The many-worlds interpretation of quantum mechanics suggests that you would never perceive your own death, because if you were to die in one reality, your consciousness would simply transfer to a different reality where you survive.
UnsplashCould parallel universes be real? Quantum immortality says yes.
Imagine you’re walking down the street, and a car swerves and hits you. You die. Yet, in another reality, you may narrowly avoid the collision. The theory of quantum immortality suggests that your consciousness would seamlessly shift — to the universe where you survived.
According to the many-worlds interpretation of quantum mechanics, consciousness exists in alternate realities. This suggests that you never experience death in the reality you inhabit, because you would survive in a different reality.
This mind-bending concept has sparked debates in both the scientific community and the curious public. So, could quantum immortality be real?
What Is Quantum Immortality? Inside Its Origins From Quantum Mechanics
The idea of quantum immortality emerged from the many-worlds interpretation (MWI) of quantum mechanics first proposed by American physicist Hugh Everett III in 1957. In his theory, Everett suggested that the universe constantly splits into multiple realities where all possible outcomes of a quantum event occur.
Let’s say you wanted to go shopping with your friends. Before making your decision to go to the mall, your reality exists in two states: going to the mall or not going to the mall. When you make the decision to grab your keys and head out, your reality splits from the one where you decided to stay home. Now imagine this occurring for every decision you’ve ever made. According to MWI, the world is made up of an endless number of parallel worlds.
This idea was famously demonstrated in a thought experiment known as “Schrödinger’s cat.” In this experiment, a person imagines a cat in a box that has been rigged with a device that has a 50 percent chance of killing the animal. According to quantum mechanics, a field of study that examines the nature of particles at a scale smaller or equivalent to an atom, until the person opens the box, the cat inside is both dead and alive.
Wikimedia Commons/CC BY-SA 3.0Illustration representing the Schrödinger’s Cat thought experiment. According to quantum mechanics, the cat is in a superposition, balancing between alive and dead until observed.
According to the Copenhagen interpretation (CI) of quantum theory, whichever state is not observed collapses, resulting in a single outcome. In the context of Schrödinger’s Cat, then, CI states that if someone opens the box and finds the cat dead, there is no alternate reality in which it is alive. However, according to MWI, there is.
This represents the paradoxical reality of quantum mechanics. In this field, researchers specifically apply these principles to the study of particles smaller than an atom. At the subatomic level, objects act as both small particles and energy waves, depending on if they are observed or not.
In quantum research, scientists acknowledge something called the “observer effect,” or the change in behavior of particles when observed. For example, in the famous double-slit experiment, scientist Thomas Young directed a light source at two slits on a plate. Behind the plate was a screen observed by the scientists. When the light particles were not observed upon firing, they exhibited wave-like behavior. However, when they were observed, they acted like particles. In quantum mechanics, the act of measurement disturbs quantum particles in a way that alters the outcome.
Wikimedia Commons/CC BY-SA 4.0Thomas Young, creator of the double slit experiment.
These foundations of quantum mechanics led to the birth of the quantum immortality theory.
How Quantum Immortality Works — In Theory
Imagine you wanted to play a game of Russian roulette with your friends. You load a revolver with just one bullet, spinning the cylinder so the bullet will fire at random. Then, when your turn comes around, you put the gun to your temple, cross your fingers, and pull the trigger.
In this situation, assuming that you spin the cylinder each time, your odds of dying are roughly 1 in 6. But according to the MWI theory of quantum immortality, you would only ever experience the outcomes in which you survive, meaning you would never perceive your own death if you were the unlucky roulette player.
Formally introduced by Euan Squires in 1986, the quantum immortality thought experiment postulates that consciousness can transcend universes, always landing in a universe where death has not occurred. So even if you were the unlucky soul to lose Russian roulette in one universe, your consciousness would simply pick up where it left off in another universe.
This is referred to as quantum immortality.
If you think about moments in your life when you could come close to death — a car wreck, illness, or accident — quantum immortality says that – in an alternate timeline – you did die, but your consciousness continued to a timeline where you survived, allowing you to read this article today.
Like particles that can exist in multiple places at once, so can your consciousness. When you observe your consciousness, you are observing it in a living state. After all, you cannot check whether you are conscious after death. However, that does not mean that you haven’t died in an alternate universe, making it possible to have lived and died countless times.
Theories Of The Infallible Consciousness
Serious Science/YouTubeMIT scientist Max Tegmark, creator of the quantum suicide theory.
In 1997, Massachusetts Institute of Technology (MIT) physicist Max Tegmark published a paper testing the multiple worlds interpretation. Building upon ideas from others, Tegmark explored the idea of “quantum suicide” in which a person could travel through dimensions to find a universe where they survived a fatal event.
The quantum suicide experiment is similar to Schrödinger’s cat, except with people. A human test subject would be shot with a “quantum gun,” a gun dependent two possible spins of a quantum particle, one of which fires a bullet, one of which doesn’t. If the experimenter survives, they have achieved “quantum immortality.”
In essence, someone could theoretically live forever.
However, there are issues with quantum suicide and quantum immortality, and even proponents of the theory like Max Tegmark acknowledge that the theory is more than likely not true.
Perhaps the biggest glaring issue with quantum immortality is its inability to reckon with physical decay and aging. After all, how long can a single person avoid fatal accidents or health complications until their bodies are no longer able to sustain themselves?
Additionally, it does not tackle the problem of slow death. Someone may die over the course of a few months or even years, losing consciousness gradually. This gradual loss of consciousness spells out a big problem for quantum immortality. Where would parts of your consciousness go, and could it potentially spread across multiple realities, fracturing one’s own sense of self?
“After all, dying isn’t a binary thing where you’re either dead or alive – rather, there’s a whole continuum of states of progressively decreasing self-awareness….I suspect that when I get old, my brain cells will gradually give out (indeed, that’s already started happening…) so that I keep feeling self-aware, but less and less so, the final ‘death’ being quite anti-climactic, sort of like when an amoeba croaks,” Max Tegmark remarked.
Lastly, the theory of quantum immortality is nearly impossible to prove. As the scientific community currently does not possess the capabilities to travel on a quantum level and “choose” the alternate paths that would allow consciousness to continue, it is impossible to prove the theory true or false.
For now, quantum immortality and quantum suicide remain thought-provoking concepts that invites us to reflect on what it means to be alive — and what other versions of life may be out there.
After reading about quantum immortality, dive into the Phantom Time Hypothesis, a theory that states we are actually living the 18th century because the Middle Ages were faked. Then, read about 11 of the smartest people to ever exist.
