There is a simple, physical, concrete explanation for quantum mechanics. It fully explains the results without any mystical voodoo about multiverses or consciousness.
It's a simple explanation, but simple ain't easy. Physicists know about this explanation; they don't care for it because they find it philosophically distasteful.
Hard things are often good for you though. As difficult as this explanation is to accept, it also tells us something important about how we our lives.
First, we need to talk about explanations of quantum mechanics. The math and science of QM are the make the most accurate and precise predictions ever, confirmed by the most accurate and precise predictions ever.
The math and science are beyond doubt. But QM experiments probe reality at such a basic level, the more pressing question is what does the math mean.
The path of a baseball thrown from a pitcher to a catcher can be described by an equation representing a curve. Anyone who throws a ball has to aim higher than their target, because gravity pulls the ball down while it's on its way to the plate. In this case, there's no question what the math means; it's literal.
This is the same calculus Issac Newton came up with, and it still works great, on one or two objects. More than two and calculations quickly grind to a halt.
Statistical mechanics is a different way to calculate. Imagine you had a map of every pitch ever thrown in a baseball game.
You'd know the chances of the ball ending up in any given place. Large chance in the strike zone, surrounded by larger areas of medium chance. Low chance in the areas outside the batter's box – once in a while, a wild pitch goes way off course, but that doesn't happen often. Likewise there'd be a very small chance of the ball ending up at first base.
None of this tells you anything about where the next pitch is going to end up. If they swap out the pitcher, you know the percentages change and the areas shift. But from the averages you can't say where the next pitch will go.
The math expresses this as uncertainty. All the explanations of QM try to map that uncertainty back to part of the real world.
The two mainstream explanations, Copenhagen and Many-worlds, try to map the uncertainty to unreality. That's where all the voodoo comes from: the cat which is both alive and dead – which, by the way, Schrodinger came up with to illustrate how he didn't believe Copenhagen.
Superdeterminism takes the uncertainty literally – it says the uncertainty in the math represents what we do not (and can never) know. The physical reality exists, the cat is either alive or dead, we just don't know until we look in the box.
But this has a difficult consequence. We don't know where the ball will end up after the next pitch, but it will end up somewhere. If the uncertainty only represents our lack of knowledge, then the pitch has already been thrown and caught. We just don't know the result yet.
Superdeteriminism says the future is as real as the present, and as unchangeable as the past. Meaning that what we think of as "free will" is really a form of uncertainty – what we choose tomorrow has already been decided, in the same way that where we find ourselves today depends on the choices we made yesterday. The choices have already been made, but we don't know about the results yet.
It's a simple explanation, but not an easy one.