# Quantum physics and "observers".... **URL:** \ **Category:** Factual Questions\ **Created:** [September 17, 2003, 5:29pm UTC](https://boards.straightdope.com/t/quantum-physics-and-observers/202175 "2003-09-17T17:29:58Z")\ **Posts on this page:** 3\ **Page:** 2
**Author:** ![ambushed](https://avatars.discourse-cdn.com/v4/letter/a/3bc359/32.png) [@ambushed](https://boards.straightdope.com/u/ambushed)\ **Post date:** [September 21, 2003, 2:55am UTC](https://boards.straightdope.com/t/quantum-physics-and-observers/202175/21 "2003-09-21T02:55:18Z")
> [@](#): > > \*Originally posted by MC Master of Ceremonies \* > **ambushed, the conceptual problems of quantum mechanics is part of any quantum mechanics course.** So what? If you still believe that CI is the predominant view among QM experts, **your education is lacking in that regard!** You’re relying on obsolete or otherwise incorrect information. > [@](#): > > \*Originally posted by MC Master of Ceremonies \* > **Feynman’s time reversibilty [sic] is used in more advanced QM and Feynman diagrams are of real pratical [sic] use, though Feynman himself didn’t argue for it as a QM interpretation.** That’s debatable. To the extent he didn’t favor time reversibility, he favored “Many Worlds”, not the hopelessly obsolete CI! Furthermore, Time Reversibility **IS** being vigorously and successfully defended by Feynman’s heirs such as Victor Stenger, et al. > [@](#): > > \*Originally posted by MC Master of Ceremonies \* > **The transactional interpretation takes Feynman’s time reversibilty [sic] a littel [sic] further, though IIRC due to the problems with absorbers it may violate casuality [sic].** Many interpretations find that apparent causality violations are far less odious philosophically than the wretched ugliness of CI. **ALL** interpretations have had to trade off one difficultly for another, so that’s nothing new. But the fact is that the obsolete Copenhagen Interpretation has the worst problems of all! > [@](#): > > \*Originally posted by MC Master of Ceremonies \* > **As I said before there are a few problems with Many worlds theory, firstly there are the ontological problems … [blah, blah, blah]** You really need to read more carefully. I already indicated that I do not personally endorse MWI! However, there is absolutely no doubt that it is the predominant view held by experts in quantum physics, including Nobel Prize winners. > [@](#): > > \*Originally posted by MC Master of Ceremonies \* > **I mentioned De Briglie[sic]-Bohm ‘matter waves’ above this is generaly [sic] rejected for several reasons… [blah, blah, blah]** Irrelevant. There is absolutely no doubt that MWI is the predominant view held by experts in quantum physics, including Nobel Prize winners, and that no experts in the polling we’ve referred to previously stand by Copenhagen, which is hopelessly obsolete because of its embarrassing wealth of fatal philosophical flaws. > [@](#): > > \*Originally posted by MC Master of Ceremonies \* > \*\*The idea that the Copenhagen Interpretation is not very much alive and kicking is laughable as it is the convential [sic] interpretation. \*\* Conventional wisdom is usually wrong. It is your youthful and under-educated worship of the CI which is laughable. Talk to us again in 10 years, and if by then you’ve become a creditable physicist, you’ll have abandoned CI just like all of your peers. ---
**Author:** ![moriah](https://avatars.discourse-cdn.com/v4/letter/m/b2d939/32.png) [@moriah](https://boards.straightdope.com/u/moriah)\ **Post date:** [September 22, 2003, 3:05pm UTC](https://boards.straightdope.com/t/quantum-physics-and-observers/202175/22 "2003-09-22T15:05:23Z")
Dear OP, The snarky quantum-philosophical debate you incited (you should be ashamed of yourself!) is a result of the fact that your questions have no definitive answers at this point. Consider the ‘fact’ that quantum ‘things’ sometimes behave like particles and sometimes behave like waves. This leaves us saying, “Are they really waves or particles, or are they both?” But most likely the answer is that they are neither. It’s just that in one particular instance, they can be mathematically modeled as particles, and in another instance, as waves. These observation really don’t help us to pin down what they exactly are. And so, it is even more tricky to try to pin down and explain what happens in the moment that they phase from waves to particles. The fact is that observation shows that they do phase from waves to particles when we observe them. We really don’t know what exactly causes the wave to ‘collapse’ (if it is truly collapsing at all) or what exactly the wave is doing before the collapse. And this brings up a third problem in the philosophy of reality of quantum mechanics (the first is the seeming wave-particle duality; the second is how and why a wave collapses to a particle): that is, how do quantum ‘things’ wind up acting like classical macroscopic objects when they react with and are incorporated into macroscopic objects? ## Shrodinger’s paradox was formed to point this out (can one force a macroscopic entity, like a cat, to conform to the probability laws of quantum mechanics?). It seems that when observed, or when combined in the aggregate, quantum ‘things’ no longer follow quantum laws, but become classical physical objects. Some physicists have proposed that there is a resonance field at work that causes all those probabilistic effects to cancel each other out (or amplify into a single state). We just don’t know for sure yet, all we have are theories to argue over. Peace. The tau-shimmer particle is **both** a floor wax particle **and** a dessert topping particle. ---
**Author:** ![MC\_Master\_of\_Ceremonies](https://avatars.discourse-cdn.com/v4/letter/m/bb73d2/32.png) [@MC\_Master\_of\_Ceremonies](https://boards.straightdope.com/u/MC_Master_of_Ceremonies)\ **Post date:** [September 23, 2003, 8:41pm UTC](https://boards.straightdope.com/t/quantum-physics-and-observers/202175/23 "2003-09-23T20:41:29Z")
> [@](#): > > \*Originally posted by ambushed \* > \*\*So what? If you still believe that CI is the predominant view among QM experts, **your education is lacking in that regard!** You’re relying on obsolete or otherwise incorrect information. No I’mrelying on the fact that I know people in the field and my textbook published by the IoP only two years ago. > [@](#): > > That’s debatable. To the extent he didn’t favor time reversibility, he favored “Many Worlds”, not the hopelessly obsolete CI! Furthermore, Time Reversibility **IS** being vigorously and successfully defended by Feynman’s heirs such as Victor Stenger, et al. I’m not attacking, but it’s more of a side interpretation > [@](#): > > Many interpretations find that apparent causality violations are far less odious philosophically than the wretched ugliness of CI. **ALL** interpretations have had to trade off one difficultly for another, so that’s nothing new. But the fact is that the obsolete Copenhagen Interpretation has the worst problems of all! But that’s exactly the kind of thing that a non-scientist would say as a theory with non-locally acting fileds like Bohmian mechanics is incompatible with relativity, so this theory is no good for the more advanced applications of relativistic quantum mechanics. > [@](#): > > You really need to read more carefully. I already indicated that I do not personally endorse MWI! However, there is absolutely no doubt that it is the predominant view held by experts in quantum physics, including Nobel Prize winners. > > Irrelevant. There is absolutely no doubt that MWI is the predominant view held by experts in quantum physics, including Nobel Prize winners, and that no experts in the polling we’ve referred to previously stand by Copenhagen, which is hopelessly obsolete because of its embarrassing wealth of fatal philosophical flaws. The thing is that you don’t know the maths which is what the Copenhagen interpretation describes on a more abstract level and your views are personal opinion rather than informed comment. > [@](#): > > Conventional wisdom is usually wrong. It is your youthful and under-educated worship of the CI which is laughable. Talk to us again in 10 years, and if by then you’ve become a creditable physicist, you’ll have abandoned CI just like all of your peers. \*\* Again as I said before I’ve not indicated my own preference, indeed until recently I was very much MWI but after reading David Deutsch’s book (which was actually pro-MWI) I became more aware of the huge ontological problems it faces (for example David Deutsch had to set aside a large part of his bookjust to argue that MWI WAS even a theory). [Previous page](https://boards.straightdope.com/t/quantum-physics-and-observers/202175.md?page=1)