# "What the Bleep Do We Know? **URL:** \ **Category:** Factual Questions\ **Created:** [August 11, 2006, 9:12pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356 "2006-08-11T21:12:44Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![zbegniew](https://avatars.discourse-cdn.com/v4/letter/z/ecae2f/32.png) [@zbegniew](https://boards.straightdope.com/u/zbegniew)\ **Post date:** [August 11, 2006, 9:12pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/1 "2006-08-11T21:12:44Z")
I’m pretty sure the POV expressed in the movie was about a light year out in front of the facts, but I would like some learned person to tell me if this is true. It seems that in the world of Quantum Mechanics, the position of a particle is expressed as a set of probabilities that it will be in a given place. But it can’t be said to be in any particular place until it’s observed. Then, and only then, does it “lock in” to a particular location. This imples that observation is somehow necessary to create reality, at least at the quantum level. This is sometimes referred to as “The Measurement Problem” or “The Observer Problem.” The makers of the movie take this to mean that there is no physical reality apart from an observer. So not only does a tree falling in an unhabited forest not make a noise, there is no tree and no forest until someone is there to observe it. WTF? ---
**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\ **Post date:** [August 11, 2006, 9:25pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/2 "2006-08-11T21:25:27Z")
This has been discussed before, here’s one thread: [http://boards.straightdope.com/sdmb/showthread.php?t=353290&highlight=bleep](http://boards.straightdope.com/sdmb/showthread.php?t=353290&highlight=bleep) Everything I’ve read about the movie (never saw it, although Marlee Matlin is a relative on my mom’s side) is that it’s basically a load of hooey. ---
**Author:** ![CynicalGabe](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@CynicalGabe](https://boards.straightdope.com/u/CynicalGabe)\ **Post date:** [August 11, 2006, 9:30pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/3 "2006-08-11T21:30:11Z")
[QUOTE=Valgard] This has been discussed before, here’s one thread: [http://boards.straightdope.com/sdmb/showthread.php?t=353290&highlight=bleep](http://boards.straightdope.com/sdmb/showthread.php?t=353290&highlight=bleep) Everything I’ve read about the movie (never saw it, although Marlee Matlin is a relative on my mom’s side) is that it’s basically a load of hooey. [/QUOTE] Ditto. If you want to hear the story without paying to see the movie, go sit in a hippie coffee shop and listen to a bunch of stoners talk about the universe. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 11, 2006, 9:40pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/4 "2006-08-11T21:40:04Z")
I don’t see the quantum question discussed in the linked thread, although it may be in one of the even earlier ones. The observer problem comes from one interpretation of the equations of quantum mechanics, usually called the Copenhagen Interpretation. It’s actually the one that is the _least_ at odds with common sense understanding of the universe. However, there are mathematically equivalent formulations of the equations that remove the observer problem entirely. And many physicists have shown that a human observer is not necessary for macroscopic (i.e. larger than quantum-sized) objects to exist in the common sense way we’re used to. The whole thing boils down to a particular philosophical viewpoint, one that can be questioned or challenged in numerous ways. The filmmaker apparently liked to use the most “Gosh WOW” argument, figuring that would be the best way to blow peoples’ minds. Almost nobody in the scientific community much cares for this interpretation, or spends any real time thinking about it. The few who do tend to reject it entirely. Certainly, the rest of us can safely ignore it at all times during our lives. ---
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [August 11, 2006, 9:55pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/5 "2006-08-11T21:55:52Z")
[QUOTE=Exapno Mapcase] The observer problem comes from one interpretation of the equations of quantum mechanics, usually called the Copenhagen Interpretation. It’s actually the one that is the _least_ at odds with common sense understanding of the universe. [/QUOTE] While I agree with the rest of your post, I’m left wondering why you feel that the CI is the interpretation “least at odds with common sense understanding of the universe.” IANAP, but from my reading, not only is the CI is now widely held to be obsolete (at least outside beginning quantum physics courses), it is the one _ **most** _ at odds with common sense. For one thing, it is non-deterministic (a wildly counter-intuitive property) while many if not most other interpretations these days are deterministic. Then, there is the measurement problem at issue here in this thread, which is only a problem (to my knowledge) for CI. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 11, 2006, 10:18pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/6 "2006-08-11T22:18:45Z")
What are the challengers? The main one is the Everett many-worlds interpretation, which requires an infinite number of complete universes splitting off with every determination of a quantum variable. My understanding is that it’s even less accepted by physicists than the Copenhagen Interpretation and the philosophical arguments are even more stretched. Other interpretations can be found on [Wiki](http://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics) and all have weirdnesses so great that most of them are accepted by the originator and not many others. I don’t think that the Copenhagen interpretation is obsolete, although one of the physics gurus can correct me. It’s still probably the popular and widely used, and that means that more people have tinkered with it to smooth out more of the rough edges. You cannot correct it to have determinism, though, without creating other problems from a common sense viewpoint. The universe really does appear at base to be counterintuitive from any human standpoint or interpretation of it. ---
**Author:** ![groman](https://avatars.discourse-cdn.com/v4/letter/g/73ab20/32.png) [@groman](https://boards.straightdope.com/u/groman)\ **Post date:** [August 11, 2006, 10:56pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/7 "2006-08-11T22:56:58Z")
[QUOTE=ambushed] IANAP, but from my reading, not only is the CI is now widely held to be obsolete (at least outside beginning quantum physics courses), it is the one _ **most** _ at odds with common sense. For one thing, it is non-deterministic (a wildly counter-intuitive property) while many if not most other interpretations these days are deterministic. Then, there is the measurement problem at issue here in this thread, which is only a problem (to my knowledge) for CI. [/QUOTE] I don’t know,I think it’s the most obvious thing. It’s even reflected in our speech. Velocity is defined as rate of change of position over a period time. Location is defined as position at a point in time. You can’t have a period of time and a point of time at the same damn time. For any given time point, the lack of precision provides an interval and not an infinitely small point. For example, 5 seconds from now is the interval between 4.75 to 5.25s from now if we’re using 1/4 second resolution. That time interval would have a change in position during it, and the bigger the time interval the more precisely can we define the objects momentum over that time period and less precisely can we define the objects position. So the precision in the time point at which you define “position” of something is inversely proportional to the precision of its momentum. I think “measurement” is a really poor choice of words. The object simply would have 0 precision in its momentum (not the measurement of the momentum) for any given absolute position. Heisenberg just put a hard limit on that. ---
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [August 12, 2006, 5:32am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/8 "2006-08-12T05:32:10Z")
**groman** , I don’t understand what point you’re making. ---
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [August 12, 2006, 6:42am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/9 "2006-08-12T06:42:48Z")
First, **Exapno Mapcase** , I must say it seems to me that you haven’t really answered the question regarding why you feel CI is the _ **least** _ bizarre interpretation. I still say that if it is not _the_ **most** , then it is certainly among the very few most bizarre. After all, CI insists consciousness is an **essential** ingredient in quantum physics and that your mind actually controls what happens, which is _supremely_ outlandish and is really just too absurd for modern minds outside of crackpots like Gary Zukav of _The Dancing Wu Li Masters_ infamy. For example, it essentially suggests that the moon does not truly exist when no one is looking at it and gives considerable credence for the absurd Berkeleyian view and his proof of the existence of God! Many people don’t seem to realize it, but Schroedinger’s cat was actually an utterly compelling _reductio ad absurdum_ argument against the Copenhagen interpretation. [QUOTE=Exapno Mapcase] What are the challengers? The main one is the Everett many-worlds interpretation, which requires an infinite number of complete universes splitting off with every determination of a quantum variable. My understanding is that it’s even less accepted by physicists than the Copenhagen Interpretation and the philosophical arguments are even more stretched. Other interpretations can be found on [Wiki](http://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics) and all have weirdnesses so great that most of them are accepted by the originator and not many others. [/QUOTE] Most of what I have read tends to contradict your thesis regarding the popularity of CI, at least for younger physicists. For one thing, by far the most popular “interpretation” is actually a refusal to interpret QM at all (see: [The shut up and calculate interpretation](http://www.mtnmath.com/faq/meas-qm-6.html)). Yet there appears to be a strong correlation between the “shut up” view and CI. As for those who can’t ignore the epistemological and other problems and thus actually hold an interpretation, one form or another of the many-worlds interpretations are held by the strong majority of more modern/younger physicists (for better or worse; I personally don’t like it all that much either). But I don’t think there can be **any** reasonable doubt that an interpretation that excludes Berkeleyian popping in and out of existence or between states depending on a mind’s whim is _vastly_ less bizarre and more rational and comprehensible than the laughably freakish Copenhagen view. I kind of like Bohm’s implicate order, myself, even though nonlocality and its relativity violation bothers the hell out of me (but I’d rather give up locality than determinism and realism). The CI is, among the younger experts, comatose if not completely dead from what I’ve been given to understand from my reading. You just don’t find many newly minted QM doctorates laboring under the old-fashioned and extremely counter-intuitive concepts of CI (but I freely admit you find effectively _zero_ Bohmians). [QUOTE=Exapno Mapcase] The universe really does appear at base to be counterintuitive from any human standpoint or interpretation of it. [/QUOTE] It’s my view that quantum weirdness arises from the fact that we cannot (yet?) model what’s really happening because we cannot _know_ what’s happening. But I don’t think QM is _necessarily_ counterintuitive, especially given that locality has already been shown to be probably the weakest link in the “pick only two of three” triad of locality, determinism, and realism. So why not abandon locality along with the absurdity of Copenhagen and limit your choices to those interpretations that demand both realism and determinism? That would leave you with far more intuitive options. ---
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [August 12, 2006, 7:00am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/10 "2006-08-12T07:00:04Z")
Also, regarding the popularity of MWI, see: [The Many-Worlds FAQ](http://www.anthropic-principle.com/preprints/manyworlds.html) from which I will now quote: > [@](#): > > “Political scientist” L David Raub reports a poll of 72 of the “leading > cosmologists and other quantum field theorists” about the “Many-Worlds > Interpretation” and gives the following response breakdown [T]. > > 1. “Yes, I think MWI is true” 58% > 2. “No, I don’t accept MWI” 18% > 3. “Maybe it’s true but I’m not yet convinced” 13% > 4. “I have no opinion one way or the other” 11% > > Amongst the “Yes, I think MWI is true” crowd listed are Stephen Hawking > and Nobel Laureates Murray Gell-Mann and Richard Feynman. Gell-Mann and > Hawking recorded reservations with the name “many-worlds”, but not with > the theory’s content. Nobel Laureate Steven Weinberg is also mentioned > as a many-worlder, although the suggestion is not when the poll was > conducted, presumably before 1988 (when Feynman died). The only “No, > I don’t accept MWI” named is Penrose. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 12, 2006, 5:13pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/11 "2006-08-12T17:13:57Z")
[QUOTE=ambushed] For example, it essentially suggests that the moon does not truly exist when no one is looking at it and gives considerable credence for the absurd Berkeleyian view and his proof of the existence of God! [/quote] No it doesn’t and no it doesn’t. The moon is not there if you don’t look at it nonsense has long been abandoned by physicists, including those who use CI. > [@](#): > > It’s my view that quantum weirdness arises from the fact that we cannot (yet?) model what’s really happening because we cannot _know_ what’s happening. But I don’t think QM is _necessarily_ counterintuitive, especially given that locality has already been shown to be probably the weakest link in the “pick only two of three” triad of locality, determinism, and realism. So why not abandon locality along with the absurdity of Copenhagen and limit your choices to those interpretations that demand both realism and determinism? That would leave you with far more intuitive options. I disagree. All the larger theories that marry QM and relativity will still have elements that are counterintuitive weirdnesses. Our sense of what _should_ be is too limited to work at the very large and very small. For that matter, we can’t even agree on what is intuitive and what isn’t. I prefer to leave this to the philosophy majors. As long as all the interpretations are mathematically equivalent I agree with those who say that philosophizing about things we’ll never be able to touch and measure is an irrelevancy. And I believe that the universe is really there all the time, and does not depend on any definition of consciousness. But I don’t think that is incompatible with CI either. Beyond that I’m not competent to comment, so I think I’ll let it go at that. ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [August 12, 2006, 8:36pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/12 "2006-08-12T20:36:47Z")
> [@](#): > > 1. “No, I don’t accept MWI” 18%[…] > The only “No, I don’t accept MWI” named is Penrose. So, one guy is 18% of 72 people? I don’t get it… ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [August 12, 2006, 8:37pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/13 "2006-08-12T20:37:48Z")
[QUOTE=DrCube] So, one guy is 18% of 72 people? I don’t get it… [/QUOTE] Man, I’m a moron. He’s the only one named. Sorry. ---
**Author:** ![DanBlather](https://avatars.discourse-cdn.com/v4/letter/d/f4b2a3/32.png) [@DanBlather](https://boards.straightdope.com/u/DanBlather)\ **Post date:** [August 13, 2006, 4:35am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/14 "2006-08-13T04:35:47Z")
[QUOTE=Valgard] Everything I’ve read about the movie (never saw it, although Marlee Matlin is a relative on my mom’s side) is that it’s basically a load of hooey. [/QUOTE] Tell her I think she’s really hot (Marlee, not your Mom, though she may be too for all I know). ---
**Author:** ![CynicalGabe](https://avatars.discourse-cdn.com/v4/letter/c/3e96dc/32.png) [@CynicalGabe](https://boards.straightdope.com/u/CynicalGabe)\ **Post date:** [August 13, 2006, 4:57am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/15 "2006-08-13T04:57:00Z")
[QUOTE=Valgard] Everything I’ve read about the movie (never saw it, although Marlee Matlin is a relative on my mom’s side) is that it’s basically a load of hooey. [/QUOTE] So that means you can introduce me?? 😉 ---
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [August 14, 2006, 9:48am UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/16 "2006-08-14T09:48:31Z")
[QUOTE=Exapno Mapcase] No it doesn’t and no it doesn’t. The moon is not there if you don’t look at it nonsense has long been abandoned by physicists, including those who use CI. [/QUOTE] I was speaking metaphorically, as I thought you would recognize. C’mon, now. Address my points rather than my metaphors, please. There is a great deal you haven’t addressed. [QUOTE=Exapno Mapcase] I disagree. All the larger theories that marry QM and relativity will still have elements that are counterintuitive weirdnesses. [/QUOTE] So who’s arguing about marrying QM with relativity here? We’re talking about interpretations of QM and which are more intuitive; specifically, we’re arguing about your assertion that CI is the **most** intuitive interpretation. [QUOTE=Exapno Mapcase] For that matter, we can’t even agree on what is intuitive and what isn’t. [/QUOTE] If you’re saying that you and I can’t agree, that’s obvious. If you’re talking about interested people in general, you still have to try to establish that the view in which the outcomes of real, quantum events are determined arbitrarily by a mind’s whim is **more** intuitive than one in which consciousness plays no part, like every other facet of the universe. You still have to try to establish that the view in which even _asking_ whether Schroedinger’s Cat is alive or dead is absolutely forbidden is **more** intuitive than one in which at least the question itself isn’t meaningless. [QUOTE=Exapno Mapcase] I prefer to leave this to the philosophy majors. As long as all the interpretations are mathematically equivalent I agree with those who say that philosophizing about things we’ll never be able to touch and measure is an irrelevancy. [/QUOTE] Two points. (1): I guess you were then being disingenuous when you insisted that CI was **more** intuitive than the other interpretations since according to your last assertion they are all equal at least in that they are equally irrelevant, and (2): You must not have followed the link I provided above: [The shut up and calculate interpretation](http://www.mtnmath.com/faq/meas-qm-6.html), wherein it states: > [@](#): > > Advocates of this position like to argue that the existing framework allows us to solve all real problems and that is all that is important. Franson’s analysis of Aspect’s experiment1 shows **this is not entirely true**. Because there is no objective criterion in QM for determining when a measurement is complete (and hence irreversible) there is no objective criterion for measuring the delays in a test of Bell’s inequality. If the demise of Schrodinger’s cat may not be determined until someone looks in the box (see item 2) how are we to know when a measurement in tests of Bells inequality is irreversible and thus measure the critical timing in these experiments? (bolding mine) [QUOTE=Exapno Mapcase] And I believe that the universe is really there all the time, and does not depend on any definition of consciousness. But I don’t think that is incompatible with CI either. [/QUOTE] I strongly believe that last statement is incorrect. To the best of my understanding, it is fundamentally inherent in CI that quantum states are not merely unknown prior to measurement by a conscious entity, _they effectively have no state at all_. Even if they do, the outcome requires conscious measurement. It would follow that the Universe could not have begun and evolved without constant measurement of every single quantum “collapse” in all existence over all time. And, to me at least, that’s pretty damn counter-intuitive. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 14, 2006, 3:16pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/17 "2006-08-14T15:16:49Z")
[QUOTE=ambushed] Even if they do, the outcome requires conscious measurement. [/QUOTE] As I keep saying, no it doesn’t. You’re way behind the times. Many physicists have shown in many ways that macro events do not require conscious measurement. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [August 14, 2006, 4:05pm UTC](https://boards.straightdope.com/t/what-the-bleep-do-we-know/368356/18 "2006-08-14T16:05:20Z")
A few articles on decoherence from New Scientist: [Worlds Apart](http://www.newscientist.com/article/mg18224475.800.html) > [@](#): > > David Pritchard’s group at the Massachusetts Institute of Technology, for instance, has shown that if single atoms emit photons as they pass through a double slit in an interferometer, the photon’s wavelength determines whether the interference pattern will be washed out. “When the photon had a sufficiently short wavelength it ‘knew’ where it originated,” says Zurek. “That killed the interference.” And experiments at the École Normale Supérieure in Paris, France and at the National Institute of Standards and Technology in Boulder, Colorado, are making similar advances. > > So far, all the experimental results fit perfectly within the framework of quantum theory. But what actually causes the decoherence? In the Vienna experiments, for example, how does emitting photons destroy the wave-like properties of a molecule? > > One possible answer is that the photon is entangled - or informationally linked - with the molecule that emitted it, and also with whatever absorbs it, most likely the chamber’s inside wall. Establishing entanglement involves redistributing the information that the photon carries about where the molecule is, so that the fullerene molecule is no longer an isolated system. Through the absorption of its emitted photons its fundamental properties become linked to the rest of the world, and it starts to behave classically. [Cat-in-the-box](http://www.newscientist.com/article/mg17323334.400.html) > [@](#): > > But Penrose is quick to point out that he hasn’t just pulled his idea out of a hat. The Nobel laureate Richard Feynman once made a tentative suggestion that a theory uniting quantum mechanics and relativity might lead to an objective state reduction, and others have taken up and built on this idea. Penrose says he is simply continuing the work of this free-thinking minority. [Where does the weirdness go?](http://www.newscientist.com/article/mg15220525.200.html) > [@](#): > > The last section of the book is devoted to recent attempts to explain how ideas based on decoherence shed light on the measurement problem. Nobel prizewinner Murray Gell-Mann has explained decoherence as the entanglement of the interesting properties of a system with all the myriad other properties in which we have no interest. We are only interested in which horse wins a race, not what happens to the horseflies, collisions with air molecules and so on. Advocates of the decoherence mechanism claim that the summation over all these details for classical macroscopic objects causes all the strange quantum effects to disappear. [Bridge over the quantum universe: According to quantum theory, only an external observer can describe a physical system in terms of quantum mechanics. So how can we make sense of the quantum universe?](http://www.newscientist.com/article/mg13618424.500.html) > [@](#): > > This fact - that systems behave differently where they are coupled to a classical measuring device - can be understood in terms of a process called decoherence. When a classical measuring device is linked to a quantum mechanical object, the physical system that incorporates both of them has several independent parameters or degrees of freedom - that is, the total energy of the system can be distributed in several different ways. > > But we only ever use a small number of these degrees of freedom to describe the outcome of any measurement that we make. Ignoring large numbers of degrees of freedom leads to the phenomenon known as decoherence, which essentially suppresses the quantum interference between these different alternatives.