Why does nothing happen in MWI?

[Demystifier]

I want to be the cat.

Then you may want to read this:
http://lanl.arxiv.org/abs/1406.3221 [Eur. J. Phys. 36 (2015) 045003]

 

[Demystifier]

The "onion" structure of AdS/CFT (my favorite) does seem to imply hidden dimension(s)

Note that we live in a world where gravity is directly experienced, while the onion structure and hidden dimension (according to the mentioned theory) exists only in the dual CFT theory without gravity.

 

[Jimster41]

Note that we live in a world where gravity is directly experienced, while the onion structure and hidden dimension (according to the mentioned theory) exists only in the dual CFT theory without gravity.

I think I understand. I do wonder what those onion people call the information that gives us gravity.

 

[Derek Potter]

Here is a counterexample from the classical world. Consider two human twins, one weighting 70 kg and another 80 kg. (The second one eats more, so weights more.) Is it reasonable to conclude that the second twin is therefore more probable than the first twin? And what does it even mean, especially from the point of view of the twins themselves?

Yes, but the fundamantal postulate of QM is that the state is a vector in Hilbert space, not a human twin, so all the theorems of vector spaces apply, in particular Gleason's. There is no a priori reason why probability should depend on amplitude without that postulate.
Agreed, though, that the self-probability is always unity. Which is why it doesn't matter that the bundle of worlds that you and I inhabit right now have such a small amplitude that there isn't a word for it. Our world is real "to us".

 

[maline]

Now I am asking you: Is it the fact that the overall stone contains the sculpture? And is it also the fact that the same overall stone contains the sculpture2? And do you get the analogy?

I'm afraid I don't see the analogy. The only reason I see that the stone does not contain sculptures is that sculptures are defined by their shape, and the shape of an object is defined by the boundary between the object & the surrounding medium. Is there some analogous requirement which, in MWI, should prevent us from experiencing reality the way we do? And if so, how would "considering" representations as separate objects help?

 

[bhobba]

Yes, but the fundamantal postulate of QM is that the state is a vector in Hilbert space

Not necessarily. But it is the fundamental axiom of MW.

Thanks
Bill

 

[Derek Potter]

I think I understand. I do wonder what those onion people call the information that gives us gravity.

In our language it would be "xrtlwqngfffd". In theirs they probably call it flavour. They probably enjoy hamburgers and gravity.

 

[Derek Potter]

Its this exponential dilution of energy - in any normal process we would say it quickly decays to zero - but not here. Its a bit too weird for me.

I may be able to help you there. MWI in the deWitt picture involves splitting the universe, but it is a terrible picture. Far better to regard the universe as behaving quite nicely, conservation of energy etc but getting more complicated and thus generating new worlds in the sense of outcome-observer entanglements. The fact that you live in a world which, as part of the whole is of so low an amplitude that the number hasn't even got a name is irrelevant - the only things that interact with bhobba are things in bhobba's world(s), thus justifying normalising your state from your PoV.

 

[Derek Potter]

I want to be the cat.

Good idea as long as it's a Schrödinger cat. Schrödinger's cat has a serious flaw. Cats have nine lives so a typical cat will be alive every time - at least until the eighth repeat and generally about 17 of them. This is a kind of superselection. As far as I know it only applies to cats and the |alive> state, though maybe Schrödinger's Toast always falls butter-side up for a similar reason.

 

[Derek Potter]

I'm afraid I don't see the analogy. The only reason I see that the stone does not contain sculptures is that sculptures are defined by their shape, and the shape of an object is defined by the boundary between the object & the surrounding medium. Is there some analogous requirement which, in MWI, should prevent us from experiencing reality the way we do? And if so, how would "considering" representations as separate objects help?

Not sure who's saying what, but in MWI (the sort that makes sense, MMWI) that is exactly what happens, the state contains this world and Harry Potter's world in equal measure except that internal inconsistencies in HP make it impossible to say anything intelligible about it.

 

[atyy]

Good idea as long as it's a Schrödinger cat. Schrödinger's cat has a serious flaw. Cats have nine lives so a typical cat will be alive every time - at least until the eighth repeat and generally about 17 of them. This is a kind of superselection. As far as I know it only applies to cats and the |alive> state, though maybe Schrödinger's Toast always falls butter-side up for a similar reason.

How about superposition?

 

[Derek Potter]

How about superposition?

Superselection trumps superposition.

 

[Dale]

Closed pending moderation.

Edit: this thread will remain closed. I encourage all participants to review the forum rules on philosophy and speculation.