- #71
DrChinese
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ttn said:Vanesch, that is a brilliant example. :!)
Talk about both sides of the fence...
ttn said:Vanesch, that is a brilliant example. :!)
ZapperZ said:There is something highly unethical to talk about detection loopholes or detector efficiency while ignoring some very fundamental aspects and responses to such things.
Unlike most of you, *I* have been involved in actual measurement of such things since the start of my graduate school years, and since about 1 1/2 years ago, have been making high QE photocathodes. So I can talk about background noise, dark current, detector signal, blah blah blah till everyone turns blue. Trying to distinguish between what is "noise" and what is "signal" is a HUGE part of my work. If you look at the raw data from photoemission spectroscopy, for example (i.e. if you make cuts in the data in my avatar), you will see background noise, detector noise, dark currents, etc... Yet, according to SED (and Santos), the these "random" background noise can somehow mimic "actual signal"! NO KIDDING!
How convenient can that be when you can simply stick something in ad hoc, and voila, you can mimic the actual signal simply by burying something in the detector noise. Or did we forget that SED comes with its own set of assumptions about the nature of such background fluctuations? And unlike QM, many of these "assumptions" have not even been tested at the most fundamental level to even see if they are consistent with observation.
ZapperZ said:Photodetector performance is such a crucial issue, and has been studied so extensively, it is not even funny. Yet, I have seen no actual study done to see how well the detector performance actually matches any of SED's assumption. If we can verify everything from Fowler-Nordheim law at finite temperatures to and the Richardson-Dushman relations for photocathodes, how come this void for SED remains? One would think this is one very fundamental aspect of verification of SED to be taken seriously. Or maybe it is because it is not falsifiable?
However, the most disturbing and unethical aspect of this discussion is the complete void of citation to the TONS of issues that have already been addressed regarding the detection efficiency. All I see are references given to various detection issues that somehow supports SED's point of view on the Bell-type experiments (while ignoring the more stringent CHSH-type experiments). Nowhere was there any mention, by the so-call experts or students in SED, papers such as by S. Massar et al[1] or A. Cabello[2] that have either formulated a Bell-type inequality that are insensitive to detector inefficiency, or that one can distinguish already between quantum optics prediction versus classical with just a detector at 69% efficiency (which we already have!). Or what about Tittel et al.[3] experiment that analyzed their data without subtracting any accidental coincidences (something that many have claimed would reveal "non-quantum" results)?
Where are the rebuttals from the SED camp to those papers? Check any of Santos or Marshall's published papers and citations to their papers that addressed many of the issues that they brought up. So how come they did not address any of these? And I only did a very quick search on a few papers that I am aware of. The rest of you who, I presumed, work in this field or very much interested in it, should have a truckload of literature that you are sitting on. So why were these types of papers that have addressed such detector issues WITHHELD from being listed here alongside those that were so quickly advertized?
There are more of these type of papers. This is why I find such omission here very disturbing. It somehow conveys that the issues brought up by SED are "unanswerable" and thus, must be true. If you omitted such on info on purpose, then shame on you. If you simply were ignorant of all of these large bodies of information, then what else have you missed that you SHOULD have known before pushing this thing onto us?
Zz.
[1]S. Massar et al. PRA 66, 052112 (2002).
[2] A. Cabello PRA 72, 050101 (2005).
[3] W. Tittle et al. PRL 81, 3563 (1998).
DrChinese said:To Zz's point: Call it for what it is... SED is a speculative work-in-progress that has yet to yield a single useful discovery. In the meantime:
Experimental violation of a Bell's inequality with efficient detection
M. A. ROWE, D. KIELPINSKI, V. MEYER, C. A. SACKETT, W. M. ITANO, C. MONROE & D. J. WINELAND (Nature, 2001)
Abstract:
Local realism is the idea that objects have definite properties whether or not they are measured, and that measurements of these properties are not affected by events taking place sufficiently far away. Einstein, Podolsky and Rosen used these reasonable assumptions to conclude that quantum mechanics is incomplete. Starting in 1965, Bell and others constructed mathematical inequalities whereby experimental tests could distinguish between quantum mechanics and local realistic theories. Many experiments have since been done that are consistent with quantum mechanics and inconsistent with local realism. But these conclusions remain the subject of considerable interest and debate, and experiments are still being refined to overcome 'loopholes' that might allow a local realistic interpretation. Here we have measured correlations in the classical properties of massive entangled particles (9Be+ ions): these correlations violate a form of Bell's inequality. Our measured value of the appropriate Bell's 'signal' is 2.25 +/- 0.03, whereas a value of 2 is the maximum allowed by local realistic theories of nature. In contrast to previous measurements with massive particles, this violation of Bell's inequality was obtained by use of a complete set of measurements. Moreover, the high detection efficiency of our apparatus eliminates the so-called 'detection' loophole.
To Vanesch's analogy (with thermodynamics): We are being asked to accept that "noise" accounts for violation of Bell Inequalities. Yet regardless of detector efficiency, the results are the same! Aspect's early inefficient tests yield almost precisely the same results as the later, more refined tests (as compared to the predictions of QM). Where is the movement towards the SED predicted values you might expect when visibility increases?
And to anyone who is actually in SED's court: If Malus' Law does not hold, please answer the following question: What are the values for the coincidence rate at 0, 22.5 and 45 degress (as compared to the cos^2 function from both classical optics and QM)? A specific value, so we have something to discuss... after all, it can't match QM without running afoul of Bell...
Maaneli said:1. Moreover, the paper you cited does not apply to SO, as I had already mentioned that the theory has not yet been applied to electrons, let alone ions.
2. But even then, you should probably know that that paper you cite is also no longer considered a valid test of local realism because the two subsystems (the two ions) were not really separated systems during measurement and so the test cannot be considered a real implementation of a detection loophole-free test of Bell inequalities, even if it represents a relevant progress in this sense. Ands this is a conclusion confirmed in personal correspondences with Kwiat and Genovese.
Careful said:1. I thought that one did not close the locality loophole (the two detectors were too close to each other).
2. Perhaps Zapperz can provide an explanation for us for say an electron detector (I promise not to turn blue) ?!
Careful
Maaneli said:Zapper, the stochastic noise isn't really ad-hoc in SED.
"What is entanglement?" Emilio Santos.
I conjecture that only those states of light whose Wigner function is positive are real states, and give arguments suggesting that this is not a serious restriction.
But even if you still considered this inadequate, you cannot dismiss the physical consequences of classical fields + stochastic noise. Like Vanesch is emphasizing, it is certainly not just a coincidence that these fundamental tenets of SED explain all the physical phenomena which were the justification for abandoning classical electrodynamics and optics and accepting QM and quantum optics.
As has already been mentioned, in SED there are some preliminary ideas for theories of detection and how detectors work. I also already cited these papers by Santos. But keep in mind that though SED has not completely addressed detection theory, it must be qualified that it was only until 2002 that the stochastic optics formalism was completed to account for all the optical tests of Bell's theorem. Moreover, Marshall has since retired from the field due to his health, thus making Santos essentially the only one actively working in the field. And both men are in their early 70's. So progress along the lines of formulating a theory of detection will understandably be very slow, until there is young blood in this field.
Regarding those detection efficiency papers you mentioned, while I was unaware of the papers you cited, the test requiring the 69% efficiency is not relevant to stochastic optics. To refute SO requires detection efficiencies >87%. Moreover, that paper does not reference stochastic optics at all. I don't know the details of Tittel's paper.Massar's proposal may have been misunderstood by you. I just did an arxiv search under his name and found an even more recent paper than the one you cite, in which he says the following:
Violation of local realism vs detection efficiency (2003) Serge Massar, Stefano Pironio
"We put bounds on the minimum detection efficiency necessary to violate local realism in Bell experiments. These bounds depends of simple parameters like the number of measurement settings or the dimensionality of the entangled quantum state. We derive them by constructing explicit local-hidden variable models which reproduce the quantum correlations for sufficiently small detectors efficiency."
http://lanl.arxiv.org/abs/quant-ph/0210103
So, these resistances to detector efficiencies put bounds on the validity of the LHV's that Massar et al. constructed. They do not make any reference to any of Santos or Marshall's work.
It's important to understand that papers in this field of semiclassical approaches to optics and QM are fairly scattered. It is very difficult to be an expert in the work of Santos and Marshall, whose publications span 15 years, and to also be aware of every possible spin-off or criticism of their work since then. So no one - at least not me - is withholding information. Not being aware of every single publication ever in this field, or not being able to answer every single criticism posed, does not at all imply that SED can't answer these questions. It just hasn't been given the time or man power to address them.
DrChinese said:1. Glad to know that only photons are local realistic.
2. This is a valid experiment which closes the detection loophole. They do not claim that strict einsteinian locality is maintained. If you already believe in local reality, then requiring spacelike separation isn't relevant to the detection issue. (Think about it...)
ZapperZ said:How could you not say these are not ad hoc, and then quote what is clearly a "shove-in-by-hand" conjecture?
ZapperZ said:But you're willing to somehow consider it is purely a coincidence that ALL of the Bell-type, CHSH-type, and GHZ-type experiments are violated.
ZapperZ said:Then people who are trumpting its horns are putting the care WAY before the horse, like maybe in the next county. SED has a serious shortcoming of verifying the most fundamental aspect of what it is predicting at the detector level. Those of us who depend on a detector detecting VALID signals are amazed that one could get something that is nothing more than background noise to mimick a real signal. If you truly think that is true, then stop using your modern electronics, because the band structures of many semiconductors that we verified using photoemission obviously are WRONG.
This is why I asked for SED to spew out an agreement to ARPES, etc. If you cannot produce something that is the CLOSEST to the fundamental level of your theory, how do you know that all those you build on top of are valid?
ZapperZ said:Look at the paper *I* cited. They cited Santos's work. I also want to let you know that I would rather be given the published version of a paper, and not the arxiv reference - unless of course you don't want me to do a citation index search on these things.
ZapperZ said:I strongly disagree. I came from the high-Tc superconductivity field in which the number of papers being published PER WEEK exceeds many fields in a year! And I don't want to put this field down, but I bet you the frequency of papers published in this field is miniscule when compared with condensed matter. So your excuse of not knowing the existence of such-and-such a paper rings hollow in my book, especially earlier when you pleaded ignorance of GHZ experiments. All I did today was do a quick citation index on one of Santos's papers and out comes several other citations. If someone who isn't an "expert" in this field and have only followed it closely as an interested party can obtain such references, how difficult can this be?
Zz
Maaneli said:To the second point, you can't be serious . If the ions are not separate systems, then it is even easier to suggest local causal influences between the ions...
DrChinese said:Now you are being funny.
QM needs nothing else to fill in the blanks, and neither would an explicit non-local theory such as Bohmian Mechanics (nor MWI for that matter). A local realistic theory would! There would need to be a previously unknown force or causal agent. And that, my friend, should be detectable using conventional means. And they would CERTAINLY need to be explicitly present in SED to explain this experiment.
So throw out the experimental results that bother you, and sleep tight tonight.
Maaneli said:I don't understand this sentence. I am willing to consider the possibility that all of these experiments are consistent with local hidden variables that also violate the inequalities. In fact these inequalities describe a specific class of LHV's which are violated. And there are different classes of LHV's, such as stochastic optics, that also violate those inequalities. So if LHV's are fundamental, and QM is an accurate approximation of these inequality violating LHV's, then it is pefectly reasonable why these experiments violate the said inequalities. I don't see how that makes me consider these experiments to be a coincidence.
Maaneli said:I don't understand this sentence. I am willing to consider the possibility that all of these experiments are consistent with local hidden variables that also violate the inequalities. In fact these inequalities describe a specific class of LHV's which are violated.
SED and SO theorists know that what they build on top is valid simply because it works, meaning that to the extent that SED and SO have been analyzed and applied, they have been as successful as QM in making predictions consistent with current experiments. And it is these approaches which the SED theorists build upon. Now by no means does that guarantee that the current approach of SED will continue to be successful. In fact, I am willing to bet that for SED to develop an accurate theory of detection and atomic band structure, it will have to be modified in some way, or some ingenious new approach to problem the will have to be developed. Now I could give you my thoughts on precisely how one could do this, but I suspect that would only be suitable for the independent research forum. Nevertheless, I think SED and SO's current success are good enough to build upon.
That's true that your field has more publications per week than any other field. However, I would guess that even then you don't have the time to read every paper and even for those you do read, my guess is that you are not an expert on them.
Or, at least it takes some time to become an expert. Also, you are a professional working CM physicist who's job it is to read these papers. And you seem to have been doing this for at least 20 years. I on the other hand am still a full-time physics student and have only seriously entered this field of theoretical and experimental quantum and stochastic optics in the past year. And I don't want to have a trivial knowledge of every publication in the field.
ZapperZ said:You have no ability to say that (no SED proponent can) when you haven't shown how CHSH and GHZ experiments agree with SED. Even Santos haven't made that claim!
ZapperZ said:Look at what is happening to QM. Even with all its successes, we STILL tests its fundamental building blocks, such as the superposition principle. This is what the Stony Brook/Delft experiements were designed to test. I've been asking SED proponents for YEARS to show me ONE complete simulation of a typical photoemission spectroscopy result. Just ONE. This will truly test of the fundamental assumptions of SED in regards to how photons interact with a material to produce an electrical signal, AND, that signal can, in turn, tells us something about the material itself!
This is such at the most fundamental and basic level that I don't understand why SED people don't just jump into it. Success in it means that you have a whole bunch of condensed matter physicists paying a closer attention to what you have to say!
ZapperZ said:At the very least, I'm AWARE of them, and if the same subject came up, I would have remembered reading something about it. I certainly would not have withheld information on it even it was contrary to what I was going to present.
ZapperZ said:I find that rather incredulous. I mean, GHZ papers are "trivial knowledge"? I pay attention to everything that Zeilinger publishes, and I'm not even in the SAME field! I mean, this guy could get the Nobel Prize some time in my lifetime. I would hardly think that such a paper, appearing in PRL and Nature no less, would be considered as "trivial knowledge".
Zz.
RandallB said:Gordon
(Or as you call yourself: MW, Mostly Wrong, QuantunEnigma, any more?)
Oh please, you think your a “Rich Thinker”
In post #66 you ask DrC for a negative probability example when he has already given you just that in his link that you quoted back to him!
On Aug 20 your site had only one working page with links to dozens of THIS PAGE DOWN BEING WORKED on links. That hardly counts as “many pages”,
On Aug 21 you put up about a dozen more pages, but any chance you might document your claim the “Bell Logic is false” in your explanations of your versions of W ‘locality’ and ‘factoring’ is still buried behind “This Page Down” links.
Then on the 22nd rather than use your MW id you created the extra QuantunEnigma id to lure DrC and others to your site.
That’s not rich thinking – that’s baiting and dishonest.
You owe both DrC and Zz an apology.
Careful said:So all I am asking here is how one can be sure that if one detects a signal, it corresponds to only one electron scattering off the apparatus ? Or, when no detection is made, no electron is passing ?
If you can show me where you admitted to making a mistake in intentionally playing tag team with MW on this thread to promote his website (“I didn’t know” is a 5 yr olds excuse not an admission of error or apology) then I acknowledge that as an apology, but I don’t find anything like that in your posts.QuantunEnigma said:I told you it was a mistake.
Where did you see a claim that experiment produces negative probability counts (frequencies?) that is a calculation from using the Bell Theorem.an experiment that proves negative probabilities ……… Did they come out with negative relative frequencies? ……. you know the secret address where DrC example is
stop hiding behind the gurus and think for yourself unless you think that science is like religion and facts do not matter any more?
RandallB said:If you can show me where you admitted to making a mistake in intentionally playing tag team with MW on this thread to promote his website (“I didn’t know” is a 5 yr olds excuse not an admission of error or apology) then I acknowledge that as an apology, but I don’t find anything like that in your posts.
Where did you see a claim that experiment produces negative probability counts (frequencies?) that is a calculation from using the Bell Theorem.
And what secret address? - you quoted it in your post #66;
follow his reference links if you don’t like DrC’s short version.
What gurus, is that what you consider to MW to be? I’ve shared with the people that count on here where my position disagrees with theirs but I don’t demand anyone accept or listen to my ideas until I have find a real way to support them.
Fact is it is you and MW that demand to be listen to, just for claiming Bell Logic is Wrong or ‘Silly”.
MW claims to have documented it for years but has been unable to cut and paste a single relevant word or fact supporting such a huge claim (religion?) anywhere I can find.
Gordon was asked to “show the beef” on this two years ago – tell him to put it on his website not here – if it is more than a little Chicken or Turkey on the bun, maybe I’ll find it. The two of you have done more than enough to destroy your own credibility to justify posting here.
Yet you claim a success in post #66 in hooking one person to take the time to vainly search for a straight answer on MW’s web site;
and then insult me and my “poor mind”, for doing so.
So this is my last response to you as if you keep this up you are Zz’s problem anyway – he does a needed and good job at keeping this overall forum rational and is more than fair. (By the way, Thanks Zz for what you do for the group that goes unseen)
QuantunEnigma said:because I do not know how to make it a hidden legal link to show what we are talking about.
ZapperZ said:Re-read the Guidelines that you have agreed to. Personal, unverified theories and ideas are NOT allowed. If you have a personal theory to push, do so in the IR forum. You have been told this before, and I very seldom repeat what has been said.
Furthermore, citation to some website does NOT strengthen your case! So stop doing that. This is not how science, and especially physics, is done. If you think you have a valid idea, cite a respected peer-reviewed journal.
I expect that this is the last time I have to explain this.
Zz.
QuantunEnigma said:QUOTE OF ZZ ACTION
The secret site is the one that you and i are monitoring, that is all. The one that cannot be mentioned like this [SPAM link removed - the NEXT time I have to do this, you're gone! - Zz.] because I do not know how to make it a hidden legal link to show what we are talking about. If you would show me how please I would edit this posting and leave in peace. END
Sir, I am writing to ask please correct the words of your deletion. Unless I am mistaken. The site IS NOT A SPAM SITE because not like Physics Forums it has no advertisements and I can see no reward for clicks or views. "It is a free public service science blog with references to 100 peer reviewed articles and it is based on peer reviewed and published theory that has not been changed or refuted or modified."
You are the one who can delete but in fairness your deletion should not distort facts unless i do not understand what is a SPAM SITE please. Can you say? Site deleted or personal science blog deleted.
Also, because the site is edited every day I think it cannot work under a loss of editorial freedom which your referral appears to require. The author thinks that.
I am note arguing with you right to delete, only that be fair like a scientist and present facts please. Unless i am wrong
Careful said:1. Could I ask you why you believe the dark current (or dark count) to be the only parameter which has something to do with detector efficiency ? Dark current is just the internal thermal current of electrons in the apparatus under assumption of absence of external fields. This is what you substract from the received signal, but that does not imply automatically that the received signal is what you get from the source. I guess the dark current could interfere with the received signal so that some distortion of the latter occurs (although it could very well average out in which case dark current would be irrelevant - could someone comment on this ?), but that does not fix your efficiency. Moreover it is not so clear what this has to do with the zero point field in SED (the latter would only produce quantum corrections to the dark current I presume), there the zero point field is non thermal and has no observable effects (it is believed to provide atomic stability of course) unless one has different boundary conditions for the electromagnetic field or some particle is accelerated through it (like in the Unruh effect). This is for example how they can explain the Casimir Polder effect and how a zero point field can influence the dynamics of interacting fields (detection process).
2. Moreover, if you use presumed sources of ``entangled photons'' as a way to calibrate your detectors, it becomes rather impossible (from a logical point of view) to consider the possibility that entanglement might not exist in the first place, no ? :-)
Careful
Careful said:Now, you seem to be confused by my position. I am a local realist and I could really offer you good reasons why a non local world view is nonsensical (actually it is pretty easy to give a crazy local (in the strict sense!) theory behind the Von Neumann measurement postulate if you are creative enough) but I prefer to keep an open mind. As far as I am aware, it is possible to give a local theory of EPR with a local measurement dynamics (and without denying reality) - see my allusion to negative probabilities (you might be interested to read about this).
DrChinese said:I am interested in negative probabilities because I think any local realistic model will yield probabilities greater than 1 or less than zero somewhere along the line. The reason I "know" this is because of Bell's discovery.
ttn said:Could you give an example of a theory which is "local" but not "realistic" and which agrees with the QM predictions here? Or more basically, do you think that such a theory is (in light of Bell's discovery) possible?
If not, why use the cumbersome and vague phrase "local realism" when, evidently, you just mean "local"?
DrChinese Sure said:Dear David, a rebuttal of your ''negative probability case" (from your website) may be found at [link deleted]
I would welcome any comments, especially any which make your case clearer to the general reader. Of course, if I've mispresented it, please let me know that too.
wm
Careful said:** I am a local realist and I could really offer you good reasons why a non local world view is nonsensical (actually it is pretty easy to give a crazy local (in the strict sense!) theory behind the Von Neumann measurement postulate if you are creative enough) but I prefer to keep an open mind. As far as I am aware, it is possible to give a local theory of EPR with a local measurement dynamics (and without denying reality) - see my allusion to negative probabilities (you might be interested to read about this). However, on the other side, it is still possible to claim that a ``less quantal'' point of view is possible, see SED or better Barut self field. So, one would better do the experiment with neutral Kaons, or do experiments in which local realist predictions (deviating from the QM ones) can be checked. This would settle the matter more easily. But in ANY case (there is in the worst case a lack of creativity), there is no obvious problem with local realism as far as I am concerned, only some types of ``naive'' local hidden variable theories (the ones assuming screening off *and* dichotomic outcomes) could be killed off, but where remains the conclusive series of experiments ?
Careful
wm said:Dear David, a rebuttal of your ''negative probability case" (from your website) may be found at [link deleted]
I would welcome any comments, especially any which make your case clearer to the general reader. Of course, if I've mispresented it, please let me know that too.
wm