Isn’t this a big open question in an already complex field in which
experts don’t really agree at all? how did he decided that MW is the
correct one?
u/mitchellporter22 pointsat 1612852716.000000
Because of quantum superposition, especially as manifested in quantum
interference (e.g. double slit experiment).
His argument is, that the choice is between an interpretation in
which superposition exists transiently, but then “collapses” into one
component of the superposition (this encompasses both “consciousness
causes collapse”, which is a common but IMHO mistaken reading of
Copenhagen interpretation, and various “objective collapse” theories
like GRW and Penrose’s OR); and an interpretation in which superposition
never collapses, and the appearance of collapse is due to the observer’s
location within one component of the superposition (i.e. Everett, many
worlds).
In other words, the argument is, that QM without collapse is simpler
than QM with collapse, so if the first option works, you should favor
it. In terms of equations, this is a choice between Schrodinger’s
equation, plus a collapse postulate, and just Schrodinger’s
equation.
Part of the debate over many worlds is whether the second option
actually works, e.g. whether one can obtain the Born rule (and
its more sophisticated counterparts), the part of quantum mechanics
which tells you the empirical probability of each possible outcome, just
from the Schrodinger equation.
Quantum superpositions aren’t just “dead + alive” … or let me say
“spin up + spin down”, which unlike dead vs alive does refer to a
property actually measured in quantum physics, the direction of the spin
of a particle… rather than being just “spin up + spin down”, quantum
superpositions are more like (for example) “3/5 spin up + i 4/5 spin
down”. When you apply the Born rule (probability is square of the
absolute value), the latter example gives probabilities of 36% spin up,
64% spin down. That is, if you repeatedly create something in that
superposition state, and then test to see if it’s spinning up or down,
on average it should be spin up 64% of the time, spin down 36% of the
time.
The question for many worlds is, how to justify this rather unobvious
interpretation of a superposition that is 3/5 “spin up” world and i 4/5
“spin down” world. Eliezer liked an argument due to Robin Hanson
(“mangled worlds”), but I think he regards this as a detail, and not
part of the basic argument in favor of many worlds.
He saw several groups of physicists having a legitimate debate about their field of expertise, and decided to insert himself in the middle, declare one side to be obviously wrong, and fart in everyone's face
It's worse than that. There's a lot of interpretations of QM, with some of them being developed in recent years. So Yud is not only saying that all the other "classic" interpretations are wrong, but he's also shutting down the possibility of new interpretations. Also, i like how this implies "Niels Bohr=wrong, Yud=right".
If you actually read the sequence, he refers to Solomonoff induction and Kolmogorov complexity something like a dozen times, alluding to them somehow indicating that MWI is true, without ever making a coherent argument how those would be relevant. Presumably the idea is that because MWI is "shorter" it should be more probable.
The way Solomonoff induction works is by considering a set of functions whose output begins with a string that matches your previous observations (the functions are then weighted by an exponent of negative length). You do not get to output probabilities; you have to make guesses. Copenhagen gives such a function: the collapse (which most physicists do not believe to be an actual physical process) gives you a guess. Many worlds, curiously enough, is not such a function; it is Copenhagen but missing the part where the output is made to match the required format. (As it is, it doesn't even produce probabilities).
So, if one was to actually look at the interpretations of quantum mechanics through the lens of complexity theory, some form of "collapse" is unavoidable. Induction is inherently subjective, it is not about explaining the world, it's about making guesses at what you see next. The MWI may one day explain to us how an apparent collapse happens, but a theory which actually matches what is observed has to include an apparent collapse because we can't directly observe the superposition, we observe one result or the other.
edit. Also, you can have very trivial laws of physics that would describe a large universe containing "you" inside of it. E.g. a 2^(10 ^ 300) * 10^100 sized 3D game of life universe, consisting of 10^100 sized blocks of cells, each block initialized with binary value of block's coordinate. The reason physics isn't this simple is that physics has to predict observations, not explain existence via spamming possibilities.
Chuds like Yud are naturally attracted to MW instead of something
like De Broglie–Bohm because rambling about pilot waves does not nearly
get yourself as much attention from other laymen as rambling about
parallel universes.
I feel like this is part of the reason. Talking about 'parallel realities' and such is far more interesting to the lay than talking about more boring interpretations such as Copenhagen.
Some kind of stupid misunderstanding of how formalized induction
works, I think (edit: note all his namedrops of Kolmogorov complexity
and Solomonoff induction when arguing for MWI). It is of course simpler
to produce an entire multiverse than to select a specific guess about
the world. He takes this “of course” and snorts it to get high off how
much people who studied this stuff are less smart than him.
However, formalized induction specifically requires that a prediction
of actual sensory input be made, and whether that’s gonna be simpler to
do by somehow pruning the multiverse or by maintaining some sort of
pointer, is anyone’s guess.
edit: and in any case the internals of shortest prediction functions
are not guaranteed to have any correspondence to the real world
anyway.
This also relates to other rationalist lore having to do with
proclaiming a god’s view of the universe and then arguing about where in
that universe you would find yourself to be; a question that makes a
great deal of unnecessary presuppositions comparing to the more basic
“I’m here, what is around me?”.
>"I'm here, what is around me?".
I have noticed that a lot of rationalists have issues with this, so it's easy to fill their heads with crazy shit and call it rationality.
I think the whole "postulate a world containing yourself" idea is broken. Boltzmann brain being an old counter example. Further weighting based on the number of copies only makes it even more broken.
Ironically for how much they namedrop Kolmogorov and Solomonoff, they never look a little more and see that nothing about those suggests you should (or even could) apply a number of copies weighting factor ala Bostrom / simulation argument / etc.
If a theory has to predict what you'll see next, then the number of copies is utterly unimpressive; if there's 1024 copies, then picking a specific one at random ought to take additional 10 bits.
The simulation stuff is the worst in that regard. As a hypothesis for “what is around me that would be consistent with what i seen so far” it is utterly absurd, consisting of nothing but excess complexity. It only works when you start by imagining a view from the outside, prejudicing yourself severely in favor of things that have an outside.
No I mean as in this version of “induction” is a formal construction in mathematics and physics which is distinguished from that discussed by Hume, speaking as a (very) minor expert on Hume
I was shitposting but thanks for reminding me of the other definition of induction. Learned about it for a programming class. Got any recs for Hume reading? Was just reading an entry on the brophilosopher blog and wouldn’t mind something more serious.
Through purely non-empirical means- he had a theory he liked more,
and so found an argument to “prove” it was right without any actual
empirical data. I get loving Many Worlds, it’s the most narratively
pleasing physics model, but that’s no excuse for violating the basic
procedures and rules of science.. That was the moment when I realized
Yudkowsky (and the Rationalists) were full of shit, and I turned against
them hard, and started actually reading the comments sections and
realizing how awful a lot of them got.
because any other interpretation would make it extremely, extremely,
extremely clear that he doesn’t know what the fuck he’s talking about.
MW interpretation sounds a lot like a chintzy science fiction story, the
only means he or his dumbshit followers have of understanding the
world
Because of quantum superposition, especially as manifested in quantum interference (e.g. double slit experiment).
His argument is, that the choice is between an interpretation in which superposition exists transiently, but then “collapses” into one component of the superposition (this encompasses both “consciousness causes collapse”, which is a common but IMHO mistaken reading of Copenhagen interpretation, and various “objective collapse” theories like GRW and Penrose’s OR); and an interpretation in which superposition never collapses, and the appearance of collapse is due to the observer’s location within one component of the superposition (i.e. Everett, many worlds).
In other words, the argument is, that QM without collapse is simpler than QM with collapse, so if the first option works, you should favor it. In terms of equations, this is a choice between Schrodinger’s equation, plus a collapse postulate, and just Schrodinger’s equation.
Part of the debate over many worlds is whether the second option actually works, e.g. whether one can obtain the Born rule (and its more sophisticated counterparts), the part of quantum mechanics which tells you the empirical probability of each possible outcome, just from the Schrodinger equation.
Quantum superpositions aren’t just “dead + alive” … or let me say “spin up + spin down”, which unlike dead vs alive does refer to a property actually measured in quantum physics, the direction of the spin of a particle… rather than being just “spin up + spin down”, quantum superpositions are more like (for example) “3/5 spin up + i 4/5 spin down”. When you apply the Born rule (probability is square of the absolute value), the latter example gives probabilities of 36% spin up, 64% spin down. That is, if you repeatedly create something in that superposition state, and then test to see if it’s spinning up or down, on average it should be spin up 64% of the time, spin down 36% of the time.
The question for many worlds is, how to justify this rather unobvious interpretation of a superposition that is 3/5 “spin up” world and i 4/5 “spin down” world. Eliezer liked an argument due to Robin Hanson (“mangled worlds”), but I think he regards this as a detail, and not part of the basic argument in favor of many worlds.
Chuds like Yud are naturally attracted to MW instead of something like De Broglie–Bohm because rambling about pilot waves does not nearly get yourself as much attention from other laymen as rambling about parallel universes.
Some kind of stupid misunderstanding of how formalized induction works, I think (edit: note all his namedrops of Kolmogorov complexity and Solomonoff induction when arguing for MWI). It is of course simpler to produce an entire multiverse than to select a specific guess about the world. He takes this “of course” and snorts it to get high off how much people who studied this stuff are less smart than him.
However, formalized induction specifically requires that a prediction of actual sensory input be made, and whether that’s gonna be simpler to do by somehow pruning the multiverse or by maintaining some sort of pointer, is anyone’s guess.
edit: and in any case the internals of shortest prediction functions are not guaranteed to have any correspondence to the real world anyway.
This also relates to other rationalist lore having to do with proclaiming a god’s view of the universe and then arguing about where in that universe you would find yourself to be; a question that makes a great deal of unnecessary presuppositions comparing to the more basic “I’m here, what is around me?”.
Through purely non-empirical means- he had a theory he liked more, and so found an argument to “prove” it was right without any actual empirical data. I get loving Many Worlds, it’s the most narratively pleasing physics model, but that’s no excuse for violating the basic procedures and rules of science.. That was the moment when I realized Yudkowsky (and the Rationalists) were full of shit, and I turned against them hard, and started actually reading the comments sections and realizing how awful a lot of them got.
because any other interpretation would make it extremely, extremely, extremely clear that he doesn’t know what the fuck he’s talking about. MW interpretation sounds a lot like a chintzy science fiction story, the only means he or his dumbshit followers have of understanding the world
He was swayed by David Deutch’s arguments.