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The Hidden Reality Draws Ire From Physicists
eldavojohn writes "Scientific American is running a piece by science journalist John Horgan attacking pop physicist Brian Greene's latest offering, titled The Hidden Reality. He's not entirely alone; Not Even Wrong backs him up and reminds us of a growing list of multiverse propaganda. The journal Nature ran a short piece (subscription required) trying to remind everyone that Greene's book is more theory than fact, but apart from those three responses, the popular press seems to be gobbling up this tantalizing concept of a multiverse. NPR offers an excerpt while SFGate and The Wall Street Journal entertain us with interviews of the controversial Greene. The New York Times and Salon seem to think it's worthwhile, with Salon even calling it 'the science behind' the multiverse theory. The New York Times thought it worthwhile to give Greene an op-ed column. For better or for worse, Greene has certainly brought this great debate to the public's attention — similar to his exhibition of String Theory."
what does it have to do with this world? multiverse cannot be science, it's talking about unobservables.
if we entertain the thought of multiverse, we might as well entertain the thought of a God. what's the difference?
The press repeating pseudoscience as fact? Say it ain't so!
There's no -1 for "I don't get it."
His sole beef is that it's impossible to prove or disprove. I don't suppose he'd mind if we at least thought about it? From the tone of the article it seems he'd rather we worry about what's possible, rather than flights of fancy. If we worried about the possible, what would we really have?
You can check out a fairly entertaining interview of Brian Greene by Stephen Colbert from last Thursday on Colbert's web site.
I can't say this will educate you further one way or another and I am certainly not qulified to weigh in on either side of the debate but the guy was pretty candid with Stephen and, well, I found it entertaining...
Creationist Textbook Stickers Declared Unconstitutional by CowboyNeal
But the conservation of ire insures that an equal amount of economists will chill out.
This means that I can travel to the other universes, kill off the me from other ones and become stronger? I am pretty sure that the awesome Jet Li movie came out first (seriously, when he is going in regular motion and the sparks are in slow motion at the end, awesome). And yes, this is all 100% on topic since the movie discusses the multi-verse (it is not everyday that I can figure out a way to shove a Jet-Li reference into /.)
The world is how you make it
Sounds like the submitter doesn't know the meaning of the word theory?
Now tell me about a scientific fact, proposing that we talk about empirical science here.
CC.
TaijiQuan (Huang, 5 loosenings)
more theory than fact
To scientists, these terms are not mutually exclusive.
What's so freakin' hard about getting that concept right? Oh, yeah, people can't spell (much less pronounce) "hypothesis".
The term theory only colloquially means conjecture.
A scientific theory is something that does have fact backing it up!
http://en.wikipedia.org/wiki/Scientific_theory
OK, it seems that even people who should know the difference can't distinguish between the word theory and hypothesis. What was meant in the write up when this was said "Greene's book is more theory than fact" is "Greene's book is more hypothesis or conjecture rather than theory". A theory has been tested and more than once. It is as close to fact as humans can get. This watering down of the word theory is bad, it causes people to be confused and discount theories. Which is why people doubt the theory of evolution or global climate change.
Use the word right or don't use it.
OK, I'll stop ranting.
putting the 'B' in LGBTQ+
...where this book is up for a Pulitzer, so sticks and stones, ya haters!
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Prisencolinensinainciusol. Ol Rait!
I think the problem is that some of the stuff is neither hypothesis (a testable conjecture) nor theory (a tested unfalsified hypothesis) but simply conjecture and speculation.
Fine. I'm totally fine with that. I have no trouble with the public being slightly misled or confused about a rational dissection of the universe instead of debating the benevolence of angels on Oprah or wondering if the invisible man in the sky made us as is or just guided evolution. This is progress people. Progress. Give Dr Greene a break. He's just trying to make a living like the rest of us and he's doing some fair amount of good in the process.
Why all the negative spin in the summary? As far as I can tell, nobody is accusing Greene of "propaganda." Rather, this is /. propagandizing at its absolute worst.
Here's the real summary: Brian Greene has written on string theory for a popular audience in the past, and he's also fascinated by some of the more fringe-y elements of physics, such as the multiverse theory. He has a new book out. He has not taken any public stance on the Tea Party, abortion, or the Iraq war -- and honestly, I think it's sad that it seems to have become a requirement of modern journalism to pretend that he has.
Breakfast served all day!
The guy is out on the most feeble of limbs with his multiverse idea, since 'string theory' itself is little more than conjecture... but to take the edge off the 'not science' rhetoric here, the guy is a very well regarded theoretical physicist. Is it any less scientific-wild-ass-guess than Hawkings' notions about black holes? No. He at least has enough clout to get data access to the CERN supercollider experiments, so its not like its -me- throwing this crap out there hoping it will stick.
I read Fabric of the Cosmos and thoroughly enjoyed it. I then read the Elegant Universe and grew more and more frustrated with each page as Greene delved into theories that can never be proven or disproven. At a certain point, this become little more than fantasy and has as much credibility as religion and mythology, both of which can also never be proven or disproven.
In a parallel universe, Brian Greene is lauded as a genius and his interpretation of multiverse theory is universally accepted!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Science popularizers like Greene have to tread a careful line. They're not paid to talk about the most important work, which most people wouldn't understand. Real cutting-edge physics is comprehensible only to those extremely skilled in the art, which cuts out even the vast majority of scientists. But people like believing that they're getting dispatches from the front, especially in physics, because that's where people imagine lays the answer to Life, The Universe, and Everything.
You can't even pretend to know much about string theory without some very advanced work in quantum mechanics AND general relativity, which means knowing an awful lot of very, very difficult calculus. For 99.9% even of readers of Scientific American, they're skipping straight past all of that.
Which means, in essence, telling comforting lies. That's common in education, simplifying a subject to the point where it's essentially false. It's common in science (cf. genetics), but in other fields as well. History, as taught in schools, is so far from reality that college professors have to spend a full year (at least) undoing the damage.
It's similar to the situation with space research: most of the actual science is done by the robots, but people like the human stories associated with manned flight. The real science is done practically with the rounding errors in the budget.
In the case of string theory, that means that a bunch of people doing interesting but (bluntly) irrelevant speculation get far, far more attention than they deserve. It's not that they're right, wrong, or Not Even Wrong. People want to know what they're doing, because they've been told that we're Just Around The Corner from The Big Answers. It's a lie, and essentially everybody familiar enough with the work knows it. But they also know it's where the funding comes from.
I mean seriously... a multi-billion-dollar supercollider? How on earth does that get funded? Because a bunch of people who can't tell a fermion from a boson imagine that they're part of a grand human experiment. And maybe, in the grand human scheme of things, it is worth the money, though I personally doubt it. Still, it's the dirty little secret of scientific work: popularizers write a lot of books about stuff that's really of very little earthy interest, in order to attract enough attention to the field of science to keep the actual work going on. The grad students counting bacterial colonies or coming up with new protein folding algorithms or other tedious stuff that slowly an un-telegentically advances understanding.
I don't like the little turf war going on between the string theoriests, who get more attention than they deserve, and the anti-string-theorists, who are doing equally unproductive work. Both are intriguing speculations that might one day be of intense interest, but at the moment are of little value either practical or philosophical. They get attention only because they're right at the edge, but most of us are so far from the edge that they'd be invisible under any other circumstances. Both should be left to labor diligently in quiet, and let their little funding turf war be lumped in with the rest of the academic bickering rather than become a great philosophical debate.
So respected scientists write about a theory of how the universe really is, and these journalists work themselves into a tizzy and attack their writings as if they were some sort of moral outrage? Which side has the ignorant savages on it again?
For my part, I read David Deutsch's argument for multiverses in The Fabric of Reality over a decade ago and it seemed sensible, even if some of the other stuff in that book did not. You don't need string theory to argue in favor of a multiverse; even simple double-slit experiments appear to show that photons from different universes are somehow able to interact with (or collide with) each other.
Anyway, the bottom line is that most journalists are not physicists and have only the most superficial grasp of how the physical universe really works, which means they are totally unqualified to judge the value of these theories.
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He's selling the idea of a multiverse, but if he can't tell us how to get to Tanelorn nobody should take him seriously.
When information is power, privacy is freedom.
The problem as I see it is this: science deals with the observable universe- taking evidence that we can see and drawing conclusions from it. Alternate universes are obviously not a part of our universe, and as such we have no way of directly observing them- if they exist at all. This would in my opinion put them in the category of 'supernatural'. If we are going to call this 'science' then ghosts, god claims, unicorns, leprechauns and all other manner of supernatural claims can also be considered 'science' on the same grounds. It is OK to speculate on the idea but just understand that it is nothing more than that- speculation.
"more theory than fact"
That is a non-sequitur.
Someone who whines that the multiverse theory must necessarily be false because it leads him to uncomfortable conclusions regarding his personal belief in morality has no business criticizing any scientific theory, no matter how speculative it is.
And seriously people, pseudoscience? You are claiming that Susskind and Hawking engage in pseudoscience, like Deepak Chopra?
This criticism isn't based on scientific merit, this is envy of popular attention.
Nah. The multi-verse wave function (whatever it is) should be more or less smooth enough. By killing off all your "twins" you convert your wave function into Dirac delta function. I guess at that moment the multi-verse will respond with a loud "gulp" sound (in hard vacuum) and eliminate you and entire history of our your existence (also it will edit out all ./ logs, I guess).
Wait, to whom am I talking right now?
Horgan's argument can be redirected at himself. "Do better things with your and our time, Greene." Do better with your and our time, Horgan, and stop being a curmudgeon.
I'm not sure if "remind everyone that Greene's book is more theory than fact" was from Nature or the story submitter, but no wonder the general public is quite confused about science in general. The sentence implies that it's "just a theory" and that theories aren't highly thought of by scientists, yet the same types of people who object to Mr. Greene's work being though of as useful rant and rave when the theory of evolution is treated as anything other than fact.
If his work is a theory and is supported by enough empirical evidence that we assume it's correct in most circumstances, then it really is interesting and I'd like to know about it. If it's not, don't call it a theory (even if he does). Call it a hypothesis or science fiction or some such thing.
I've believed in a Multiverse since I was 12, before I dug my fingers into my Players' Handbook and DMG. If 20 million people play D&D, it must be true.
Remember kids, if you're not paying for the service, YOU ARE THE PRODUCT THAT IS BEING SOLD.
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String or M theory presents the possibility of a theory that doesn't need a ton of constants, just a description of a Calibu-Yau geometry, and the rest "falls out". It's that description that is currently lacking, the search space is enormous and makes a computer search for the answer to the traveling salesman problem look trivial. So yeah, it's far from proved, because it's far from done, and that step isn't in the cards till the right shape for that space is discovered.
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The multiverse also solves some otherwise very nasty problems in similar fashion, or it could.
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Neither is proved, of course, but they hold out the hope that a theory of everything is even possible, and the light was getting really dim on that -- so we can hope. All such things of course deserve skepticism, but until proved wrong, they are in some sense more right than the current models which we KNOW have to be wrong because they can't be reconciled with one another at the limits. They are just useful until we find something better.
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Such is science.
Why guess when you can know? Measure!
By that same logic, though, you can flush most of Einsteins work too. We do not posses, nor are we likely to posses in our lifetimes barring alien intervention, the technology to directly test and observe either the General or Special theories of relativity. The math works, its elegant, and is therefore the best explanation people can come up with. String theory tries to tie the quantum aspects together with the space time and forces described by AE. Its only as credible as the information that its based on.
Is that somewhere out there exists a universe where beer is free and all the girls look like Natalie Portman, and here I am stuck with you nerds reading flaimbait on slashdot.
No. Theory is not fact. Theory is a well tested and accurate model of the facts, but it is not the fact itself.
For example, the Theory of General Relativity does not precisely match up with reality as we see it. We're not exactly sure what's wrong with it right now, and the errors are ridiculously insignificant, but it is clear that it's not entirely fact. And despite not being fact, and despite being wrong at some ridiculously small epsilon, it is still by far the most accurate theory that we have.
And besides, if Theory were Fact, then Newton's Theory of Motion would still be true today, as it was when he formulated it, and it was widely accepted.
And of course a "theory" can be discredited, and falsified. Such as "Caloric theory".
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For they all are guilty of mental masturbation when it comes to physics. Oh, and include whomever postulated that the Higgs is so abhorrent to nature that it comes back through time to prevent its discovery.
It is a general "parallel universe" or "alternate reality" problem, and not any problem with your understanding. You (and everyone else) have failed to identify the matter/energy constraint. That is to say, if there is an alternative, it must be expressed in matter, and maintaining more than one reality requires additional matter (or base state of energy). I've conceptualized it with a familiar software developer concept: MVC: Model-View-Controller. Anytime when looking at gobs of data (including the state of reality) you need to look and interact with data in a uniform way. MVC allows for this. The model is the data model - the structure of, and data itself. List, tree, etc. The universe would probably express this as dimensional (3 or 10) planes of energy. Next is the view, with is the manifestation of the model. This would be an instantaneous snapshot of the universe, including velocities, etc. Finally the controller are the laws that work on the data. They do not work on the view, as the view is dependent of the model.
Every time you propose an alternate time line, then you need to copy the model (you can share the viewer and controller (if you didn't things would be "noticeably different")) But to copy the model is to acquire the energy to express a whole other universe, and not once, but at every decision point on the time line.
Physicists are just now starting to realize this and many are starting to argue that space-time is quantized on the order of Planck length (and time). While this is infinitesimally small, it vastly reduces the possible outcomes from infinite to a manageable number, possibly 1. Quantized space time locks down the source state and limits the possibilities of the next state, so it is feasible that the laws of the universe would only allow 1 possible next state. Heim was the first (that I know of) to argue for quantized space-time. I've since seen other people derive it on their own and get a similar (yet not identical) result
(but all are some close value to Planck length)
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
http://www.youtube.com/watch?v=iMm38apPNUs Charlie Rose - Lisa Randall 1/4
John Horgan is utterly misguided. He has apparently decided, for instance, that the entire field of Cosmology is a moral outrage because it doesn't gel with his myopic notion of how science should work. But contra to what he asserts, Science does not require direct evidence. No one will ever see a quark, for instance, with their own eyes. Or even with a microscope. We know that quarks are there because when we theorized their existence, it made our theories simpler and gave them more predictive power. Likewise for multiverses.
In any case, you don't have to take my word that multiverses are on sound scientific footing. There's an excellent article on the topic by the renowned cosmologist Max Tegmark in Scientific American here.
|>ouglas
P.S. Don't take any of this to mean that multiverses are now an accepted scientific fact, but they are a very plausible scientific theory for which we do have a significant amount of evidence. Also, Horgan's notion that scientists should stick to the more mundane is ridiculous. Scientific theories that promote wonder (especially if they have a good chance of being true) are essential for generating interest in science amongst the general populace, and for enticing future generations of scientists.
Huh? Both theories of relativity have been quite well tested, special relativity especially so. Mass-energy equivalence, time dilation and mechanics (where different from Newtonian) have all had experimental tests. Similarly, for GR, differences in Mercury's orbit, gravitational time dilation (Pound-Rebka experment) and so forth.
By that same logic, though, you can flush most of Einsteins work too. We do not posses, nor are we likely to posses in our lifetimes barring alien intervention, the technology to directly test and observe either the General or Special theories of relativity.
Well I guess then you must believe in alien intervention because its all happened already:
http://en.wikipedia.org/wiki/Tests_of_general_relativity
No one has a right to their *own* opinion. They have a right to the TRUTH.
From the TFA:
"Multiverse theories aren't theories—they're science fictions, theologies, [...]"
Theology is the keyword here. Postulating a multiverse with many similar universes to this one basically eliminates any objective significance this particular planet Earth with its history has. You can nuke everything and "know" that our culture will continue in other universes. So accepting a multiverse theory would destroy ethics: it would kill God.
I agree... although I live in a universe where we don't have atomic clocks, satellites, particle accelerators, atomic bombs, the planet Mercury, telescopes to observe the bending of light, etc. It is truly frustrating to live in the 18th century.
Procrastination Man strikes again!
More proof that we need to be able to moderate summaries
These posts express my own personal views, not those of my employer
Given the authors first sentence disclaimer, I can't fault his expression of well grounded opinion, but I can disagree.
I don't think investment bankers, or quants, are any less moral than vultures or other scavengers. They serve a valued role in eliminating mindless investors with too much money and redistributing fertilizer so more valuable species can take root.
Admittedly, we are all suffering right now from the after effects of some dead elephants. But they were dead before the vultures exposed their rot.
When I was reading cosmology many years ago, it struck me as philosophy. It still does. But philosophy is not bad, and not necessarily not science. Remember that science began as natural philosophy that threw out the all the previous assumptions of how the universe worked. The best science still throws out previous assumption. Assumptions like wave require a media, that we can produce an arbitrary energy, that things can be cut into arbitrarily small sizes, that we can measure things to arbitrary precision. It is also know that when scientist try to invalidate these treasured assumptions, the scientists that have built their careers on these assumptions will revolt.
Take General Relativity. It is a theory that makes some predictions, is getting increasing support, but is not as testable as the photoelectric effect which has many practical applications. These practical applications are key because such routine use of theory tends to validate it. Any theory that remains in the lab is simply going to be that, a theory. General Relativity is supported, it describes the way the universe might be, and is the simplest explanation, but it certainly does not explain how the universe has to be. This unlike QM, which due to the practical applications seems to describe how the universe works, at least within the domain.
So what we have in the book are a series of scenarios. IMHO the valid question to ask is does the data support these scenarios, do these scenarios fall out the math, and is there any chance that any of them can be tested. If the first two are true then, to me, they have some interest. If the data has to be cherry picked and the math is severely obtuse, that is an issue. Otherwise it is like the theory that there is one electron in the universe. It may be true, but it may not be useful or testable. That does not mean anyone should be outraged because someone brings it up.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
If every choice is available somewhere, why does probability work so well?
"Every choice" does not mean infinite choices.
Think of this: every molecule of air in the room is moving in some random direction, so there is a possibility that all of them will be moving in the same direction, with the consequence that the air pressure in one wall will be zero and the opposite wall will be blown apart by the air pressure, right?
Wrong. Every molecule is moving in a random direction, as a result of collision with other molecules. Assuming the existence of this "multiverse", it would *not* contain an infinite number of universes, only those universes that could be split by a quantum entanglement.
That is to say, there would not exist an universe where all the molecules of air are moving in the same direction, only universes where each molecule is moving in a possible direction as defined by its interaction with other molecules.
Probability is still maintained because "infinite" is so much larger than any number the multiverse could generate.
So maybe I'm a horrible 'literalist' (not sure there's a word for that, so I guess I'm ... not?) but there's only one Universe.
One.
Any other kind of 'verses' are all a part of this same Universe, that realm which encompasses all of existence. To include further things within the Universe is possible, but it is not possible to have more than one Universe. Even a "Multi" verse is yet still a "Uni" verse when one considers the whole as a single whole... as one without any logical doubt can do.
Therefore the "multiverses" would all still exist within the single Universe. For which reason I would prefer to remove the "verse" from "multiverse" and perhaps call it a "multicosmos" or something equally pointless in the general scheme of things except for which to sate my spontaneous lust for pedantry.
Disclaimer: I've been reading The Baroque Cycle.
I do not respond to cowards. Especially anonymous ones.
By that same logic, though, you can flush most of Einsteins work too. We do not posses, nor are we likely to posses in our lifetimes barring alien intervention, the technology to directly test and observe either the General or Special theories of relativity. The math works, its elegant, and is therefore the best explanation people can come up with. String theory tries to tie the quantum aspects together with the space time and forces described by AE. Its only as credible as the information that its based on.
What? Both special and general relativity have been proven over and over again. Special relativity is used on a daily basis for a variety of applications such as GPS, particle accelerators, atomic clocks, etc etc. General relativity has made correct predictions about the orbit of mercury, and gravitational lensing has been directly observed around the sun and distant galaxies. Gravity waves have not yet been directly observed but there is indirect evidence for their existence in the measurements of falling binary stars.
Did you ever read Rational Mysticism ? Because I did, and I found it to be very fascinating, written from a skeptic's viewpoint (as opposed to a cynical skeptic) and he came away with a lot of interpretations that I found intriguing.
Here's to hot beer, cold women, and Glaswegian kisses for all.
Greene's NYT op ed piece perpetuates the silly notion that photons will somehow stop in their tracks and start going backwards due to the accelerating expansion. No they won't, they will just be red shifted further and there will certainly continue to be some asymptotic limit to how far away the furthest galaxies were that we are seeing, but everything we can see now is in a sense in front of the CMB and the CMB will keep coming, no matter how cold it gets.
While it must remain outside the realm of direct observation, I'm more comfortable with the idea of the multiverse as the domain in which physics has evolved through cycles from those Type 1a supernova eggs through some inflating placenta to a next generation Big Bang than I am about any notion that physics is somehow simultaneously testing countless possible variations on its laws. Larger possibility spaces demand smarter exploration techniques.
-- Our systemic servants do not good masters make.
I heard an interview with Greene on the radio last week. He was talking about a junior-level quantum mechanics problem and he said something so wrong my head just about exploded. He said that something fundamentally changes about an electron when you localize it. That what was a probability wave now becomes a point particle. What?!? No it doesn't. It's still a wave that is governed by quantum mechanics. It doesn't suddenly become a point particle governed by Newtonian mechanics.
This long explanation was somehow key to his interpretation of the Many-Worlds theory. He also implied that the many universes of Brane theory and the many universes of the Many-Worlds theory, and other universes due to a Swiss-cheese spacetime are all the same in some unexplained way.
Brian Greene has been out in left field for a long time. Let's build a fence around him and call it a pasture.
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"Greene's book is more theory than fact"?
Just stop it. A theory is built of facts. You are just feeding the 'evolution is just a theory' trolls.
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If you want to get the actual scientific scoop on multiverses, as opposed to John Horgan's myopic rant, check out this excellent article by renowned cosmologist Max Tegmark. It was the cover story in Scientific American a few years ago.
|>ouglas
Never say never. Parts of QM, relativity, evolution and pretty much every other theory we hold dear took much the same criticism until someone figured out clever ways to test them.
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My wife came up with the best multiverse theory I've heard. She said that if there are an infinite number of universes and everything that could happen happens in some universe, then there must be a universe somewhere without (the need for) a multiverse. And if there is one, then it must be the one we're living in. QED: No multiverse
As a physicist, I believe that the many-world interpretation of quantum physics is the best because it is more practical than its competitors.
The first major competitor is the theory that the world is deterministic and its just our lack of knowledge that causes us to perceive a non-deterministic world. The problem with this is that we have no evidence in favor of this proposition and to the extent we have any evidence it is *against* this proposition.
The other major competitor is the theory that the wave function of the whole universe collapses every time we make a measurement. This agrees very well with experiment as long as the person asking the question is the one doing the measurement, but it has a major problem: since wave functions don't collapse unless measured, what counts as a measurement? For example, does collapse only happen when *I* make a measurement? If so, why should I be uniquely privileged? Alternatively, does collapse happen whenever some human being makes a measurement --- that is, if I perform the Schroedinger's cat experiment but with a person instead of a cat inside the box, then has the wave function collapsed even if I never open the box (assuming it is perfectly insulated)?
The advantage of the many-worlds interpretation is that it solves the problem of measurement by *not* treating measurement as being an special-case exception to the rules; it postulates that the wave function of the universe never actually collapses. Given this, how do we make sense of the fact we human beings *do* observe such a collapse? The answer actually appears right in the math: when we demand that a particle in a mix of states tell us which state it is in, it causes us to become entangled with the particle so that a *portion* of the universe splits into two states: one with the particle in the first state and us seeing it in the first state, one with the particle in the second state and us seeing it in the second state, and so on. So from the perspective of each of the observers the wave function has collapsed even though it never did. What happens then if you put an observer in a box and have him or her make a measurement? The answer also appears in the math: although the universe splits inside the box, it does not split outside the box.
This might seem fanciful, but it is something that we can actually test. Although we cannot put human beings in a box for ethical reasons, we can put increasingly large systems in the box that act as "observers" of some particle (by engineering an interaction between the observer and the particle) and then perform interference experiments to determine whether the wave function in the box has collapsed or not. Every such experiment we have performed has shown that the wave function does in fact *not* collapse inside the box but rather splits.
So what is the mathematical difference between being inside the portion of the universe that splits and being outside it? It is simple: if you are outside the portion that splits, then the wave function of the universe can be expressed as a tensor product between you and splitting portion. If you are inside the portion that splits, then this can never be the case.
Thus it turns out that measurement *already falls out of quantum mechanics* in a mathematically rigorous and observer-independent fashion, as long as we are willing to accept that a consequence of this is that from the view of someone external to the universe there is a (mathematically rigorous) sense in which there are multiple copies of you and I within the universe. Sure, if we don't like this consequence we can add a rule that gets rid of it by specifying that the wave-function collapses, but then you have to introduce some arbitrary rule that specified that some macroscopic bodies have the power to cause a collapse but not others. Now in fairness, there do turn out to be mathematically rigorous ways to do this and some of them even provide testable predictions so one of them might be proven correct one day, but there is
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
I knew this would be a problem, once Alexander Luther restored the multiverse during Infinite Crisis. Greene wouldn't have a leg to stand on if the single earth status quo had stayed as it was after Crisis on Infinite Earths. The Antimonitor did us a favor by destroying the multiverse and leaving a single earth.*
*Yes, I realize that a handful of earths survived and were then merged into a single world with a shared history.
But in a parallel universe, you don't don't care about this, so what difference does it make what you say here?
( My objection with multiverses is that the idea of explaining a coin flip by adding a whole extra copy of the universe seems to be a gross violation of Occum's Razor, not to mention conservation of energy )
The main issue is that anyone familiar with the scientific process understands that there is a huge difference between the theory of evolution and string theory. People that learn about science in the wall street journal and the new york times don't understand this. Yes, the fringe of theoretical physics houses some exotic 'theories', but not all theories have the same level of evidence. I really wish that all of science used mathematical terminology, ie. string conjecture, the multi-verse conjecture etc. When something is proven to the extent of plate tectonics or biological evolution, then it should be promoted to theorem. This way, the idiot masses would know that when they read about string conjecture in the wall street journal, it's an idea that scientists are working on, trying to test etc.
It would also put an end to the "it's just a theory" crap when fact and reality run up against the magical fantasy's of two thousand year old Palestinian goat herding desert nomads.
That sounds horribly condescending and dangerous to boot. By saying you need to have an advanced degree in physics to begin to understand this or that theory sounds an awful lot like religious claptrap. Your 'comforting lies' is religious based argument as well. Scientists aren't members of a Priesthood and shouldn't be treated as the only 'Holy Men with the Truth'. And I would say that people who wish to tell someone like Mr. Greene 'To tread carefully' are full of hooey. At least him and a few others are trying to take their knowledge and their theories to the general interested public. Theories and speculation are the name of the game, your game is orthodoxy and staying within the norms of whatever orthodoxy is in fashion at the moment.
Enjoy your Karma, after all you earned it. Feel your Karma Joe, feel it burn.
The "Criticism" was mostly emotionally based, and had very little in the way of "facts". It consists of similar arguments that was used in The Trail of Socrates. If no one ever did rampant speculation we all would have stopped with the Laws of Motion. Newton was good but if Einstein didn't go off and speculate about time our GPS system wouldn't work and we'd just chuck it up to "imprecise measurements" like Newton did with the orbit of Mercury.
SciFicPhy-101 is pure levity field theory for public understanding of many obvious unknowns that ain't no godddd.
Unaccountable leaders are masters, and unrepresented people are slaves. How do US and EU fare?
Saying 'Multiverse Propaganda' is putting a judgment into the description thereby attempting to label the Theory you don't agree with as propaganda. This is Slashdot, not the Rush Limbaugh Comedy Show - most readers here can see that obvious bias and unsubstantiated claptrap on the face of it. It does not advance your argument nor does the 'more theory than fact' quip. It's a Theory dude, sorry if this theory is catching the imagination of people and is getting attention but that's how life goes. All that 'Black Hole' stuff was a theory as well and I do remember the folks whose brains had ossified objecting on much the same lines as you objecting. Very sad, especially when most folks will leave it as theory until something is proven one way or the other so all the ranting and slanted arguments on Slashdot you wish to engage in are pretty much a waste of time.
Enjoy your Karma, after all you earned it. Feel your Karma Joe, feel it burn.
hypothesis, not theory.
How was the universe created?
How will the universe end 2 billion years from now?
Don't care. Don't Care.
How will we prevent environmental devastation of the planet?
How will we find an energy technology that will meet our needs over the next century?
How will we travel into outerspace?
Care!
IMHO, The first set of questions are questions that are good for just providing the science answer to religious question. The second set are actually useful.
Robert Krulwich talked to Brian Greene onstage @ the 92nd St. Y about his Multiverse Theory.
Here it is: http://www.radiolab.org/blogs/radiolab-blog/2008/aug/12/the-multi-universes/
Black holes were predicted to exist in General Relativity, which made many other predictions in other aspects that it made it a very strong theory. Superstring theory is based on, well, a mathematical model that has no confirmation of any kind. M-theory and other like theories are built on superstring theory/theories and thus are not even really theories as the term is used.
Or, to put it simply, your analogy is bullshit.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Wow; proof of multiple universes on Slashdot. The parent comes from a universe where there are still great Scientific American articles.
Every time Shrodinger boxes up another cat, we get a new universe!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
“Those universes either interact or they do not. In the former case they constitute one universe. In the latter case, they are mutually unknowable and therefore certainly irrelevant for science.” -Stanley Jaki
Please take a moment to reflect on that phrase ...
This might seem fanciful, but it is something that we can actually test. Although we cannot put human beings in a box for ethical reasons, we can put increasingly large systems in the box that act as "observers" of some particle (by engineering an interaction between the observer and the particle) and then perform interference experiments to determine whether the wave function in the box has collapsed or not.
I believe that the Many Worlds interpretation and Bohm's interpretation are fundamentally indistinguishable from each other experimentally. In Bohm's interpretation, the wave function also never collapses, but it does push around particles, which turn out to be classical in nature. So, in some sense, Bohm's interpretation is the same thing as the Many Worlds interpretation, only all those worlds exist only as pilot waves to push about the particles in the actual world.
Whether or not many worlds being actual is more true to Occam's Razor than there being an unimaginable number of phantom pilot waves pushing on matter in a single actual world, is left as an exercise for the reader.
|>ouglas
The phantom pilot waves are programmers trying to patch up their bugs before God finds out they F-ed up.
Table-ized A.I.
Still, as other posters have commented, the real reason why (some) physicists are mad, is the seeming giving up on scientific testibility. I think this is wrong - that scientific testibility is possible, in principle and practice, and the ontological benefits of a Mulitverse are worth it. I could recommend David Deutcsh's book "Fabric of Reality" for an excellent discussion, or my own book "Theory of Nothing" (gratutitous plug warning).
There are two theories:
(1) The Earth is a planet, more or less like any other planet in the universe. It's just the one that we happen to live on.
(2) The Earth is the center of the universe, and the laws of motion and gravity are extremely complicated.
Most people don't realize this, but the details for #2 can be worked out; it's just that we reject this theory by Occam's Razor. There is, however, absolutely no way to experimentally determine whether theory #1 or theory #2 is the correct one.
The theory of multiverses is like theory #1. It makes our theories simpler, and makes us less in the center of things. If John Horgan must assert that theories of multiverses are a moral outrage, then he must also assert that theory #1 is a moral outrage. The Earth is the center of the universe after all.
|>ouglas
P.S. I just pwned that guy.
From TFA:
Sheesh. So, 9/11 and global warming caused you to lose your sense of wonder about the possible nature of the Universe? I hope the fuck I never become *you* when I get old.
...does collapse only happen when *I* make a measurement? If so, why should I be uniquely privileged?
"Thou art god"?
Gotta admit, I didnt find the criticism any particularly more worthy than the speculation.
multiverse cannot be science
a lot of the stuff you take as 'science' today, were ridicule of earlier centuries. there were people saying similar things like you.
moreover, among them there were a lot of the science establishment doing that. on top of it, a lot of it was done to the science pioneers you acknowledge as great today. last, but most importantly, its not a phenomenon that was centuries ago - it is happening frequently, like even in the past decade :
http://amasci.com/weird/vindac.html
read excerpt in the link, then scroll down (way down) to see which particular great scientist was ridiculed for what. and even called a charlatan. and, most importantly, by whom.
like
Binning/Roher/Gimzewski (scanning-tunneling microscope)
Invented in 1982, other surface scientists refused to believe that atom-scale resolution was possible, and demonstrations of the STM in 1985 were still met by hostility, shouts, and laughter from the specialists in the microscopy field. Its discoverers won the Nobel prize in 1986, which went far in forcing an unusually rapid change in the attitude of colleagues
the MORONS who ridiculed these people, are still deans, dept. heads around the world in various important universities and corporations .... imagine ...
Read radical news here
It really bugs me that most of the scientists to catch the media spotlight in the last decade or so have been lame ducks like this one. I don't think there's anything wrong with theoretical physicists, but the weird "gee-whiz" science they practice is no real representation of science. It gives the impression that the only way to capture the public's attention is to make up bizarre theories that have no real use. Every time I hear someone like Greene talk, it sounds suspiciously like the "what if we're all, like, one atom on like a giant's thumbnail or something!?" brand of stoner bullshit you would hear from a liberal arts major who took an astronomy class once. Scientists from Kaku to Tyson who promote the "Wowzers" school of scientific thought tend to be hopeless, mincing jackasses at best and ourtight charlatans at worst.
Science has not only the potential, but the duty to ask profound questions about human enterprise and provide meaningful answers. Positing the most outlandish theories you can and spoon-feeding a kindergarten version of them to a public which doesn't have the time to know better is probably the reason that pubic attitudes towards science are so shitty lately.
Scientists need to take very seriously the public face they present, and realize that the kind of science they give people is the kind of science they will perform. No one since Sagan has made a serious attempt to get people interested in real science and to provide them with the tools they might need to reap its very real rewards. Instead we're given junk food like Greene's book which uses concepts we don't understand to fool us into thinking things that aren't true. The first step towards correcting this is to stop presenting the surface facts of a scientific advance without paying attention to the theoretical underpinnings: quantum mechanics is an excellent example of something that shouldn't be taught to anyone without at least three semesters of calculus, because then we get Deepak Chopra and homeopathy. The media is usually given the blame for seizing on a piece of misinformation, but scientific media darlings ladle stuff like this out with rabid glee.
Point is, stop it. I'd bet good money that scientific illiteracy is traceable back to scientific showmanship like this multiverse crap. Science is a process which has as its goal the separation of reality from unreality, and when you start positing the existence of magic, unicorns, and voodoo like this stuff the whole damn thing falls apart.
Regardless, The Elegant Universe will be 90% wrong, the movie is much more bearable than the book, it is almost pure conjecture.
Hey buddy, can i bum a karma? ~}CinderellaManson{~
I thought decoherence was the proposed resolution to the measurement->collapsing wave function approach of interpreting QM. Has this been derailed?
Alternatively, I've seen a proposal that QM is just a probability algorithm correlating various observables, as in http://arxiv.org/abs/quant-ph/0412182
"Politicians and diapers must be changed often, and for the same reason."
"Multiverse theories don't turn me on anymore. Perhaps it's because of 9/11 and all its bloody consequences, especially the U.S. wars in Afghanistan and Iraq."
yes, this is an actual quote from the article.
Every such experiment we have performed has shown that the wave function does in fact *not* collapse inside the box but rather splits.
You could also argue from this that the wave function of the apparatus inside the box is entangled with the particle it's measuring, and doesn't collapse until we open the box. That's what Schrodinger's thought experiment with the cat was about, right?
I agree with you that we should be looking for testable differences betweeh the competing theories ... but I don't think this is one.
I read the first couple of paragraphs of the first linked article that establish the presence of a lack of scientific evidence for the many worlds theory. Although i am not a huge proponent of this worldview I consider it as likely as any other out there right now. The author of the first scientific american article linked in this story states that this article is based upon science fiction. This a a patently false statement that is either very ignorant of the facts, or a purposeful falsehood. The multi slit experiment which shows the effect of multiply uncollapsed photons through a slit wide enough for just one photon is a repeatable, measurable effect which caused this theory to be articulated. It was not a fanciful conjecture meant to enrich the author, but in fact an attempt to explain observable phenomena that was unsettling to both the scientist involved in the measurement, and those who reviewed the findings. The fact that the author of this article and the poster start off with this perspective towards observable science gives me great doubt to both their objectivity and ability to understand observable, reproducible phenomena.
Radio National (Australia) has podcasts of The science show", Robyn Williams has been it's host for about 30yrs and IMHO is the best science journalist on the planet.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
"Greene's book is more theory than fact." Er, WTF?
I think you meant to say Greene's book is more conjecture than fact. Facts are things that we observe. They are the what. And of course, there are no observations of other universes at this time, let alone a multitude of them. Theories explain the why or how. We observe gravity. Gravity is a fact. There are various theories that attempt to explain gravity in terms of how it works and why. Theories are hypotheses that have been tested and confirmed experimentally. Obviously there are no theories regarding multi-verses because we haven't observed any and we haven't put any of our explanations to the test.
A defense that this is not pseudo-science is laughable. I have no problem with speculation of this sort as it may one day lead to a real science. BUT, and this is important: If you call this science, then you must also allow creationist ideas about the origin of the universe and life into these discussions. You can't have it both ways.
I find Scientific American guy's moralizing immoral. The book is an explanation of the different kind of multiverse theories which are present in current theoretical physics. The guy seems to have a problem with the fact that Greene and the rest of us scientists should be obligated to spend our time solving humanities ills. If he really thought that was so immoral to be thinking about and communicating true facts about possibilities which arise in theoretical physics rather than solving the Problems of Humanity, then surely it is also immoral to be thinking about and communicating opinions of the prior. Surely we should all be studying cancer. Also, the guy really mentions Karl Popper, which goes to show how much he has thought about the philosophy of science.
For anyone else who is similarly repelled by Mr. Horgan's myopic rant, I would also recommend looking at David Deutsch's excellent (and quirky) The Fabric of Reality, which includes the Everett-Wheeler type of multiverse as Deutsch discusses quantum computing.
Now a lot of commenters have jumped in with "... but this stuff is all unfalsifiable...", which Deutsch explicitly addresses, pointing out that if algorithms such as Shor's or Grover's work, they point fairly clearly to a multiverse, otherwise where is the algorithm actually solved?
A very interesting read, imho.
The problem with Einstein theory at the time was that technologically it was not feasible, at the time. But not impossible. The problem with Everett#s itnerpretation 8note that I did not say theory) and all the manifold multiverse theory is that they are not falsifiable, because *ALL* include a cope out that NO UNIVERSE CAN COMMUNICATE WITH ANOTHER. That make it impossible to test , not falsifiable and thus NOT A THEORY. So not that i am finished to yell my frustration, you can understand why people are P.O. that the multiverse stuff get traction.
Folks multiverse are stuff of star trek and DC comic book. Not of physic.
And yes, to answer another poster below the thread branch "no it is not better than Deepak choprah, and no it is not jealousy, it is frustration that only imaginative speculation get traction in general media".
Don't forget frame dragging and pretty weird GR effect. In fact about the only thing missing is gravity waves. Even Einstein said they are probably too weak to ever detect.
The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
I agree, it is not a scientific hypothesis if it cannot be tested. But the fact that something cannot be tested at our current level of science and technology, doesn't necessarily mean that (a) it isn't true, and (b) it cannot be tested at some point in the distant future.
Democritus of ancient Greece hypothesized that everything in the world consists of particles, and constructed the first (as far as I know) coherent atomic theory. But at that point, the hypothesis seemed untestable - and lost to the theory of the elements, which from their point of view was backed by experimental observations (burn something, and you get vapor (water), smoke ("air"), ashes ("earth"), and fire.) That doesn't mean that Democritus' theory was wrong or actually untestable, it just seemed so at the time.
100% agree. At last, the concept of multiverse is gaining acceptance in the scientific community and in general public (well, the part interested in science).
It should have occurred a long time ago, with Everett theory. People were blinded with the idea of "interpretations" of quantum physic having equal value. Epistemologists were too happy to get rid of philosophical realism, driven by first quantum physic understandings. They didn't reconsider this position after Everett theory.
I heard Greene's interview on Fresh Air and it seems like he does a good job of explaining the theory and the controversy surrounding it, emphasizing that it is the most reasonable explanation he is aware of without yet being entirely convincing.
That said, I studied math and physics at Columbia, and have heard many stories about Greene. My best friend there took his mathematical physics course. And Brian Greene is pretty much universally described as an arrogant jerk. Even by Columbia standards.
It is a case of, fairly well respected theorist makes a name for himself doing pop-sci stuff, gets offered tenure in TWO departments and comes to think of himself as hot shit, then gets pissed off when because of his notoriety he has to teach courses to packed classrooms. So he would do his very best to get everyone to drop his course.
My friend got so pissed off after the first day that he never showed up to a single lecture, studied his ass off without having to listen to the guy talk, and aced the final!
There is a more fundamental problem: there is no "we".
To any given subjective human, the only evidence of the current universe existing is their first-hand experience of it. So for instance, the only evidence for you that this universe "exists" (whereas the universe of Conway's Game of Life, or of that game of Quake you just played, or any other mathematical universe, does not actually "exist") is that you are observing being within it. Quite clearly, at any given split, you do not experience being in the "other" universes. This puts them in the same bucket as that Game of Life, Quake, or whatever -- mathematically they are lovely but to any observer/reasoner they cannot be said to "exist" because you cannot be within them. The thought that somebody else or some other you might be experiencing the other universe is neither here nor there -- even if you'd like to think of an infinite succession of "you" splitting off from yourself at every moment, you cannot experience being those other people or other selves and as such cannot observe evidence of any universe existing except this one. Or to put it another way, for all observers other universes "really existing" is identical to other universes "really not existing".
(The "split" versus "collapse" within the box is neither here nor there: that split or collapse still always appears to occur within the physics of the observer's universe, and as such still only 1 universe is ever observed or can ever be observed.)
So if "an infinite number of universes exist" is essentially identical to "actually, no they don't", then that infinite number of universes does rather look like that imaginary teaset in space... The argument that it makes the equations simpler (so you don't have to consider special cases) doesn't pass muster -- it would make the equations much simpler to pretend that God created the universe this instant, all the experiments are just fake memories, and so there's no such thing as physics in the first place, but that tends not to be considered good science!
To answer your own question -- "does collapse only happen when *I* make a measurement? If so, why should I be uniquely privileged?" -- for all values of "you", "you" (the observer/reasoner) must be uniquely privileged because you are the only person that can empirically declare that anything exists at all.
Sorry to segue into philosophy, but when you're talking about matters of what it means to exist, it usually does come back to St Augustine / Descartes. ("Even if I am mistaken, I am" and "I think [observe] theferfore I am". If those other universes are provably unreachable from that declaration of existence then there is no difference from their non-existence.)
I haven't commented on slashdot in a long while, but this post should never have made it frontpage.
Having read both Greene's op-ed piece on the NY Times, and John Horgan's article, I find the latter much more questionable. Horgan criticizes multiverse theories on purely subjective grounds, and basically thinks that science nowadays should care about real issues first, something no serious scientific researcher would ever support.
Greene's op-ed article is a very good vulgarisation of theoritical physics, I have to wonder what is wrong with it. Seems like the poster has a big chip on his shoulder against Greene for some reason.
I think he is making a valid - if not brave - point. And probably hoping for some support from his readership.
Multiverse Theory opens the possibility of "happy endings" in the style of Sliding Doors or the afterlife: although this existence is not perfect there is another world where it is/will be. We can't do much about this one, sorry for the inconvenience.
This is a very nice explanation of the different interpretations of Quantum Mechanics. However, there are two big problems an interpretation has to solve, one of which is the measurement problem, which is what the Many Worlds interpretation was invented to solve. The other problem is the completeness problem. This is a problem that was raised by Einstein, Podolsky and Rosen in their thought experiment of 1935. They wanted to show that the wave function could not be a complete description of reality. Von Neumann attempted to prove that any addition to QM - so called hidden variables - could not reproduce the experimental results of QM. But John Bell showed that Von Neumann had made a mistake (he failed to take into account the fact that measurement disturbs microscopic systems). Bell went on to show that only a non-local theory could introduce hidden variables into QM and reproduce its experimental success. As it happens, David Bohm had already created such a theory, based on the de Broglie interpretation.
Although Physicists like the Many Worlds interpretation, philosophers hate it. They all much prefer the Bohm interpretation, usually called a statistical interpretation of QM. Da Cog correctly describes this as a deterministic interpretation. The wave function represents what we know of the state of the QM system. Naturally it collapses if we know something new. Naturally, in a closed unmeasured system, it doesn't collapse. For philosophers this is a compelling interpretation. However, for physicists it is not compelling because it complicates the maths. So the choice, unless an experiment can be done to decide between them, is between an interpretation that is ontologically extravagant but mathematically elegant on the one hand, and an interpretation that is ontologically elegant but mathematically complex on the other.
Can you recommend a book for laypeople explaining this many-worlds view in more lenght?
http://barrapunto.com/ - News for nerds, en español
religion and mythology, both of which can also never be proven or disproven.
The difference is that mythology does not pretend to be true, any more than Shakespeare's Hamlet is real, whereas religion claims to be actually true.
To have a right to do a thing is not at all the same as to be right in doing it
the so called Multiverse theory is a perfectly valid intpretation of quantum mechanics. Its not new. it was first clearly stated by Everett
In the fifties and sixties.The interpretation of this theory as parallel universes in the sense of science fiction, that is the realm of dumbasses that pass themselves as american journalists
Claims that directly contradict reality are necessarily disproven by their contradictory nature. All claims to a "God", when described in sufficient detail, contain some contradictory component, disproving the claim. For example, God the "creator being who spawned existence", would be a consciousness *conscious of only itself*, existing in *non-existence*, acting *outside of time*. That is contradictory on three counts.
The wave function is a *concept of method* used to aid the mind in understanding reality. The fact that it conveniently and easily predicts reality does not imply there is anything *physical* about the wave function, any more than the use of complex numbers to calculate phase shift in electrical circuits, or the use of "electron holes" to simplify equations, implies the actual physical existence of imaginary numbers or "electron holes".
As for the apparently strange fact that observation affects reality - that is simply due to the fact that we must bounce particles off of something in order for us to measure it. To *see* electrons going through the double-slit experiment, we have to bounce photons off of them - and that interferes with the experiment, changing the result. It has nothing to do with us being "entangled observers" or having some "privileged reference frame".
I recommend Richard Feynman's 1-hour lecture on the quantum mechanical view of nature, which clarifies much of the poor philosophizing that has come out of quantum mechanics.
Niel Stephenson's most recent "Anathem" uses the multiple-worlds interpretation in a new and interesting way...
but scientifically (philosophically?) I think it's all blather -- see this link for something
that is mathematically consistent and philosophically much less indigestible...
http://en.wikipedia.org/wiki/Transactional_interpretation
God...so many of the academia have become the idiots they want to educate. You can't come up with a theory that says theirs is wrong, because if you do, you are wrong. I thought Scientist were supposed to be the greatest failures, because out of their failures comes their successes. Closed minds: found at a university, as a professor or scientist, who can't think their way out of their mindless boxes.
I still need to finish watching season 5 of "Sliders".
UNIX: Find it, fsck it, forget it.
Sure. So what? If you don't want conjecture then read a textbook on relativity. A lot of people like to get glimpses of the bleeding edge, not the tested-for-the-last-century edge.
"Bearable" is entirely your own bias.
As for the apparently strange fact that observation affects reality - that is simply due to the fact that we must bounce particles off of something in order for us to measure it. To *see* electrons going through the double-slit experiment, we have to bounce photons off of them - and that interferes with the experiment, changing the result. It has nothing to do with us being "entangled observers" or having some "privileged reference frame".
That is completely wrong. The reason why measurement affects reality is because of the No-Cloning Theorem which dictates that quantum information cannot be copied, so the most that you can do is entangle yourself with the particle which creates the perception of a collapsing wave function. This is not philosophy, this is mathematics.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
I wish I had one for you, but unfortunately I don't read physics books for laypeople any more so I don't know whats out there.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Although Physicists like the Many Worlds interpretation, philosophers hate it. They all much prefer the Bohm interpretation, usually called a statistical interpretation of QM. Da Cog correctly describes this as a deterministic interpretation. The wave function represents what we know of the state of the QM system. Naturally it collapses if we know something new. Naturally, in a closed unmeasured system, it doesn't collapse. For philosophers this is a compelling interpretation. However, for physicists it is not compelling because it complicates the maths. So the choice, unless an experiment can be done to decide between them, is between an interpretation that is ontologically extravagant but mathematically elegant on the one hand, and an interpretation that is ontologically elegant but mathematically complex on the other.
That is a very good summary of the situation. Personally as a physicist I don't see the assumption of many worlds as being ontologically extravagant --- especially since there aren't really many worlds, there is just one quantum world that contains what *we* as classical creatures would consider to be multiple parallel realities --- but it does drive philosophers crazy. :-)
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Every such experiment we have performed has shown that the wave function does in fact *not* collapse inside the box but rather splits.
You could also argue from this that the wave function of the apparatus inside the box is entangled with the particle it's measuring, and doesn't collapse until we open the box. That's what Schrodinger's thought experiment with the cat was about, right?
The key is that you can do experiments that tell you whether the state inside the box has collapsed or not without measuring the state itself, which is different from Schroedinger's thought experiment in which you do measure the state inside the box.
In fact, a variant of this principle is used in something called quantum error correction (which is one of the subfields in which I do research), where you can measure and correct error in an encoded quantum bit without ever measuring the bit itself.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Nonetheless, the fact remains that *I* as a subjective human being can do experiments to determine whether I am the only one who can collapse wave functions or whether other human beings do so as well. That is, this distinction does not require the assumption that a objective reality exists, only that I be able to distinguish between two different kinds of patterns that I perceive.
Furthermore, while it is technically true that there is no reason not to believe that I am a privileged being in this universe and so the rules apply different to me than to other entities, models where I do not make this assumption have historically tended to be better descriptions of my perceptions than those where I do make this assumption.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
I thought decoherence was the proposed resolution to the measurement->collapsing wave function approach of interpreting QM. Has this been derailed?
No, actually in retrospect I see now that quantum decoherance exactly corresponds to the model that I described, its just that it had never been explained clearly to me so I thought it was referring to something else. (Ironically the wikipedia article I just looked at now was in many ways clearer than the explanation I'd received in my classes, though in fairness it might just be that I have a few more years of experience under my belt so that it makes more sense to me now!)
Anyway, so in short you are absolutely right, and I appreciate you asking this question because it caused me to learn something. :-)
Alternatively, I've seen a proposal that QM is just a probability algorithm correlating various observables, as in http://arxiv.org/abs/quant-ph/0412182
Hmm, interesting, I am not familiar with that result, but it might answer a question that is left-open by the many-world interpretation: why is it that the square of the amplitude of a component in the wave function corresponds to the probability of measuring it in that state?
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Darn it! I knew I should have ditched Unix for Multix years ago so I can talk to my other selves in other Universes!!!!!
Sure enough, the cow costume was hanging up next to the superhero outfit and sailors uniform. (S,Spud)
That is completely wrong...This is not philosophy, this is mathematics.
That is not an argument. Why is it completely wrong? And why is Richard Feynman incorrect for espousing it? And why is it so obvious from perception?
The reason why measurement affects reality is because of the No-Cloning Theorem which dictates that quantum information cannot be copied, so the most that you can do is entangle yourself with the particle which creates the perception of a collapsing wave function.
This is as backwards as saying that "the amount of impedence of the individual components of an AC circuit is caused by the imaginary exponential." No, the imaginary exponential was devised to easily calculate the impedence. To pretend that the math makes reality is to put the cart before the horse. Quantum mechanics and the no-cloning theorem are concepts used for predicting reality. They are concepts of method. They do not create reality.
That is completely wrong...This is not philosophy, this is mathematics.
That is not an argument. Why is it completely wrong? And why is Richard Feynman incorrect for espousing it? And why is it so obvious from perception?
Sure, I will grant you that if you cut my explanation from a quote then it does sound like I did not make an argument.
The point is that although it is true that we need to interact with the system in order to measure it, it is not obvious that this should specifically cause the wave function to collapse. Thus, the explanation you gave is not sufficient to understand why the wave function collapses. By contrast, the No-Cloning theorem does provide a sufficient explanation.
Feynman was most likely giving an approximation of what was going on for the ears of non-physicists and so one should be wary about reading into it too literally.
Finally, I have never claimed that the No-Cloning theorem was the obvious explanation for wave function collapse; in truth, there is little that is immediately obvious about quantum mechanics.
The reason why measurement affects reality is because of the No-Cloning Theorem which dictates that quantum information cannot be copied, so the most that you can do is entangle yourself with the particle which creates the perception of a collapsing wave function.
This is as backwards as saying that "the amount of impedence of the individual components of an AC circuit is caused by the imaginary exponential." No, the imaginary exponential was devised to easily calculate the impedence. To pretend that the math makes reality is to put the cart before the horse. Quantum mechanics and the no-cloning theorem are concepts used for predicting reality. They are concepts of method. They do not create reality.
Sure, but the model you outlined with particles bouncing is also just a model of reality rather than being reality itself, so you can't claim that the problem with my explanation is that unlike you I invoke a model to explain what is happening.
Snarkiness is inversely proportional to wisdom because it emphasizes feeling right rather than being right.
Sure, I will grant you that if you cut my explanation from a quote then it does sound like I did not make an argument.
Your explanation is not an *argument* against my explanation, that was why I cut it out. The only parts of your reply that actually responded to my explanation were the first and last sentences. I simply pointed out that they did not represent an argument.
Thus, the explanation you gave is not sufficient to understand why the wave function collapses. By contrast, the No-Cloning theorem does provide a sufficient explanation.
The no-cloning theorem is a more precise *predictor* of reality than "particles bouncing off eachother", but it is also more abstract, and not necessary for explanation to a layman. To explain why observing the double-slit experiment changes the result, it is only necessary to say, "the light that is required for one to make an observation happens to interact with the entities one is trying to observe, and that interaction changes the result." That removes the mystery regarding the role of the observer. If they then ask, "how does light interact with electrons", then you would have to get into the more abstract discussion.
Explanation as path to understanding involves delving into deeper and deeper layers of abstraction. If I were ask how fish breathe underwater, and you started at the quantum mechanical level, you would not be *explaining* anything to me that I could understand and conceptually integrate, because you would not be connecting it to my existing knowledge. You would first have to discuss the biological, then the chemical, etc. It is not wrong to answer, "because they have gills". Likewise, "light interacts with electrons, changing the result" is not a wrong answer to the question above.
The Many Worlds Interpretation (MWI) is a legit possibility, and in fact, one of the more promising interpretations of quantum mechanics out there. Many people misunderstand it though, thinking every choice or possibility somehow "creates" a whole other somewhere that we can possibly travel to ala Star Trek with evil twins.
MWI is in fact much simpler than that. Think of the universe as a giant quantum computer. Quantum computers can perform many computations in parallel. In fact, MWI says nothing less than that each branching point triggers a new parallel computation, specifically, the universe exists entirely in a state of superposition each of which was triggered by a branch in the past. Metaphysically, there is nothing more and nothing less than the wavefunction.
That's pretty compelling IMO. It's probably metaphysically the interpretation of QM with the fewest assumptions, so by Occam's razor, it's preferable to most other interpretations.
Higher Logics: where programming meets science.
So Terry Pratchett was right all along. Somehow, I knew it.