[2020-06-26] Jonathan Dowling

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Re: [2020-06-26] Jonathan Dowling

by joeanderson1 » Thu May 13, 2021 4:13 am

Thank you for the pdf file! I'll share this with my brother in Baltimore, he's a fan!

Greetings!

Re: [2020-06-26] Jonathan Dowling

by DangerousPenticorn » Tue Aug 11, 2020 10:38 am

Sorry just noticed I made a calculation error... the (5/6)^120 isn't correct. It's not because it's not-anti-correlated and you're measuring opposite results that you would notice it. you can be measuring 6 and 12 while the readings are 5 and 10, so you get a double negative as you expect...
The chances of not a single positive appearing when measuring opposite sides in the third-form generator is I guess (1-1/6*(1/12+1/12))^120 or about 3.4%.

This also shifts the generator in favor of producing more random results so the optimum would shift to generate 2 random result every 5 runs with a likelihood of throwing 0 single-positive opposites of 0.025% and a likelihood of throwing 9 double-positive non-opposites of 0.26% with a total likelihood of 6.5*10^-7. Still this isn't very likely, but is it enough to throw all logic as "locality" and "causality" in the garbage bin?

Re: [2020-06-26] Jonathan Dowling

by DangerousPenticorn » Tue Aug 11, 2020 10:06 am

@Recovering
Yes, but only if the results in those tables are incorrect. If the premise is: "They are correlated, but ONLY if you measure the direct opposites" THEN you have a new game.
a Random generator would be able to create seemingly random results that are actually entirely predetermined before you measure it (e.g. some consecutive numbers of PI in a dozenal system), also as they are entangled, it can create those anti-correlation aspects at the moment of Creation.
However it can't at the same time guarantee random results for all non-direct-opposites. Or it can create 100% random results for all non-direct-opposites, but then it can't guarantee 100% correlation of direct-opposites.
Let's say that Alice's watch is "predetermined" to collapse into the 12-hour dial. In that case Bob's watch can't be BOTH predetermined to collapse to the 6-hour dial AND have a 1/12 chance to collapse into any other dial.

A third possibility is a random predetermined generator that generates mostly opposite results, but also the occasional non-opposites (e.g. 10 and 5), however then by happy little accident the sampling must be done so that you NEVER take opposite readings when the generator produced a non-opposite.

The chance of hitting a double positive when you're reading non-opposites is 1/144.
So let's say this third-form random generator creates an anti-correlated result in 5/6 cases and a random not-anti-correlated result in 1/6 cases.
And let's say you're doing an experiment with 1440 tests (10 times every configuration). Quantum mechanics then predicts 10 double positives for opposite readings, 0 single positives for opposite readings and 110 double negatives for opposite readings. At the same time there should also be about 9 double positives for non-opposite readings. Let's say the result is exactly as Quantum mechanics predicted. Then you still can't rule out the third-form random generator.
=> Even though the random generator only produces random results in 1/6 cases, it could still throw 9 positives in 1320 runs where you're measuring opposite sides (although mean expected value out of 220 cases is 1.5 and standard deviation is 1.2). It is ONLY 6 standard deviations away so there's still a 0.00000006% chance left, that's not 0.
=> Even though the random generator produces random results in 1/6 cases, it could still throw 0 positives in 120 runs you happen to be measuring opposite sides. (thats 5/6^120 or 0.00000003% likely to happen).
So I'm not that good at statistics but I guess you can multiply both odds for them to be happening together and you get a chance of 2*10^(-19) chance of this scenario with a third-form predetermined random generator. The odds don't really get better if you vary this 5/6 to higher or lower value.

I guess the math formula is doing something like this calculation? although it gets more complex if there's false positives or negatives when there's equipment failure...

Re: [2020-06-26] Jonathan Dowling

by RecoveringCatholic » Mon Aug 10, 2020 4:00 pm

@Dangerous:

I had the same problem. As far as I can tell, that particular thought experiment could have been replaced by a reasonably robust random number generator.

The other problem I had with the text is that while Zach mentioned it was "just mathematical enough," it actually doesn't seem mathematical at all. Perhaps I missed them, but I didn't find any equations at all in flipping through the text, which was something of a disappointment.

We're just told that the expermenter has a computer program that computes the statistics but there's not indication of what the statistical model is which would separate, say, a simple random number generator from the quantum-entangled atoms in the two "watches."

Perhaps that's later in the book but I sort of got lost at that point as I felt that I was supposed to take this more or less "on faith," which seems a bit unexpected in a scientific publication, even one aimed at a non-domain-specialist audience.

Re: [2020-06-26] Jonathan Dowling

by DangerousPenticorn » Mon Aug 10, 2020 7:36 am

I've ordered the book a while ago but only just started reading it now. Problem with reading a book about quantum mechanics is I'm constantly wondering: Am I missing something or is there an error in the book? (o~o)
Ex.1: p16 table 1.1: run 2 and run 10: it mentions 10 and 5 but those aren't 6 hours apart...!?
Ex.2: p22 table 1.2: run 7 and run 8: how come Alice and Bob can have both a visible hour hand if they are NOT 6 hours apart? I thought the whole point was that if either is measured, the other would collapse at 6 hours apart? It is not just in the table it is also mentioned in the text. Did the premise of the quantum-paired watches change into: if you read 6 hours apart they're reversely-correlated, if you read anything not 6 hours apart it is completely random. If this is indeed the case I think I get the whole point of why we can 'disprove' the hidden variable theory by doing a lot of tests. But then this premise change is not well explained.
Also p21. The experiment says Alice and Bob have to check the watch at roughly the same time, what does that mean? If the collapse of state is instantaneous, does it matter if you only check the 2nd watch an hour later? Or is the pairing also time-bound and will the watches produce opposite results only when looked at the exact same timepoint? (And in that case what is 1 timepoint)?
... I have the feeling I'm close to understanding something, but I miss a few steps...

Re: [2020-06-26] Jonathan Dowling

by RyanW » Sat Jul 11, 2020 1:48 pm

RecoveringCatholic wrote:
Thu Jul 09, 2020 12:17 pm
I'm not sure whether the PDF would be any easier to deal with. I suppose it might depend on the PDF reader involved. In my copy of the PDF, the notes aren't hyperlinked, so you'd have to scroll backwards and forwards.
I think the ideal method of presentation might be notes as hovertext. It would be slightly more challenging to implement in a physical book, however.

Re: [2020-06-26] Jonathan Dowling

by RecoveringCatholic » Sat Jul 11, 2020 1:39 pm

The NSA's existence was originally classified but that was way back in the Truman Administration and not officially acknowledged until the 1970s. It was, however, a fairly open secret and often jokingly referred to as "No Such Agency."

The Church Committee in the mid-1970s certainly openly discussed its existence by name.

In a previous gig, I personally installed some software I'd developed on one of the NSA's IBM mainframe computers in the early 1980s -- I'd say around 1983 or 1984 -- and I was not sworn to secrecy (I did my work on a non-classified system and there were no secrets involved other than how really horrible the software was). I did not carry a NSA clearance so saw or heard nothing of particular interest and I did require a 'baby sitter' with me at all times.[1]

At another gig, I had a colleague who was a former NSA mathematician and, again, there was nothing secret about that, though I could always get him into a bit of a dither if I started asking him questions about number theory.

For a number of years NSA people didn't acknowledge their employer.

You could, however, always tell the NSA attendees at conferences because instead of a university or company affiliation, their badge would just say "US Government." I think CIA were more open (though I won't swear to it)>

I seem to recall seeing a few of those badges at conferences in the early to mid-1980s but that's a bit hazy.

I'm not certain when that policy changed, but that might be the source of Dowling's confusion.

[1] A Dowling-like digression: I also consulted on a nonclassified project at Lawrence Livermore Labs and not only was I escorted everywhere, including the restroom, but when I was in the restroom, they would put a little sawhorse in the doorway warning that an uncleared person was inside. Similarly, at the NSA, as I was escorted through the building, along the way, my escort would flip a light switch which would start a rotating flashing yellow light mounted to the ceiling warning of the presence of a non-crypto-cleared person. All very bizarre and entertaining, in a "spooky" sort of way.

Re: [2020-06-26] Jonathan Dowling

by Jack Roland Nolan » Fri Jul 10, 2020 4:48 pm

I found and downloaded the PDF from Dowling on the Killer App. I am a computer nerd and have been one since my Junior Year in High School (1963). Dowling mentions that the NSA has been a classified agency until the 1990's. In college, (Drexel), I and several of my classmates were interviewed for a co-op job at the NSA and we were never told to keep its existence secret. I was not offered the job, but I've told this story several times. Many times, the person I've told the story to has acknowledged that they knew of the existence of the NSA, so I wonder where Dowling got his information.
Sorry that your friend passed away so young.
(And, yes, I am able to understand enough of it to get by.)

Re: [2020-06-26] Jonathan Dowling

by RecoveringCatholic » Thu Jul 09, 2020 12:17 pm

I just got my copy of Dowling's book Schroedinger's Killer App and I can see why Zach liked it.

I'm just about through the first chapter (and admit that I don't get the whole "verifiable quantum entangled clocks" model entirely but that's a subject for another forum, I suspect).

If I had a criticism, it would have to be "too many notes" -- endnotes, that is.

A lot of books have endnotes, of course, usually just bibliographic references which the casual reader can largely ignore. Dowling, however, interpolates all sorts of wisecracks, digressions, and little stories (including one about getting stared down by Paul Dirac in a public lecture) that actually are interesting.

I wish that he or his editor had separated the bibligraphic reference from the digressions by using actual on-page footnotes for the digressions while reserving the endnotes for the others. I find I have to flip back and forth between the main text and the end notes constantly and actually have to have two bookmarks so I don't lose my place.

I'm not sure whether the PDF would be any easier to deal with. I suppose it might depend on the PDF reader involved. In my copy of the PDF, the notes aren't hyperlinked, so you'd have to scroll backwards and forwards.

Anyhow, other than that quibble, highly recommended. I have no idea whether I'm smart enough to end up with any new understanding of quantum mechanics (the "Two Beers" model is not applicable, since I stopped drinking beer a while ago).

Re: [2020-06-26] Jonathan Dowling

by Staid Figure » Fri Jul 03, 2020 7:31 am

Ain't been the tradition ascribing novations to staid figures? E'en now, such misfacts.

Re: [2020-06-26] Jonathan Dowling

by Guest » Mon Jun 29, 2020 12:37 am

^ My mistake, reading more closely Sunzi Suanjing is not the same person as Sun Tzu he was just named after Sun Tzu.

So then you have Sun Tzu, who wrote "The Art of War"

Sunzi Suanjing who wrote "The mathematical classic" and was apparently named after Sun Tzu, because in chinese Sun Tzu is spelled as Sunzi: https://en.wikipedia.org/wiki/The_Art_of_War

and Zhang Qiujian Suanjing who also wrote a book called "The mathematical classic".

Re: [2020-06-26] Jonathan Dowling

by Guest » Mon Jun 29, 2020 12:30 am

SwervingLemon wrote:
Fri Jun 26, 2020 6:12 pm
Did he really attribute the Mathematical Classic to Sun Tzu?

It was written by Zhang Qiujian and was compiled in the fifth century.
No actually it was fine there are two "the Mathematical Classic"s'

One actually by Sun Tzu 3rd-5th century : https://en.wikipedia.org/wiki/Sunzi_Suanjing (Sunzi Suanjing is the same person as Sun Tzu apparently)

One by Zhang Qiujian Suanjing:
https://en.wikipedia.org/wiki/Zhang_Qiujian_Suanjing

Props for knowing about it though. I'm Chinese and I didn't know xD im sorry

Re: [2020-06-26] Jonathan Dowling

by SwervingLemon » Fri Jun 26, 2020 6:12 pm

Did he really attribute the Mathematical Classic to Sun Tzu?

It was written by Zhang Qiujian and was compiled in the fifth century.

Re: [2020-06-26] Jonathan Dowling

by RecoveringCatholic » Fri Jun 26, 2020 5:27 pm

I have to assume that it's free and legal -- CRC Press/Taylor & Francis is pretty stringent about copyright violations. And it's on the late author's own site.

Anyhow, I've ordered the book from CRC Press so my soul is safe.

Re: [2020-06-26] Jonathan Dowling

by rmsberger » Fri Jun 26, 2020 3:50 pm

I found the free PDF, but I didn't download it yet. Wanted to know if it was legal first. (If I'm gonna go to hell, it's going to be for something better than bootlegging a book I could afford. :lol: )

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