tag:blogger.com,1999:blog-22973357.post114834585270765642..comments2023-09-27T07:44:19.769-04:00Comments on Sabine Hossenfelder: Backreaction: NonlocalitySabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comBlogger31125tag:blogger.com,1999:blog-22973357.post-1151516464190574102006-06-28T13:41:00.000-04:002006-06-28T13:41:00.000-04:00IIRC, A and B need to worry about more than each o...IIRC, A and B need to worry about more than each other's "particle-oriented" wavefunctions, they also need to avoid collapsing those into the "environmental" wavefunctions of their surroundings. I'm pretty sure that interactions with the dog would be enough to do that. <BR/><BR/>And consistency would be enforced via the static plenum -- that is, once "either end" of the wavefunction collapses,Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149825620550231682006-06-09T00:00:00.000-04:002006-06-09T00:00:00.000-04:00There is another interesting aspect that can be fu...There is another interesting aspect that can be further introduced, I made some comments re:<BR/>http://arxiv.org/abs/gr-qc/0403001<BR/><BR/>on the PF forum before I got banned(again!)..but I have extended the implications original post by Sabine, but will leave the link for now, and will hopefully place a simplistic overview of another thought experiment.<BR/><BR/>P.S PF poster Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149101907496305842006-05-31T14:58:00.000-04:002006-05-31T14:58:00.000-04:00The Emergent Probabilities paper is pretty good, b...The Emergent Probabilities paper is pretty good, but noticably avoids the issue of non-commuting operators and the Hiesenberg Uncertainty relationships. I may be reading the paper wrong, but their logic would seem to allow for unlimited precision in measuring non-commuting operators simultaneously. There is more to quantum mechanics than merely probabilities.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149069590856902002006-05-31T05:59:00.000-04:002006-05-31T05:59:00.000-04:00paul valletta said... Take a single particle, with...<I>paul valletta said... <BR/><BR/>Take a single particle, within a SINGLE location,(box) [...]<BR/><BR/>you cannot create TWO detectors[...]<BR/><BR/>one observer can observe two particles in ONE box,Two observers can observe one particle in one box. <BR/><BR/>Two observers 'cannot' observe One particle, at two non-local reference frames in a single instant? </I><BR/><BR/>Hi paul, <BR/><BR/>the Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149062424549209142006-05-31T04:00:00.000-04:002006-05-31T04:00:00.000-04:00insightaction said...What is measurement anyways? ...<I>insightaction said...<BR/><BR/>What is measurement anyways? I strongly suspect that if I were to contemplate those sorts of questions I'd be bettter of teaching Yoga for a living.</I><BR/><BR/>Why? I find the question of how the measurement happens really important. I admit though that I can't relate to all the metaphysical crap that some people like to attach to the question. I think there Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149045798440522492006-05-30T23:23:00.000-04:002006-05-30T23:23:00.000-04:00Hi, again.Take a single particle, within a SINGLE ...Hi, again.<BR/><BR/>Take a single particle, within a SINGLE location,(box) seperate the particle, send the TWO half's to locations "outside" the initial box?<BR/><BR/>Neat trick I know, BUT you cannot create TWO detectors,(initial box containing two particles is observed by a single detector) unless one create's two "boxes" from the original One?<BR/><BR/>It surely makes no difference to Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1149007425953292952006-05-30T12:43:00.000-04:002006-05-30T12:43:00.000-04:00Think big-exactly! But then I would have to tampe...Think big-exactly! But then I would have to tamper with the most unfortunate of questions: What is measurement anyways? I strongly suspect that if I were to contemplate those sorts of questions I'd be bettter of teaching Yoga for a living.<BR/><BR/>I was thinking of interference patterns mostly, and the idea of storing and transporting entangled states. Could an etched quantum dot store a p_t Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148926052235257072006-05-29T14:07:00.000-04:002006-05-29T14:07:00.000-04:00InsightAction said... We are still side stepping t...<I>InsightAction said... <BR/>We are still side stepping the issue of how the observers are comparing the angles between the detectors</I><BR/><BR/>Indeed we are. Think big: quantum mechanics is not merely measuring spins. What do you do with other experiments when up-down-left-right is not sufficient? Is the 'long ramble' enlightening for measuring interference patterns or P_T distributions? Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148925707296855832006-05-29T14:01:00.000-04:002006-05-29T14:01:00.000-04:00paul valletta said... The problem lay in the fact ...<I>paul valletta said... <BR/><BR/>The problem lay in the fact A and B cannot be in a single space at the same instant. Being at two seperate locations, determines that observers cannot collapse "other" observer's frame of reference. </I><BR/><BR/>Hi paul,<BR/><BR/>I don't think that is where the problem comes from (if there is any). You are right that in the relational approach two observers at Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148861909023109812006-05-28T20:18:00.000-04:002006-05-28T20:18:00.000-04:00The problem lay in the fact A and B cannot be in a...The problem lay in the fact A and B cannot be in a single space at the same instant. Being at two seperate locations, determines that observers cannot collapse "other" observer's frame of reference.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148667899420541102006-05-26T14:24:00.000-04:002006-05-26T14:24:00.000-04:00We are still side stepping the issue of how the ob...We are still side stepping the issue of how the observers are comparing the angles between the detectors.<BR/><BR/>Something very tricky is occuring there.<BR/><BR/>After all it is completely reasonable to compare the output from the detectors, and that comparison will yield any correlation between -1 and +1. The spooky part is that this number relates so nicely to the angle between the Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148633854694061622006-05-26T04:57:00.000-04:002006-05-26T04:57:00.000-04:00Who said: Hey, this is your blog which first and f...<I>Who said: Hey, this is your blog which first and foremost should be fun and about your ideas friends etc. [...] Wont pursue it here.</I><BR/><BR/>Hi Who, Thanks for your comments. Don't worry, I have fun with my blog :-) Reading your last post I think we do agree anyway. There is nothing spooky in the sense as there is never information transmitted non-locally. Also, the observers never Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148527037378839442006-05-24T23:17:00.000-04:002006-05-24T23:17:00.000-04:00Hi Bee, our posts crossed. I was interupted at com...Hi Bee, our posts crossed. I was interupted at computer and sent my 4:30 while unaware of your 4:10 (times approximate).<BR/><BR/>I THINK I SEE YOUR POINT. It is here:<BR/><BR/>**They need to compare their local results. If you assume that both ALWAYS agree, then you have to explain that. This is the spooky non-locality.**<BR/><BR/>To me it is not spooky and it is something they discover AFTER Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148513534362950822006-05-24T19:32:00.000-04:002006-05-24T19:32:00.000-04:00What actually happened is that when it came time ...What actually happened is that when it came time to do the experiment, B could not remember whether he was supposed to point the machine East or West. As a compromise, he points the machine North and measures the spin. He gets +1, so he shoots the dog.<BR/><BR/>After a while A, who is the principal investigator comes to check up on the results. When A hears what has happened he is completely Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148512213726395162006-05-24T19:10:00.000-04:002006-05-24T19:10:00.000-04:00Who said: I think the point is simply that there i...<I>Who said: I think the point is simply that there is no non-local collapse of anybody's wavefuntion!<BR/><BR/>A's wavefunction about the OTHER electron does not collapse until he actually hops a jet and GOES to where B is.</I><BR/><BR/>Hi Who, thanks for your comment. I get the point. It doesn't take a non-local collapse. The wave-function does not collapse non-locally. But a measurement of oneSabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148499497253995272006-05-24T15:38:00.000-04:002006-05-24T15:38:00.000-04:00** Now the new thing is, let A measure +1, and B m...** Now the new thing is, let A measure +1, and B measure +1. **<BR/><BR/>unrealistic assumption, I think, Sabine. so that your critique from that point on does not apply<BR/><BR/>you asked for help understanding the paper which I will try to give, as well as I can (pretending to no special understanding myself!).<BR/><BR/>I think the point is simply that there is no non-local collapse of Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148472357532895712006-05-24T08:05:00.000-04:002006-05-24T08:05:00.000-04:00Hahaha, I'd rather think that nonlocality is more ...Hahaha, I'd rather think that nonlocality is more brain twisting! Relationalism is a pragmatic philosophy that ensures that only the most obvious rational elements of a theory, ones that we can justify, are used to formulate the theory itself---what can be less brain twisting than that?! We can justify that observer's only have partial information but we cannot justify that there exist Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148458548468459692006-05-24T04:15:00.000-04:002006-05-24T04:15:00.000-04:00Hi BeeThanks for pointing me to the article!I kind...Hi Bee<BR/><BR/>Thanks for pointing me to the article!<BR/><BR/>I kind of expect that RQM will not give different predictions than other interpretations of QM, that it is "merely" a way to interpret the predictions. So you could say that it's a matter of personal taste...<BR/><BR/>In that case, I opt for non-locality over everyone his own reality.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148422629892674372006-05-23T18:17:00.000-04:002006-05-23T18:17:00.000-04:00I don't think the relational interpretation implie...I don't think the relational interpretation implies solipsism. It is only if A and B is in absolute causal isolation, that they can disagree about a measurement. Like if A is behind a black hole horizon. In most other cases, information about the measurement will have reached from A to B via decoherence processes.<BR/>That's what I think anyway.<BR/><BR/>I also think you have a nice blog.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148419233508635382006-05-23T17:20:00.000-04:002006-05-23T17:20:00.000-04:00Maybe this is just a philosophical comprise but I ...Maybe this is just a philosophical comprise but I have come to think of spin entanglement experiments as not so much measureing spin of particles but rather measuring the average angle between detectors.<BR/><BR/>The correlations are not a function of cause and effect, after all who detects first is relative to the observer, but rather a result indicating that the anlge between the detectors is aAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148415229996432532006-05-23T16:13:00.000-04:002006-05-23T16:13:00.000-04:00Hi Tom, welcome. Thanks for the nice words :-)anon...Hi Tom, welcome. Thanks for the nice words :-)<BR/><BR/><I>anonymous said: But I see nothing wrong with a relational definition of elements of reality (isn't this almost what Einstein suggested with his spacetime coincidences...).</I><BR/><BR/>Well, I didn't say there is something wrong. Just that I am not sure what the gain is of such a re-interpretation to get rid of the non-local collapse. It Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148414936429416272006-05-23T16:08:00.000-04:002006-05-23T16:08:00.000-04:00insightaction said: The correlations of the EPR pa...<I>insightaction said: <BR/><BR/>The correlations of the EPR paradox depenend on being able to reliably compare the arrival times of particles and the angles between the polarized filters.<BR/><BR/>[...]<BR/><BR/>Would all observers be able to agree on arrival times and angles between polarizers if the system was accelerating? <BR/></I><BR/><BR/>hmmm, if the system was accelerating they wouldn't Sabine Hossenfelderhttps://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148412135108408052006-05-23T15:22:00.000-04:002006-05-23T15:22:00.000-04:00Hiyah,My first post: Greetings. I really like you...Hiyah,<BR/><BR/>My first post: Greetings. I really like your blog (I came to it from al's reality conditions), he's a friend at nottingham. I too am very interested in Rovelli and Smerlak's approach, although I am relatively happy with it. The only thing I don't really like is thier definition of observer because I take a different view as expressed in quant-ph/0604201. But I see nothing Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148409271837824662006-05-23T14:34:00.000-04:002006-05-23T14:34:00.000-04:00The correlations of the EPR paradox depenend on be...The correlations of the EPR paradox depenend on being able to reliably compare the arrival times of particles and the angles between the polarized filters.<BR/><BR/>EPR experiments cxarefully control just that uncertainty.<BR/><BR/>Now if the detectors and polarizers were accelerated or even moving close to the speed of light I don't see why the correlations should be maintained.<BR/><BR/>Would Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-22973357.post-1148408144879872232006-05-23T14:15:00.000-04:002006-05-23T14:15:00.000-04:00Hey Bee.I concur fully with your comment on relati...Hey Bee.<BR/><BR/>I concur fully with your comment on relational EPR, and that it seems to imply this sort of ultra soliplism.<BR/><BR/>I think Rovelli disagrees on this point, or at least this is not the scenario he wishes to describe/create.Anonymousnoreply@blogger.com