternative yous are the exact same as you. If you were to swap places with one, you would not know, and no-one else would either.
Now, let’s say that there are yous that did not have a heart attack. “You” wake up the next day, not even knowing that “you” just escaped death.
The obvious thing to point out here is “yes, but that wasn’t this me – it was a different me”. Yes. But think of it this way:
1. “You” go to sleep
2. “You” wake up
There is literally no difference between the two copies of you that went to sleep. Right down to the thoughts, you are identical. So it should not surprise you to find that “you” wake up in the morning, no matter which “you” you were before you went to sleep.
Because the “you” that wakes up has thoughts, memories that are identical to both “you’s” that went to sleep, there is no difference between a person going to sleep and waking up, and a person going to sleep, dying, and then somehow “shifting” to another universe where they wake up.
I’m not at all saying that this is how it happens – you can’t shift between universes. What I’m saying is that it is identical.
You cannot experience your own death. The idea is nonsense – you cannot experience a universe where you do not exist.
So, it is logical that if it is at all possible for your thread of experience to continue, then it will.
Let’s consider another example. The classic example when it comes to Quantum Immortality is the idea of taking a six-chamber revolver, removing a bullet, spinning the barrel and then shooting yourself.
There is a 1 in 6 chance that you will spin to an empty chamber. There is a 5 in 6 chance that you will fire a bullet. So what happens?
Well, in 1/6th of all copies of the universe, you fire on an empty chamber and survive. In the others, you are dead.
1/6th of an infinite number of universes is still infinite.
Now you do it again. And again, you survive, because in most universes, you are dead, but the only ones that count to your personal identity are those where you survive.
Again, there are an infinite number of those universes.
Let’s say you put the missing bullet back in and fire again. What happens?
There are an infinite number of universes. There are an infinite number where you are dead. Is there a way for you to survive shooting yourself in the head with a gun?
Either you miss the brain and the bullet goes through the skin and out the other side of the head, or maybe you do actually shoot the brain, but not fatally, or maybe the gun jams, or maybe someone came to their senses and took the gun off you.
Don’t try to kill yourself. While Quantum Immortality says that you will live, it doesn’t say you will be in a good shape...