Shouldn’t the default position be that a multiverse exist? A multiverse is what logic suggests (starting with “a point in motion is a line” and moving up to higher dimensions)
One thing I've wondered about is the assumption that every possible universe exists independently, with an infinity of entire universes splitting at every fork (n states per picosecond per particle, compounding!); it seems to me that shared state(s) and a long-tail of micro-diffs (like git / Merkle trees / etc) could model the same phenomenon more efficiently/parsimoniously (disclaimer: not even slightly a theoretical physicist). This could potentially allow sufficiently overlapping states to merge, or exactly opposing states to cancel, yielding an equilibrium amongst the sea of micro-probabilities, converging either to a singular universe, or a much smaller patchwork of stable universes (either separate, or intertwined).
This parsimony question also overlaps the Simulation Hypothesis: the fact that most physical laws resolve at macro-scale, by aggregating probabilities, and only break down into odd behavior (where a particle seems to care whether or not you're looking), smells to this programmer like an optimization hack. :)
Just started reading Donald Hoffman's "The Case Against Reality", which posits some very bold answers to this question, theorizing that there is no reason to assume that base reality is anything like our perceptions (subjective or scientific), any more than there's a reason to assume the perception of a desktop icon has a direct relationship with its filesystem implementation. The implications of a "consciousness-first" rather than "matter-first" explanation of existence are staggering, and it isn't hard to set up a model in which that explanation is more parsimonious than Multiple Worlds.
> what you're describing sounds more like a multi-dimensional (above the ones we're aware of) universe rather than a multiverse.
We’re aware of the possibility that we might do something, or could have done something. Does that count as an awareness of higher dimensions?
I don’t know enough about physics to understand how a multi-dimensional (above 4D) universe is different than a multiverse. I assumed they were one and the same concept.
>I don’t know enough about physics to understand how a multi-dimensional (above 4D) universe is different than a multiverse. I assumed they were one and the same concept.
Define 'multiverse'? Just so we're clear, the article is about the many-worlds interpretation of quantum mechanics. It's unclear to me that any given interpretation ought to be the anything; if anything, the Copenhagen interpretation is the orthodox one, and given that there's no conceivable experiment that could provably distinguish between the Copenhagen interpretation and the man-worlds interpretation, I would suggest that it has a better claim on being the 'default' one. (note: I am not stating that the Copenhagen interpretation ought to be the default one)
Science is just a tool to make predictions. We cannot test the multiverse theory, which leaves it in the realm of philosophy or religion.
This idea of a multiverse is some metaphysics sprinkled in with the Copenhagen interpretation that boils down to something like this: the total probability of any observed outcome summed with the probability of all possible outcomes is, of course, one.
The metaphysics is this-- assuming that all the outcomes that did not occur did occur in some other unobservable and inaccessible universes.
This is essentially the meaning of the plus symbol in summing probabilities; it separates the observed wavefunction from every other possible wavefunction.
It is absurd to draw such a mind-boggling conclusion from a plus sign.
To me science is more than a tool to make predictions - it's a way of trying to figure out what's going on using experiment, reason and the like. Maybe there are multiple universes or not and maybe we'll be able to test it or not. Who knows, reality is what it is.
That's called scientism, and its often conflated with science.
Just because a theory makes correct predictions, does not mean, necessarily that those mechanisms exist in the actual physical universe. It is entirely possible to make correct predictions with incorrect models.
Why isn’t the Schrödinger's cat thing sufficient? I don’t know much about quantum physics, but if we find situations where matter has odds of behaving a certain way, that seems like evidence. How do we explain events not always having a predictable outcome unless all possible outcomes occur somewhere?
This parsimony question also overlaps the Simulation Hypothesis: the fact that most physical laws resolve at macro-scale, by aggregating probabilities, and only break down into odd behavior (where a particle seems to care whether or not you're looking), smells to this programmer like an optimization hack. :)
Just started reading Donald Hoffman's "The Case Against Reality", which posits some very bold answers to this question, theorizing that there is no reason to assume that base reality is anything like our perceptions (subjective or scientific), any more than there's a reason to assume the perception of a desktop icon has a direct relationship with its filesystem implementation. The implications of a "consciousness-first" rather than "matter-first" explanation of existence are staggering, and it isn't hard to set up a model in which that explanation is more parsimonious than Multiple Worlds.