[sciborg2]

Multiverse Theories Are Bad for Science

New books by a physicist and science journalist mount aggressive but ultimately unpersuasive defenses of multiverses

I am not a multiverse denier, any more than I am a God denier. Science cannot resolve the existence of either God or the multiverse, making agnosticism the only sensible position. I see some value in multiverse theories. Particularly when presented by a writer as gifted as Sean Carroll, they goad our imaginations and give us intimations of infinity. They make us feel really, really small—in a good way.

But I’m less entertained by multiverse theories than I once was, for a couple of reasons. First, science is in a slump, for reasons both internal and external. Science is ill-served when prominent thinkers tout ideas that can never be tested and hence are, sorry, unscientific. Moreover, at a time when our world, the real world, faces serious problems, dwelling on multiverses strikes me as escapism—akin to billionaires fantasizing about colonizing Mars. Shouldn’t scientists do something more productive with their time?

Maybe in another universe Carroll and Siegfried have convinced me to take multiverses seriously, but I doubt it.

[themerchant]

The queston I have for multi-verse proponents is where does the energy come from?

[H]

The queston I have for multi-verse proponents is where does the energy come from?

My very rough understanding (I am far from an expert of QM or any multiverse stuff) but from Carroll's "Many World" interpretation, the idea is that the whole multiverse isn't "duplicating" or "multiplying" or anything, it's simply branching, which means that there isn't more or less energy pre- or post-branching, it is simply just "bifuraced" or, as Carroll himself sometimes puts it, the Many Worlds are "slices" of a very, very "thick" universe (or meta-universe, if you want, Carroll doesn't call it that, I don't know what he would call the whole thing).  Apparently there is math to back this up, but it's Penrose-like stuff that I can't even fathom.

I think there might be a notion of that it is finite, in a way, but the number of possibly sustainable branches is something absurdly huge.

[themerchant]

The queston I have for multi-verse proponents is where does the energy come from?

My very rough understanding (I am far from an expert of QM or any multiverse stuff) but from Carroll's "Many World" interpretation, the idea is that the whole multiverse isn't "duplicating" or "multiplying" or anything, it's simply branching, which means that there isn't more or less energy pre- or post-branching, it is simply just "bifuraced" or, as Carroll himself sometimes puts it, the Many Worlds are "slices" of a very, very "thick" universe (or meta-universe, if you want, Carroll doesn't call it that, I don't know what he would call the whole thing).  Apparently there is math to back this up, but it's Penrose-like stuff that I can't even fathom.

I think there might be a notion of that it is finite, in a way, but the number of possibly sustainable branches is something absurdly huge.

that just means split into 2 "bifuraced" and if energy is conserved then it must travel from one branch to the other and you need a mechanism for it.

There's many things described by maths that don't conform to reality for example. Using Maths you can take an orange slice it into many pieces then construct it back to something the size of earth due to the infite splitting/divisibility rule or whatever it is called. Yet try and do this in world (i.e. in reality) and it won't work even though the maths said it would.

Feynman talks about it in one of his books, probably his autobiography about arguing about it with mathematicians at university.

All these theories and no experiments, science is about falsifiable results if you can't even experiment on your theories it's philosophy not science. All imo of course.

[sciborg2]

All these theories and no experiments, science is about falsifiable results if you can't even experiment on your theories it's philosophy not science. All imo of course.

I'd even say MWI is bad philosophy. I don't really get the appeal - if the desire is to have an interpretation that doesn't have consciousness there are plenty to choose from. Even Wheeler's It-from-Bit, Participatory Universe stuff wasn't necessarily advocating observers are conscious entities.

[Wilshire]

All these theories and no experiments, science is about falsifiable results if you can't even experiment on your theories it's philosophy not science. All imo of course.

Just for clarity, people agree on this, yeah? One isn't "doing science" if all they are doing is proposing un-falsifiable claims, right? There is some division between theoretical vs. experimental of course, but is there a point where theory is so far from being verifiable that it ceases to be scientific?

[sciborg2]

All these theories and no experiments, science is about falsifiable results if you can't even experiment on your theories it's philosophy not science. All imo of course.

Just for clarity, people agree on this, yeah? One isn't "doing science" if all they are doing is proposing un-falsifiable claims, right? There is some division between theoretical vs. experimental of course, but is there a point where theory is so far from being verifiable that it ceases to be scientific?

Honestly wrt to MWI this isn't clear. Carroll has argued MWI is falsifiable if one falsifies QM, but this to me seems like such obvious sleight of hand I wonder if he's got a better argument that's been misconstrued...

That said, there is an argument that logically MWI is the best choice, but I see this as nothing more than the kind of aesthetic preference that determines which option one selects wrt to the Hard Problem of Consciousness.

[H]

Well, I am not an expert by any stretch, so I am pretty sure I am not at all qualified to condense or summarize Carroll's position at all.

If you really want to dive down the rabbit hole, you can likely start here where I think Max Tegmark at least seems to try to present many possible options on multiverses.  How probable or plausible are they all?  No idea.  The answer, I think, is likely always that we need to know more about QM, probably.

[themerchant]

All these theories and no experiments, science is about falsifiable results if you can't even experiment on your theories it's philosophy not science. All imo of course.

Just for clarity, people agree on this, yeah? One isn't "doing science" if all they are doing is proposing un-falsifiable claims, right? There is some division between theoretical vs. experimental of course, but is there a point where theory is so far from being verifiable that it ceases to be scientific?

I'm paraphrasing a Feynman point in a lecture about science.

https://www.youtube.com/watch?v=LIxvQMhttq4

It's also basically what i was taught and also think, although i might just be indocrtrinated to think that. Who knows.