In my book Breaking the Free Will Illusion, I have a chapter titled “Quantum Misunderstandings and Contrivances”. In it I touch upon the fact that in quantum mechanics (which addresses the smallest particles and their behavior) there are numerous “interpretations” surrounding what certain experiments show, and surrounding the mathematics used to describe this scale. These interpretations are rightly called “quantum interpretations”, and they compete with each other. Some are deterministic (meaning entirely causal), others are indeterministic (meaning some events don’t have causes), and others are agnostic on whether all events have a cause or not.
The fact of the matter is, we just don’t know which interpretation is the best model of reality. They each have their unintuitive problems. Regardless of this, I delve into why none of them can help grant free will.
One of these interpretations, however, is so un-evidentary that it really can’t be taken too seriously. Yet I’ve come across many occasion when someone will invoke this interpretation as a savior of free will. The interpretation I’m talking about is called the many-worlds interpretation (also known as many-universes or many-histories interpretation). Though all of the interpretations are speculative, this interpretation speculates on “worlds” that are impossible to prove. A huge no-no in science. But worse than that, not only does it not grant free will, but out of all of the processes it is the most fatalistic.
As the interpretation goes, for each possible state that a particle can be in, such leads to different histories, worlds, or universes. All of these “possibilities” exist (in what’s called a superpositioned state), but only one comes to the forefront of each universe through a process called “decoherence”. This means there is practically an infinite number of universes, as each moment and each event diverges into many many universes. In one universe you may have shaved off your eyebrows, in another, you may have cut off an ear with that same razor. Everything that theoretically “could” happen, does.
The first thing to note is that this interpretation is a deterministic interpretation. That’s right, if you think invoking it escapes determinism, you are better off with a different interpretation such as the Copenhagen interpretation (where some events don’t necessarily have a cause).
But there is no many worlds interpretation that’s indeterministic. Also, the word “possibilities” is really convoluted when used in the sense of this interpretation. Here’s a short blurb from my book to understand why:
First, for one superpositioned state to decohere to a specific universe over another superpositioned state, that implies causal variables that need to be there that push it to such perceived section of the environment (for “decoherence” it is coupled with a specific environment in this interpretation). And likewise, the other superpositioned states would each need their own causal variables to decohere to the forefront of their own environments.
But if this were the case, then only one would be a possibility for that particular environment, and hence suggesting the others as “possibilities” would be quite an inaccurate description. Rather, each superpositioned state would, by necessity, need to decohere into the specific “universe” or environment it does, due to the causes being different for each superpositioned state.
It falls into the problem we addressed with a cause not being able to have multiple possible opposing effects. If we were to say that the superpositioned states were actual different possibilities that would come out from a prior event, the only way for such multiple possibilities is if we have an acausal event. But then we run into the problems acausality would pose in regards to existing “superpositioned” states. If they are causal, only one would be a possibility for a specific environment, so saying the other superpositioned states are “possibilities” would be incorrect. If they existed, they would have to happen within the environment they were causally coupled to “decohere” into.
So no, not only is this interpretation entirely causal, but the word “possibility” isn’t very helpful given that they are in actuality the only possibility for the very specific environment they are coupled to. Each event decoheres into the universe that it causally must. If you look up this interpretation for yourself, you will see that it’s a deterministic model. And of course free will is entirely incompatible with such determinism (not that it’s not equally incompatible with indeterminism).
But that’s not the biggest problem. If such an interpretation happens to be true (which again, we have no good reason to think it is), the way we lack free will turns into a bad way. With typical determinism, we can causally align with a better world. Our conscious thought is part of the process. With the many worlds interpretation, this is the case as well – for one universe. But what we do in one, another thing will be done in another. And in yet another, something entirely different. All of the possibilities happen. The best case scenarios happen, and the worst case scenarios happen. Some universes will maximize suffering to an extra-ordinary amount, others will have happy people skipping about. And every scenario in between will play out. If you happen to have the causality to be happy, rest assured your very state assures there is a different instance of you which can’t have that same state. Since you have the state you are in, the other worlds can’t contain the same possibility. You in fact have taken such option away from those other worlds by luckily being in the environment you happen to be in. Rest assured that there will be an instance of you starving, or who has had three failed suicide attempts.
In other words, this interpretation renders everything we do pretty much moot. Understanding that we don’t have free will is a good thing, but not if it’s due to fatalistic or defeatist assessments of reality. This is why the distinction between determinism and fatalism are important distinctions. For fatalism, what happens in the future does so regardless of our causal consciousness…rendering every conscious act we do pointless. Determinism by itself doesn’t, however, do that – it’s a good thing that creates consistency (e.g. of thought). A deterministic many-worlds interpretation, in which everything will happen anyway in some other universe, on the other hand, does lead to a defeatest output. And I’d suggest the postulation of these universes is as dogmatic as the postulation of being fated regardless of cause.
But don’t worry, no matter what mathematical model of a many-wolds interpretation is consistent, such could never give evidence of such universes actually “existing”. And that’s not to mention the large number of philosophical problems the interpretation must contend with that I haven’t depicted in this article (perhaps a later one). If one is to take a realist interpretation of such universes/environments existing, such will always and forever fall into the realm of science fiction.
Just be careful not to use such to attempt to validate free will, as you’d be barking up the wrong universe.