Problems with Many Worlds Interpretation

[Ken G]

or you rephrase (2) into a more empirist formulation like Ithink I did ealier in this thread that (2) is replaced by negotiated democratic observers and the laws of physics are not a constraint but rather a result of negotiation.

Or what may have a similar spirit-- we say that laws of physics are examples of whatever keys we can find under the streetlights.

 

[Fra]

we say that laws of physics are examples of whatever keys we can find under the streetlights.

Note sure if I got that metaphor.

To me the key here is interactions in between observers. Laws are somehow the consensus that observers can agree upon.

The difference is wether they HAVE to agree at all times, or wether the agreement is emergent. Before it has emerged, the state of law itself is dismissed into the same "black box" as is the system for which the theory was formulated.

What is the key for me is the democratic process or the negotiation, not possible equilibrium points for such process.

/Fredrik

 

[Eqblaauw]

Einstein has (in my eyes) a wonderful quote:
I don't believe in math, As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality
It doesn't in itself reject the mwi but I think it's a good medicine against some of the thinking of mwi-ers. It surely is a good medicine against 'mathematical universe' of tegmark, and of course all possible universes do exist, just like it is impossible that I ate a large apple pie this morning, the question scientists should be asking is which universe(s) are possible, and you don't do that by making some formulas that are consistent and saying: hey look at this, this is all possible.
Also, I don't imagine that the brightest mind in the world, that's for some reason death blind mute and only read (with his/her fingers) all the pure math books in the world, could ever come up with e = mc2

 

[Eqblaauw]

Tegmark says all consistent mathematically correct universes exist
to know if this has any meaning you can ask yourself the question: consistent with what?
-with itself
that really hasn't got any meaning at all, if it hasn't got any observation to verify it,
when there are observations, then you can see if it's consistent with the universe (or multiverse for that matter).
This mainly is against mathematical universes by the way.

R.I.P. Popper

 

[Eqblaauw]

poll update, (sorry to copy the earlier message with changes, but I somehow couldn't edit it) I asked the following question to eminent physics , none of which I knew their ideas in advance:

a: I subscribe to the MWI that contains many parallel universes that differentiate during every 'quantum event' (meaning that there are many perhaps an infinite number of copies of everyone that inhibits earth)

b: I subscribe to the MWI that contains many parallel universes that split during every 'quantum event' (meaning that there are many perhaps an infinite number of copies of everyone that inhibits Earth constantly being created)

c: I don't subscribe to a or b, because I think they are both false

d: I don't prefer any of the above

First some remarks
-2 said c/d, those where counted c 1/2, d1/2,
-one said I can't do anything with the poll, cause this has no empirical evidence and therefore has nothing to do with physics,
to avoid all accusations of being biased I didn't count him,
-one said c with a minor change, I don't subscribe to a or b,
to once again avoid all acusations of being biased I didn't count him in,
-one said I don't like both descriptions a or b, to me mwi just means unitary evolution but I chose b,
to avoid all accusations of being biased I did count him as b,
-one sais a,but with a very weak meaning of parallel meanings 'existing' (I don't really know what he means)
but once again to avoid being depicted as biased I counted him as a
-one didn't see a difference in a or b, but chose b because he thought the word 'split' was better (I now have added that in b you multiply as do universes, and c you already exist in many universes, but I think the description itself wasn't incredibly vague)
- one said d, He does however subscribe to the Everett relative state interpretation, and does think that all possible universes exist in 'some sense'
maybe some tiny percent of the (c's) or (d's) where subscribing to any mwi with parallel universes that wasn't mentioned in the poll,
But I think it's very unlikely (since I think the logical thing would be to make notice of that) These where the answers

C: 18
D: 7
A: 1
b: 2

the reactions came from (I promised to not make their names publicly, but since I don't mention who voted what, I don't think there is any harm in it):
David spergel, Carlo Rovelli, David polizer, David Finkelstein, Richard Muller, M.J. Rees, George F Smoot the Third, Goldreich, James Daniel Bjorken, Richter Burton, John Preskill, Leon N. Cooper, Robert Wald, James Binney, Yakir Aharanov, Andy Fabian, Ulrich Becker, Jim Al-Khalili, Frank Close, Frank Wilczek, Rodolfo Gambini, Jorge Pullin, John Baez. Donald Lynden-Bell, Rafael D. Sorkin, Mark Sredniki, Warren Siegel

the people that had extra comment and chose c said the following things:X1:

I think the many worlds interpretation is nonsence.
It does not survive Occham's Razor.

!me! when asked what his response was to mwi-ers answer <Occam's razor actually is a constraint on the complexity of physical theory, not on the number of universes. MWI is a simpler theory since it has fewer postulates> he said (I don't understand it, but I think some will) !me!

X1:
Any theory that predicts enormous numbers of copies of the universe
none of which are directly observable is introducing a huge
redundancy for explaining one small effect. That to me is quite wrong
and disobeys Occham's razor. It is easier to imagine that our concept
of a particle or a quantum are wrong in some way. There are already hints
of this from such matters as the spectra of diatomic molecules which
are radically affected by whether the nuclei are identical or not.
If as in Oxygen the nuclei are the same and of spin zero then every
other line in the rotational spectrum of the molecule is missing!
How does the molecule know its tiny nuclei are identical?

X2
Sure, my answer is definitely "c". I do not think that MW is good or
useful, in any variant.

X3
The many-worlds theory is a silly mistake, mistaking possibilities for actualities. It comes from the attempt to deny the statistical meaning of psi vectors
and regard them as real things, present in the individual system; and nevertheless to avoid the mistaken theory of "collapse" that such reification originally led to.
The theory that people actually use has one world, no collapse, transition probabilities, and incomplete descriptions.

X4
NO TO MWI

X5
My best answer is c. The theory is false because it is inconsistent.
a c/d vote said he considered it a argumentum absurdum, that we lack knowledge and he would have voted c if it not contained the phrase 'both false'

one d said: If a parallel universe is unobservable even in principle, then it's meaningless, according to established scientific method.
"Meaningless" means it's neither true nor false, since it's untestable

 

[Ken G]

Note sure if I got that metaphor.

The idea that the laws should be the same for all observers is not a law, it is a standard for laws. It is instructions for where to look for them, which makes them easier to find-- like a streetlight. It also says to look for laws that have a particularly "democratic" element, and to not consider as a law anything less. Note it is not falsifiable, so it is not itself a law.

Now wait, you say, of course relativity is falsifiable. But that's just any particular brand of relativity, like c being constant. Saying that the laws must be the same for all observers just means that if they only work for a subset, look for different laws that are the same for all-- that isn't falsiable. Physics went 2 centuries being content with laws that only work for inertial observers (it's obvious that F=ma is only a law for them), so it's a rather new standard, and we only adopt it because Einstein showed us we could. Einstein "found the keys in the streetlight", and asserted that we should always look for them there because it is easier to find them when you know where to look, and they are the kind of keys we are looking for.

To me the key here is interactions in between observers. Laws are somehow the consensus that observers can agree upon.

Yes, I agree this is the key. There would be no such thing as laws without observers, that's the part that rationalists don't like, and it's what MWI must reject.

What is the key for me is the democratic process or the negotiation, not possible equilibrium points for such process.

The road rather than the destination? Certainly sounds like an apt metaphor for science.

 

[Eqblaauw]

Dear mwi-forum participants,
the poll is closed, I've deleted my account, and there by any direct evidence of the poll, though everything I mentioned can be verified by the people mentioned,
if you want to use this poll for wikipedia or other sources you're free to do that,
I will vouch for that this poll is fully honest, and I also vouch for the statement david raubs poll most likely isn't.
I conducted the poll under the name 'Gertjan Kouweheuve' because I didn't wanted that any of my posts elsewhere would influence the poll. That's the only lie I permitted myself to, with this poll.
This also will be, if I can resist to login somehow, the last post I'm going to submit on this forum (physicsworld).
and as we say in some parts of holland 'houdoe!
Edo Blaauw

 

[nazarbaz]

Not necessarily. We don't have to choose between either saying that there is no "progress" in science, or that the ultimate goal is a "TOE." I don't think either of those views have much of a clue about the progress of science as it has been, and I don't see any reason to expect the progress of science to change suddenly now. Instead, I'd say these lessons of the history of science are pretty hard to deny:
1) scientific progress looks like gradually improving accuracy achieved by radically different ontological pictures, and
2) every generation thinks their own ontological picture is "on the right track", regardless of how completely it differs from previous ontological pictures.
Given these two seemingly uncontroversial facts, I think we can conclude that scientific accuracy converges, but scientific ontology does not. The main problem with postmodernist science is that it is generally not done by scientists, but it does have some useful "cautionary" remarks to make, as you say.

If we assume that scientific progress does exist, we must infer that our actual theories are effectively closer to the right picture than the previous ones (how close is a different question). In the history of science, there is both nicks and continuities.
The continuity is not an inner quality of the scientific effort, it's always super-imposed by rationalizations. The sociology and the factual development of science is misleading in that respect. We need to do the job and never expect to find it ready to use.

 

[Ken G]

If we assume that scientific progress does exist, we must infer that our actual theories are effectively closer to the right picture than the previous ones (how close is a different question).

Actually I would argue, as pertinent to MWI, that this is precisely what we can not infer. Making scientific progress does not require, and probably does not even suggest, that we are getting "closer to the right picture." I say this for three reasons:
1) scientific progress is always measured in terms of the increasing power it gives us over our environment and the increasing accuracy in our predictions, never by how right our picture is,
2) the pictures change so dramatically with each increment of accuracy and predictive power that no convergence of the "pictures" is in evidence, and there is also no direct connection between how much the picture changes and how much the accuracy improves,
3) there is no scientific evidence whatever that there is any such thing as "the right picture" that we could be moving "toward" in the first place.
These are important facts to bear in mind, because otherwise we fall victim to the same kinds of unjustifiable conclusions we turn up our noses at in pseudo-scientific endeavors.

 

[eqblaauw2]

If we assume that scientific progress does exist, we must infer that our actual theories are effectively closer to the right picture than the previous ones (how close is a different question). In the history of science, there is both nicks and continuities.
The continuity is not an inner quality of the scientific effort, it's always super-imposed by rationalizations. The sociology and the factual development of science is misleading in that respect. We need to do the job and never expect to find it ready to use.

I'm sorry but this must be one of the biggest pieces of crap I have ever read.
The newest theory (because at this moment I came up with it) is that the universe is a game played by Crocodile Harry, who has an Oedipuscomplex, and bad teeth.

I do however think a poll can indicate what the sciense community generally thinks at a certain moment, and that what the sciense community thinks generally is more correct then what the sciense community thinked in the past. However at this point the newer theory (MWI) isn't a populair theory at all (as I think I succesfully demonstraded). If and this is a big if, because I think if you do some reliable research you will find that there are other interpretations still more populair then MWI, MWI is the most popular theory that also doesn't mean it is a populair theory since the majority clearly rejects it. Then the most populair idea would be we don't know. But again this is an if, because the MWI theory isn't that populair at all (more populair then you would think at first notice when you read the rather extreme point of view, but still not close to being populair).

P.s. sorry that I couldn't resist login in again, but I really hate ********

 

[eqblaauw2]

I must say I quess the only positive thing of mwi for me is it really made me appreciate more my believe that everyone is unique, and that I'm mortal (if you really think about it being immortal is far more worse then being immortal, although that isn't nice either). And of course that I have made a reliable poll that may have helped people.

 

[BruceW]

However at this point the newer theory (MWI) isn't a populair theory at all (as I think I succesfully demonstraded). If and this is a big if, because I think if you do some reliable research you will find that there are other interpretations still more populair then MWI, MWI is the most popular theory that also doesn't mean it is a populair theory since the majority clearly rejects it. Then the most populair idea would be we don't know. But again this is an if, because the MWI theory isn't that populair at all (more populair then you would think at first notice when you read the rather extreme point of view, but still not close to being populair).

Many of the interpretations have several different possible meanings (MWI in particular). So a survey of the preferred interpretation is not very useful.
In most textbooks, CI is stated as the most standard interpretation, and in most situations CI is the easiest to understand. So for these reasons, I would guess CI is the most popular.

 

[Ken G]

The poll did refute claims that MWI has transitioned into the most popular interpretation, often cited as a consequence of better understanding of decoherence. I've tried to stress that this argument stems from an incorrect placing of "collapse" into opposition with "decoherence", when in fact the correct relationship is "decoherence sets the stage to interpreting collapse, whichever interpretation of collapse is used." CI works just fine in a "decoherence leads to collapse" framework, it was never one or the other.

Also, I still say that bashing interpretations is kind of silly, because all interpretations do is give us a new angle with which to look at our theory. We can bash the taking of an interpretation literally, to the point of using it to draw conclusions about how reality actually works, but that's not bashing the interpretation-- it's bashing what the interpretation is used to do. That's what I mean by creating a "world view" from MWI, and I think the history of science is all too clear on the pitfalls of doing that, even for interpretations not nearly as bizarre as MWI.

 

[eqblaauw2]

Many of the interpretations have several different possible meanings (MWI in particular). So a survey of the preferred interpretation is not very useful.
In most textbooks, CI is stated as the most standard interpretation, and in most situations CI is the easiest to understand. So for these reasons, I would guess CI is the most popular.

read the poll (it's on this forum), read it again if nessasary: it's offering a clear insight that probably the mwi's that are mostly advocated (including Bryce de Witt's, who really for the first time actually 'made' the mwi, and I think thereforethat his version would be the best way to refer to mwi) (with it's consequenses) aren't that populair at all among scientists. Also I got 6 reactions (one I didn't mention in the poll) which also got clear refutations of ANY mwi at all (and perhaps it isn't really relevant this includes a recent nobel laurate, and if I'm not mistaken one older nobel laurate, but I deleted the mail adress so I can't vouch for that) . And I'm sorry but I assume these aren't the only ones in the poll who voted c who rejected any mwi, because the people that did mention this did this while this wasn't itself being asked , actually I think it's most likely the majority did. And very most likely almost everyone rejected the copies idea. That being said 6 already is already more percentage wise then david raub's poll, but that I think isn't really relevant because of the very logical conclusion that in the randomly (only because of there reputation selected) participants in the poll reject MWI.
So this poll is in my opinion (and this opinion is so logical I don't think you can succesfully refuted) is relevant if you want to know what phycisists who think a lot about quantum mechanics think.
So please stop putting mist on very clear things. Also I must say I agree with Ken G's beginning of the post.
And I'm serious, it may sound a bit harsh, but will you (and I mean everyone on this forum) please stop posting things that just don't make sense (not because it's against my own personal opinion, but just because it doesn't make sense, and confuses people, you can of course advocate every opinion you like) so I don't have to come back here and post obvious posts again and again.

 

[kith]

This poll is nonsense.

First of all, your options are very poorly defined. An interpretation of a physical theory is always an interpretation of mathematical objects and their relations. So in order to get useful options for a survey, the first step is to present a generally accepted mathematical formulation of the theory. The second step is to choose different -well-known to be consistent- ways to interpret the mathematics in physical terms. And the third step is to draw conclusions from these interpretations.

You only did the third step, which of course is not do-able in a satisfactory manner if you skip the first two. So you chose two popcultural statements which have something to do with the MWI, and added the options to contradict them or be indifferent. How shall such a survey be able to produce reasonable results?

Plus, your survey is not at all representative. Why do you think these 30 people represent the physics community?

 

[eqblaauw2]

This poll is nonsense.

First of all, your options are very poorly defined. An interpretation of a physical theory is always an interpretation of mathematical objects and their relations. So in order to get useful options for a survey, the first step is to present a generally accepted mathematical formulation of the theory. The second step is to choose different -well-known to be consistent- ways to interpret the mathematics in physical terms. And the third step is to draw conclusions from these interpretations.

You only did the third step, which of course is not do-able in a satisfactory manner if you skip the first two. So you chose two popcultural statements which have something to do with the MWI, and added the options to contradict them or be indifferent. How shall such a survey be able to produce reasonable results?

Plus, your survey is not at all representative. Why do you think these 30 people represent the physics community?

I don't think they represent it, I think it's only a very good indication because they where randomly selected and all where very much highly regarded, and the most likely thing is that these participants where in fact more in favor in respect to 'normal' physicists, because they where all theoretical physicists and cosmologists. Maybe according to your definition a good poll must have a formula, but I think the physicists where aware of the formula of bryce, and if not they knew that A and B contained copies and parallel universes and that's the main thing, and if they did subscribe to this general notion they WOULD mention it (think, I didn't do a poll course, but this is **** logic, maybe it does not meet your scientific standards, but it does meet the standards of sense and that's what matters and should be the main reason you should have scientific standards in the first placee) for the rest your post is clearly a reaction of someone who has in this case only thinks in general rules and not by himself (a bit like someone who stops at a red light, when you are the only person in the world) cause this poll no matter how you interpret it, does refute raub. And I'm not going to repeat the obvious reasons besides what I said in this post. And if you like you can of course do step 3 yourself, though I suggest you do it with some logic.
byebye

 

[Hlafordlaes]

... And I'm serious, it may sound a bit harsh, but will you (and I mean everyone on this forum) please stop posting things that just don't make sense (not because it's against my own personal opinion, but just because it doesn't make sense, and confuses people, you can of course advocate every opinion you like) so I don't have to come back here and post obvious posts again and again.

I liked your poll as a contribution to the discussion, but I like the discussion even more. There are many useful insights apart from strict MWI-or-not, not least of which relates to the relative value, and role, of theory. Fra's musings on some deeper work he is doing, and Ken G's trademark cautionary reasoning are lots of fun! So, no need to come back and post anything over and over again; let's just enjoy the journey, whatever the destination.

 

[eqblaauw2]

I liked your poll as a contribution to the discussion, but I like the discussion even more. There are many useful insights apart from strict MWI-or-not, not least of which relates to the relative value, and role, of theory. Fra's musings on some deeper work he is doing, and Ken G's trademark cautionary reasoning are lots of fun! So, no need to come back and post anything over and over again; let's just enjoy the journey, whatever the destination.

thank you for your nice comment. I just wanted to say that I find it insulting (and I normally dislike that word) that someone said that the poll I conducted is nonsense , especially when someone (me in this case) has really put energy in it. And the statement is also utterly ridiculous (and for this I have given plenty enough arguments). I hope most will agree, and I hope this will be the last post. I still got some evidence (a mail I sent to all the participants to inform them about the results, so if you really doubt my honesty you can send me a message and I will post it to you).
I can also say this poll is conducted because I really wanted to know what highly regarded physicists thought about this subject, and that I used it also for my own information and I wouldn't let myself to be easily convinced, because I really wanted to get a true reliable result to get the uncertainty out of my head. I also will say that I would be depressed if everyone voted a or b, but that would be the price I had to pay. Luckily for me, and some certain person with a psychosis, this is not the case.

 

[nazarbaz]

Actually I would argue, as pertinent to MWI, that this is precisely what we can not infer. Making scientific progress does not require, and probably does not even suggest, that we are getting "closer to the right picture." I say this for three reasons:
1) scientific progress is always measured in terms of the increasing power it gives us over our environment and the increasing accuracy in our predictions, never by how right our picture is,
2) the pictures change so dramatically with each increment of accuracy and predictive power that no convergence of the "pictures" is in evidence, and there is also no direct connection between how much the picture changes and how much the accuracy improves,
3) there is no scientific evidence whatever that there is any such thing as "the right picture" that we could be moving "toward" in the first place.
These are important facts to bear in mind, because otherwise we fall victim to the same kinds of unjustifiable conclusions we turn up our noses at in pseudo-scientific endeavors.

That's exactly what I'm criticizing. The "dichotomy" of the "scientific accuracy" and the "ontological claims" behind it is not obvious to me. It is meaningless to talk about accuracy and progress if our well known theories doesn't tell us something about the world. What accuracy do we talk about otherwise ? Consistency with its own premise ? Aren't confusing science and circular thinking ?
I'm not pretending that our actual theories are fully describing the whole process, I'm not even assuming that they will one day, I'm just asserting that our actual knowledge is describing correctly some aspects of nature. No way to save the scientific point of view without this assumption, and no way to explain the efficiency of technology.
But science is neither reducible to philosophy nor technology even if it needs them to think it's own status and direct its practice. It is all about linking propositions and objects consistently despite what the diffuse postmodernist culture tells us. In that sense, the most dangerous threat science must face is the epistemological nihilism that some esthetes instilled in our understanding of it.

 

[nazarbaz]

I'm sorry but this must be one of the biggest pieces of crap I have ever read.
The newest theory (because at this moment I came up with it) is that the universe is a game played by Crocodile Harry, who has an Oedipuscomplex, and bad teeth.

I do however think a poll can indicate what the sciense community generally thinks at a certain moment, and that what the sciense community thinks generally is more correct then what the sciense community thinked in the past. However at this point the newer theory (MWI) isn't a populair theory at all (as I think I succesfully demonstraded). If and this is a big if, because I think if you do some reliable research you will find that there are other interpretations still more populair then MWI, MWI is the most popular theory that also doesn't mean it is a populair theory since the majority clearly rejects it. Then the most populair idea would be we don't know. But again this is an if, because the MWI theory isn't that populair at all (more populair then you would think at first notice when you read the rather extreme point of view, but still not close to being populair).

P.s. sorry that I couldn't resist login in again, but I really hate ********

Wonderful theory... Stop thinking, that's the climax of science... Crocodile harry...

 

[Ken G]

The "dichotomy" of the "scientific accuracy" and the "ontological claims" behind it is not obvious to me.

Then I'll give you some examples:
1) Aristotelian vs. Newtonian vs. Einsteinian gravity. The represents a clear sequence in converging accuracy-- Aristotelian is not quantitative at all, Newtonian is magnificently accurate for celestial motion. In most applications, Einstenian gravity adds little in the way of increased accuracy, yet holds that gravity is not a force but a bending of spacetime-- two more different ontologies would be hard to find. Einstein's theory essentially widens the domain of high accuracy outcomes, so is clearly moving toward some kind of convergence in accuracy, but the ontology borrows nothing at all from Newton other than some dependence on mass.

2) Classical vs. Quantum mechanics-- again we have two theories that agree essentially completely on some scales of phenomena, but QM extends the domain of high-accuracy outcomes to smaller systems. So there is clearly a convergence of accuracy happening when you pass from CM to QM, but the ontology is completely different once again-- we go from motion being described by position as a function of time to motion being ruled by inobservable mathematical entities that only pass into the real domain when they are in some sense forced to choose a definite outcome by their environment.

3) Thermodynamics vs. Statistical Mechanics-- here we have general laws about how heat and temperature behave, accurate for large systems in thermodynamic equilibrium, transitioning into statistical rules that apply to systems of particles. The latter extends the accuracy of the predictions to systems with fewer particles and different kinds of interparticle forces. The ontology is again completely different-- thermodynamics is a continuous description, statistical mechanics is an atomic description.

And the list goes on. In each case, we find advances that extend the domain of accuracy from one theory to the next, exhibiting a clear convergence of predictive reliability, so show a clear "arrow of progress" in regard to predictive power. Yet, these advances are accomplished via radical shifts in the basic ontology, exhibiting no tendency at all for the ontologies to "converge" other than the most basic consistency requirement. And today, we have research into "string theory", another complete change in ontology, targeted at achieving accuracy improvements that are so tiny they as yet cannot even be probed by our technology.

I'm not even assuming that they will one day, I'm just asserting that our actual knowledge is describing correctly some aspects of nature.

All well and good to say, but what does this really mean? When gravity was a force, was that "actual knowledge" of some aspect of nature, even when it became a curvature of spacetime? Or when it is something that strings are doing? All we ever get to know is the accuracy of our predictions.

 

[eqblaauw2]

STRAWMAN ALERT

Wonderful theory... Stop thinking, that's the climax of science... Crocodile harry...

-

stop thinking? where did I exactly promote this idea? you seem to suggest that newer theories are better then older ones, I don't agree with that, and I gave an example where that idea could logically lead to. This of course doesn't mean that newer theories not in the majority couldn't be true, it just means that you cannot say that they are most likely better because they are newer.If you meant to say that newer theories close to being generally accepted theories or at least have a majority are more likely to better then the older theories I fully agree with you. This standpoint of course doesn't mean that newer theories not hold by the majority of physicists couldn't be true, it just means that you cannot say that they are most likely better because they are newer.
P.s. sorry for being a bit rude in the previous post. But I stay with my point, without the rudeness.
I also wanted to say that I also got a email from an eminent physicist (I don't now who it was anymore, so you may just ignore it if you don't think it's useful, because I've got serious lack of evidence to back it up, I know it's true, but I can understand that you won't believe I got this email, this is a really long sentence ) that said that mwi isn't inconsistent. That's another argument then usually is being brought foreword , but you might look into that, if you want, if you just think it's evidentially bull it would be a little pointless.

 

[Hlafordlaes]

... And the list goes on. In each case, we find advances that extend the domain of accuracy from one theory to the next, exhibiting a clear convergence of predictive reliability, so show a clear "arrow of progress" in regard to predictive power. Yet, these advances are accomplished via radical shifts in the basic ontology, exhibiting no tendency at all for the ontologies to "converge" other than the most basic consistency requirement...

All well and good to say, but what does this really mean? When gravity was a force, was that "actual knowledge" of some aspect of nature, even when it became a curvature of spacetime? Or when it is something that strings are doing? All we ever get to know is the accuracy of our predictions.

I think the confusion I often have is, on one hand, the obvious value of our everyday mental models, based on unexpressed "theories" about how the world works, and which by their practical results seem to indicate we are in close touch with reality. OTOH we have scientific theories that delve into modeling that which is beyond the everyday and shift radically in ontology, as you point out in 1-2-3.

I tend to transfer the idea that we are capable of mentally modeling our environment accurately enough to survive and prosper, to the misguided idea that scientific theories converge on a true description in similar fashion. Still, it does seem that at least in part we do uncover new realities, such as, say, a predicted particle that is found and measured only as a consequence of a theory. That isn't only predictive power, is it? I mean, aren't we also uncovering something "real" and converging in some way on a more accurate description?

 

[Ken G]

Still, it does seem that at least in part we do uncover new realities, such as, say, a predicted particle that is found and measured only as a consequence of a theory. That isn't only predictive power, is it? I mean, aren't we also uncovering something "real" and converging in some way on a more accurate description?

I think what you're basically saying is, if we drop a block, a coin, a doll, a horse, a jack, and a toy car, and they all fall, have we not learned something about our reality that allows us to expect that when we drop a book it will fall too? I think the answer is yes-- we learn consistencies of experience, which we can then reliably generalize to "similar" situations via some sort of unifying theory, even if we can't ever be exactly sure what is going to prove similar and what isn't (like, when we drop a leaf in the wind and it blows away instead of falling). But consistencies of experience that we give a name to, like "gravity" or "conservation of energy" are not quite the same thing as an ontological description. What is it about gravity that requires that things fall? What is it about energy that requires it be conserved? Those are the kinds of questions, the "what's really going on here" kinds of questions (similar to interpretive questions about quantum mechanics or any other theory), that never seem to reach any kind of convergence in the progress of science. I think it is easy to overlook that, and tell ourselves things that simply aren't in evidence, when we imagine some kind of "destination" for scientific understanding rather than the simple process of doing science. That's why I'm skeptical of using science to create worlds views, such as a belief in the actual existence of "many worlds."

 

[Hlafordlaes]

... and a toy car...

gosh, Ken G, gimme a break

... That's why I'm skeptical of using science to create worlds views, such as a belief in the actual existence of "many worlds."

and he deftly puts the thread back on track...

 

[nazarbaz]

Then I'll give you some examples:
1) Aristotelian vs. Newtonian vs. Einsteinian gravity. The represents a clear sequence in converging accuracy-- Aristotelian is not quantitative at all, Newtonian is magnificently accurate for celestial motion. In most applications, Einstenian gravity adds little in the way of increased accuracy, yet holds that gravity is not a force but a bending of spacetime-- two more different ontologies would be hard to find. Einstein's theory essentially widens the domain of high accuracy outcomes, so is clearly moving toward some kind of convergence in accuracy, but the ontology borrows nothing at all from Newton other than some dependence on mass.

2) Classical vs. Quantum mechanics-- again we have two theories that agree essentially completely on some scales of phenomena, but QM extends the domain of high-accuracy outcomes to smaller systems. So there is clearly a convergence of accuracy happening when you pass from CM to QM, but the ontology is completely different once again-- we go from motion being described by position as a function of time to motion being ruled by inobservable mathematical entities that only pass into the real domain when they are in some sense forced to choose a definite outcome by their environment.

3) Thermodynamics vs. Statistical Mechanics-- here we have general laws about how heat and temperature behave, accurate for large systems in thermodynamic equilibrium, transitioning into statistical rules that apply to systems of particles. The latter extends the accuracy of the predictions to systems with fewer particles and different kinds of interparticle forces. The ontology is again completely different-- thermodynamics is a continuous description, statistical mechanics is an atomic description.

And the list goes on. In each case, we find advances that extend the domain of accuracy from one theory to the next, exhibiting a clear convergence of predictive reliability, so show a clear "arrow of progress" in regard to predictive power. Yet, these advances are accomplished via radical shifts in the basic ontology, exhibiting no tendency at all for the ontologies to "converge" other than the most basic consistency requirement. And today, we have research into "string theory", another complete change in ontology, targeted at achieving accuracy improvements that are so tiny they as yet cannot even be probed by our technology.
All well and good to say, but what does this really mean? When gravity was a force, was that "actual knowledge" of some aspect of nature, even when it became a curvature of spacetime? Or when it is something that strings are doing? All we ever get to know is the accuracy of our predictions.

1. What is problmatic with your view is the fact that you treat the aristotelian, Newtonian and einsteinian physics as equivalents, almost like there is no progress over time and no widening of our perception of the universe.
2. There is a certain trivialization of science findings in your approach and I suspect that you are confusing science facts and scientific hypotheses. If you are right : does it mean that the electron is an "interpretation" of something unreachable to our brains and that light bending next to huge masses is a "metaphor" ? If yes, justify it.
3. My main argument is the fact that our actual science is well grounded relating definite objects with consistent propositions, not general ontological claims with profound global theories. What is matter and energy ? How the universe was born ? That's exactly our wide margin of progress.
4. As I told you, your approach could be useful with highly hypothetical claims but cannot stand as foundation to an epistemology. Somehow you're urging science to give an explanation to almost everything in order to give it the right to make ontological claims, which is not reasonable.
5. The radical distinction between "calculation" and "ontology" seems like a fallacy. In physics, there's no other way to study our objects of interest than mathematics. To find or decide which mathematical model could give us an insight on the object is the main goal of science. The process is obviously contingent, not all of our physical theories are equally right or close to the true nature of objects. Remember : the relation between the subject and the object is the essence of the scientific experience.
6. Science is a work in progress with both nicks and continuities. So nuance.

 

[eqblaauw2]

1 So you think science has progress (a view In my opinion also adequately defended by Popper, so I agree with you)
2 but you agree with me that newer theories aren't in itself better then older ones (a statement that cannot be derived from point (1). (if that's what you said, my english isn't perfect)
I also agree with you (again if that's what you're trying to say) that if we talk about mwi it would be better if we all would talk about mwi with parallel universes and copies of ourselves, because that would help a lot of confusion out of the way. (that's also the 'version(s)' of mwi (s) that I at least tried to get clear in my poll))
That being said the drastically ontological claims, just like a theory being newer isn't an argument for it's quality, aren't itself an argument for it's quality. Most physics find 'that' mwi a bridge to far, and they have their reasons.
I don't want to make a discussion about mwi impossible, I just want to make the discussion fair and square.

 

[BruceW]

I also agree with you (again if that's what you're trying to say) that if we talk about mwi it would be better if we all would talk about mwi with parallel universes and copies of ourselves, because that would help a lot of confusion out of the way. (that's also the 'version(s)' of mwi (s) that I at least tried to get clear in my poll))
That being said the drastically ontological claims, just like a theory being newer isn't an argument for it's quality, aren't itself an argument for it's quality. Most physics find 'that' mwi a bridge to far, and they have their reasons.
I don't want to make a discussion about mwi impossible, I just want to make the discussion fair and square.

About earlier, I understand that you put energy into making a poll, which is good, and I didn't mean to say that it was useless. I just meant to say that it helps to define exactly what you mean when you say 'MWI' or 'CI'.

You've said here that your poll was on the MWI of 'literal' parallel universes. This is very different to the MWI of 'no non-unitary collapse'. Did you explain to the people you were polling that you wanted to know their opinion on 'literal' parallel universes? Because its important that all the people you polled were answering the same question.

For example, for me, I think 'no non-unitary collapse' is a useful interpretation. And I think allowing non-unitary collapse is also a fine interpretation (as long as the non-unitary collapse happens only for the 'end-user' of the calculation). But I think any interpretation that uses the existence of parallel, non-interacting universes to be totally ridiculous.

Although, if that interpretation can be used to predict physical phenomena, and if it agrees with all experimental results, then it is still not really 'wrong'. Its just that it makes unnecessary postulates, in my opinion.

 

[eqblaauw2]

About earlier, I understand that you put energy into making a poll, which is good, and I didn't mean to say that it was useless. I just meant to say that it helps to define exactly what you mean when you say 'MWI' or 'CI'.

You've said here that your poll was on the MWI of 'literal' parallel universes. This is very different to the MWI of 'no non-unitary collapse'. Did you explain to the people you were polling that you wanted to know their opinion on 'literal' parallel universes? Because its important that all the people you polled were answering the same question.

For example, for me, I think 'no non-unitary collapse' is a useful interpretation, and so is allowing non-unitary collapse as an interpretation. But I think any interpretation that uses the existence of parallel, non-interacting universes to be totally ridiculous.

Although, if that interpretation can be used to predict physical phenomena, and if it agrees with all experimental results, then it is still not really 'wrong'. Its just that it makes unnecessary postulates, in my opinion.

yes I did, I said in the introduction as clear as I could that the poll was only relevant for the mwi that stated that there where parallel universes and copies, that actually existed. I don't know if I used the word literally, but I think there was no reason what so ever why you could think this wasn't meant to be taken literally. I think how I said it thus maid it clear that I was interested in the opinion of the literally existence of those universes and persons.
That being said 6 persons of the 28, and the 18 that voted c said (without being asked) informed me that they disliked any version of mwi whatsoever (that they where aware of).
(you can read the poll on the site, but I didn't mention the introduction I think)

 

[Ken G]

1. What is problmatic with your view is the fact that you treat the aristotelian, Newtonian and einsteinian physics as equivalents, almost like there is no progress over time and no widening of our perception of the universe.

Why would anyone treat those as equivalents?

2. There is a certain trivialization of science findings in your approach and I suspect that you are confusing science facts and scientific hypotheses.

Well I see no trivialization, I just see the unembellished facts of the situation. If we stick to what there is actual evidence of, then it is what I said.

If you are right : does it mean that the electron is an "interpretation" of something unreachable to our brains and that light bending next to huge masses is a "metaphor" ?

Yes, I would say those things are pretty obviously interpretations and metaphors, that's what scientific ontology always is.

If yes, justify it.

What requires justification is anything else. It is clearly the null hypothesis that these things are interpretations and metaphors. What do you think they are, and how can you make a logical argument they are that?

3. My main argument is the fact that our actual science is well grounded relating definite objects with consistent propositions, not general ontological claims with profound global theories. What is matter and energy ? How the universe was born ? That's exactly our wide margin of progress.

Hmm, you know what matter and energy are? You know how the universe was born? The rest of us are all ears.

4. As I told you, your approach could be useful with highly hypothetical claims but cannot stand as foundation to an epistemology.

And where did I say I was laying out a foundation for an epistemology? That's the scientific method, we already have that.

Somehow you're urging science to give an explanation to almost everything in order to give it the right to make ontological claims, which is not reasonable.

I am? Almost everything? I'd settle for just one thing, actually, one explanation that "gives us the right" to make ontological claims. And what happens when that explanation gets replaced by a totally different one with a completely different ontology?

5. The radical distinction between "calculation" and "ontology" seems like a fallacy. In physics, there's no other way to study our objects of interest than mathematics.

So calculations are ontology? That is the claim you are making? Have you really thought that through?

To find or decide which mathematical model could give us an insight on the object is the main goal of science.

Yes, here you are making sense. Insight, not ontology.

Remember : the relation between the subject and the object is the essence of the scientific experience.

Agreed, this is a demonstrable crux of the scientific method.

6. Science is a work in progress with both nicks and continuities.

Yes, it is a work in progress. So that is an argument that ontologies do converge?

 

[Ken G]

1 So you think science has progress (a view In my opinion also adequately defended by Popper, so I agree with you)

Yes, science demonstrably makes progress.

2 but you agree with me that newer theories aren't in itself better then older ones (a statement that cannot be derived from point (1). (if that's what you said, my english isn't perfect)

Which theory is "better" is highly context dependent, yes. Which theory has a "truer ontology" is highly questionable. Ontologies behind theories are fascinating glimpses into the meaning of a theory. Reality is another matter.

I also agree with you (again if that's what you're trying to say) that if we talk about mwi it would be better if we all would talk about mwi with parallel universes and copies of ourselves, because that would help a lot of confusion out of the way.

I wouldn't presume to tell people who use MWI how they should use it, except to say that they should use it for what interpretations should always be used for-- a way to motivate a sense of understanding of a theory in a way that resonates with some set of philosophical priorities. They should not confuse themselves that they are talking about some reality that is independent of those priorities.

Most physics find 'that' mwi a bridge to far, and they have their reasons.
I don't want to make a discussion about mwi impossible, I just want to make the discussion fair and square.

I agree that in my experience, most physicists are not as drastically rationalistic as is required to see MWI as a "truth" about reality.

 

[juanrga]

Hello,

While the majority of physicists embrace the Many Worlds interpretation of quantum decoherence, I am holding out hope for the Copenhagen interpretation or better yet, a undiscovered interpretation.

Please allow me to pose three problems I have with the MW interpretation.

1) There is a nonzero prob of me spontaneously becoming a miniature sun. Let me elaborate. Since I am made of atoms, there is a nonzero prob that all of the subatomic particles comprising each of the nuclei of my atoms are all one kilometer away except for a single proton and single electron in each atom. I.e. I am now spontaneously comprised of only hydrogen atoms. Now let's say that since even the exact position of these hydrogen atoms is uncertain they are close enough that gravity overpowers all and nuclear fusion takes place. I.e. I have become a miniature sun.

The probability of this happening is obviously miniscule, but nonzero. With the CI interpretation this will never happen because the probability is so small that the universe is not old enough for such a low probability to have been realized. However with MWi since the probability is nonzero, it has happened. Moreover it has been happening every second of every day since the minute I was born in some parallel universe.

2) My second problem with MW intepretation is how can an interference pattern result in a double slit experiment if the particle is actually traveling through a different slit in separate universes. Shouldn't the interference only occur if the particle is traveling through both slits simultaneously in the same universe?

3) My third problem with MW is that it really does away with the concept of probability although many quantum experiments have shown that the concept does exist. For example, take a weighted coin which is 99% more likely to flip heads, than tails. CI predicts that a 100 flips would yield 99 heads and 1 tail. With a single flip, one is much more likely to get a head than a tail. However with MW, one flip will result in head in one universe, tail in another so therefore 50-50 probability.

Can someone help me to understand these issues any better? Thanks!

The standard interpretation is the Copenhagen one. Many worlds (MW) is a collection of nonsense as has been repeatedly showed in the literature. It is still maintained alive from people who do not understand QM.

Maybe you would take a look to Streater list of lost causes in physics, the section about MW: http://www.mth.kcl.ac.uk/~streater/lostcauses.html#XII

 

[eqblaauw2]

The standard interpretation is the Copenhagen one. Many worlds (MW) is a collection of nonsense as has been repeatedly showed in the literature. It is still maintained alive from people who do not understand QM.

Maybe you would take a look to Streater list of lost causes in physics, the section about MW: http://www.mth.kcl.ac.uk/~streater/lostcauses.html#XII

well that's a little bit strong (although I think I agree with you, it's a possibility that this statement causes a strong reaction of people who feel misjudged).
Maybe, to be a little arrogant, my poll is a better way to make a similar (tough a little less strong) point. Do I think it wouldn't be bad to read the website you mention.

 

[nazarbaz]

Why would anyone treat those as equivalents?
Well I see no trivialization, I just see the unembellished facts of the situation. If we stick to what there is actual evidence of, then it is what I said.
Yes, I would say those things are pretty obviously interpretations and metaphors, that's what scientific ontology always is.
What requires justification is anything else. It is clearly the null hypothesis that these things are interpretations and metaphors. What do you think they are, and how can you make a logical argument they are that?
Hmm, you know what matter and energy are? You know how the universe was born? The rest of us are all ears.
And where did I say I was laying out a foundation for an epistemology? That's the scientific method, we already have that.
I am? Almost everything? I'd settle for just one thing, actually, one explanation that "gives us the right" to make ontological claims. And what happens when that explanation gets replaced by a totally different one with a completely different ontology?
So calculations are ontology? That is the claim you are making? Have you really thought that through?
Yes, here you are making sense. Insight, not ontology.
Agreed, this is a demonstrable crux of the scientific method.Yes, it is a work in progress. So that is an argument that ontologies do converge?

Your approach is not scientific, it is philosophical. The progress means the ability to meet and understand, even partially, the objects, not to make calculations about them. I am of course aware that we are far away from being able to make sense of the physical world but I manage to make a room for it in the near or the far future. Because that's the true mission of science.
I was right, you are a postmodernist who lives in "interpretations", "narrativities" and "metaphors". What kind of effectivity could have a technology if we don't have the shadow of a clue of what things are... ? Magic, maybe ?

 

[eqblaauw2]

Your approach is not scientific, it is philosophical. The progress means the ability to meet and understand, even partially, the objects, not to make calculations about them. I am of course aware that we are far away from being able to make sense of the physical world but I manage to make a room for it in the near or the far future. Because that's the true mission of science.
I was right, you are a postmodernist who lives in "interpretations", "narrativities" and "metaphors". What kind of effectivity could have a technology if we don't have the shadow of a clue of what things are... ? Magic, maybe ?

Well I have serious doubts that people who are working and thinking about that technology and don't subscribe to mwi don't have a serious clue.
Of which we have a good indication they are in the majority don't have the slightest clue. I believe according to Tegmark even in quantum computing they are in the majority, if you want to take the polls tegmark conduct, or cites *I don't know who conducts those polls he cites*, seriously, but let's just do for the sake of good faith. (David Raub is another case, because I think I refuted that poll successfully. Although you're entitled to have your own opinion about that).

The poll (talk about a vague poll):

An informal poll taken at a conference on quantum computation at the Isaac Newton Institute in Cambridge in July 1999 gave the following results:

Do you believe that new physics violating the Schro ̈dinger equation will make large quantum com- puters impossible? 1 yes, 71 no, 24 undecided
Do you believe that all isolated systems obey the Schro ̈dinger equation (evolve unitarily)? 59 yes, 6 no, 31 undecided
Which interpretation of quantum mechanics is clos- est to your own?
(a) Copenhagen or consistent histories (including postulate of explicit collapse): 4
(b) Modified dynamics (Schro ̈dinger equation modified to give explicit collapse): 4
(c) Many worlds/consistent histories (no col- lapse): 30
(d) Bohm (an ontological interpretation where an auxiliary “pilot wave” allows particles to have well-defined positions and velocities): 2
(e) None of the above/undecided: 50

But even if you do think that. It's still isn't an absurd conclusion that we have technology that we don't have the slightest clue how it works.
that doesn't have to involve magic. People have worked with technology that involved gravity for ages, while they hadn't (and some might say still don't) have the slightest clue how it works.
Also the 'technology' you seem to refer to is very controversial (there isn't a quantum computer that I know of yet, if you might want to imply that, but I don't know if you do since you don't really seem to make it clear what you mean).
sorry