Hacker News Reader

Comment by davesque | Hacker News Reader

Thanks for the great explanation. Serious question: Can I ask how you happen to know so much about this subject?

Years of practice :-)

Seriously though, I don't actually know much about QM, I only know the One Thing that makes the rest of QM easy to understand (kind of like knowing Lisp makes the rest of computer programming easy to understand).

In case you want to know that One Thing, it's written up here: http://www.flownet.com/ron/QM.pdf

There's also a movie version: https://www.youtube.com/watch?v=dEaecUuEqfc

Cool, thanks for the info.

You may want to also look for an article by N. David Mermin "Is the moon there when nobody looks"

Just be aware that while Dr. Garret is very smart (and very accomplished with software) he is not a physicist. When this talk first came out I asked a couple people who do know QFT in detail about it and they were quite dismissive.

It's true. I'm not a physicist. I have never claimed to be a physicist. The only contribution I have ever claimed is a pedagogical one.

When I first wrote the paper 15 years ago I submitted it to Physics Today. It was rejected, not because it was wrong, but because the reviewers thought that it was nothing new, that everyone already knew this stuff. Since then the physics community has bifurcated rather neatly into two camps: the ones who agree with the PT reviewers, and the ones who think I'm a "category 5 loon" (that was Lubos Motl's term). Personally, I think the existence of people like Motl and your anonymous "dismissive" QFT experts -- and the fact that I can still stump card-carrying physicists with the EPRG paradox -- falsifies the hypothesis that "everyone already knows this stuff."

I will also say, because I'm feeling rather annoying by all this, that in 15 years no one has ever pointed out any actual mistakes in the paper (except for a few typos).

I'm not qualified to adjudicate this, but I would point out that painting yourself as revealing a conspiracy doesn't do you any favors IMO.

Edit: downvote me all you like, but at least be accurate. I'm referring to the title of the tech talk video linked several times in this thread: "The Quantum Conspiracy: What Popularizers of QM Don't Want You to Know"

There was no conspiracy mentioned. Just people disagreeing about a hard subject.

There is no conspiracy described in GP, only human politics as usual.

You obviously didn't watch even the first minute of the talk because the very first thing I say is that the title is tongue-in-cheek and there is no conspiracy.

I did, though it's been several years. Making an inflammatory statement, then denying it as a joke is a common mild double bind, one that's best avoided. I'm not speaking toward your intentions as I obviously don't know them. I'm just pointing out that particular rhetorical form isn't doing you any favors, again, IMO.

I prefer to think of it as a marketing strategy. And I think it has actually been fairly effective. That video has had over a million views.

As a semi-random person with little connection to you or your critic, I just want you to know their comment just reminded me to critically think about what you're saying, not to think it was wrong or misleading.

Hi, I'm considerably less of a physicist than yourself :) I did watch your google talk video, and have to thank you for an interesting presentation that introduced me to a couple of new perspectives on quantum interpretation. I'm utterly unqualified to have an opinion on the topic, but enjoy thinking about it sometimes.

So I just wanted to ask in respect of "no one has ever pointed out any actual mistakes" - have you seen the stackexchange discussion at http://physics.stackexchange.com/questions/208609/does-the-f... , and do you have any comment on the assertion there that your statement of EPRG misses the point that "even if Alice does let her system produce interference, the other system will not produce interference either"?

I have not seen this particular exchange, but it is typical of people who have missed the point. Yes, of course the EPRG paradox doesn't work. That's the whole point. It's a straw man, designed to draw attention to the fact that there is something wrong with QM pedagogy.

The thing that people who critique my work generally miss is that it is not about physics, it's about pedagogy. It's about how the physics is explained. Everyone agrees on the physics. It's the explanation that is at issue. The whole first half of the talk is the problem statement.

(God damn this is annoying: "I'm afraid I won't have time to critique whatever it is he says in the second half of the video." Well, the second half is where I explain why the EPRG paradox doesn't actually work. By the time I gave that talk I already knew that people got this wrong, so I went to great lengths to highlight the fact that EPRG was a straw man. And then people jump into the middle of the video, see the story out of context, and say "This is wrong." Well, duh, of course it's wrong. That's the whole fucking point!)

Heh, thanks for the explanation, and sorry for apparently ruining your day :)

I did suspect that "Garret then claims that this can be used for superluminal communication" missed that you were using this as a kind of reductio, but I then took it to mean that your reductio was not working how you expected it to. Probably I should re-watch the video - it's been a couple of years.

You didn't ruin my day, it actually feels good to vent every now and then. :-)

> your reductio was not working how you expected it to

Actually, it pretty much works exactly how I expected, and has for 25 years (I started down this road in 1990 when the EPRG paradox first occurred to me. It took me ten years to find someone who knew the answer.)

The problem is when people look at EPRG out of context and think that my thesis is that I've invented FTL and therefore I am the World's Greatest Physicist. (And now some moron is probably going to cite this very comment and say that I've claimed to be the Worlds Greatest Physicist because they saw that I wrote "... I am the World's Greatest Physicist" and they don't have time to read the part that they elided.)

I watched your video. Viewing measurement and entanglement as the same thing or closely related is ineresting, and the EPRG experiment is clever. I've never seen that before. Thanks for that! I need to think about it for a bit.

But I think you give too short a shrift to Many-Worlds because it's not intuitive to you. Plenty of things about QM are not intuitive; I don't think that's sufficient reason to reject it.

I didn't reject it (at least I don't think I did -- it has been a while since I watched the video). I believe I said that both "many-worlds" and "zero-worlds" were equally legitimate -- only "one-world" (Copenhagen) is untenable.

[UPDATE] Yes, my recollection is correct. Go watch it again starting at the 58 minute mark or a little earlier.

During the end questions yes, but at timestamp 43:20: "But I personally find [Many-Worlds] takes a heavier toll on my intuition than I'm willing to concede."

OK, well, I think it's a little unfair to characterize that as a "rejection." But my thinking has evolved a bit in the past five years. The difference between zero-worlds and many-worlds is the difference between taking a personal point of view or a God's-eye-view. God can see the many-worlds, but I can't, so it makes more sense to me to assign a privileged status to this world, the one I live in. But then I have to make my peace with the fact that this world is not as it appears to be, and I do that by thinking of it as a (very high quality) simulation. But that just my personal approach. Reasonable people can (and do) disagree.

didn't do the math, but sounds plausible though I know barely anything of quantum mechanics.

just to confirm my interpretation, its saying that:

- fundamentally the universe is governed by quantum mechanics

- classical physics doesn't truly exist

- the classical physics we see and intuit can be explained by entropy (information theory) of the quantum state

- measurement and entanglement are the same in the sense that both imparts "information" into the system. this in effect acts as a "filter", an example of which is the double-slit experiment where the waves are "filtered" to particles when being measured

- our conscious mind is a classical construct so its naturally difficult to intuit quantum laws

is that mostly correct? also, how popular is this theory in the physics community?

> is that mostly correct?

Mostly.

> also, how popular is this theory in the physics community?

Not very. The fashionable way to think about this stuff is something called "decoherence" which really amounts to the same thing but phrased in different terms.

Thanks!

so if i were to do further research into this, I would use the keyword "decoherence"?

also not being a physicist, could I naively think this would be a good candidate for the "theory of everything"?

> so if i were to do further research into this, I would use the keyword "decoherence"?

Decoherence, relational quantum mechanics, quantum information theory, the Von Neuman measurement model -- all of these turn out to be the same thing.

> also not being a physicist, could I naively think this would be a good candidate for the "theory of everything"?

No, the "theory of everything" refers to the unification of quantum mechanics and relativity. Completely different topic.

Thanks for clarifying my misconception

You bet.

Didn't realize it was you, Dr. Garret. Thanks a lot for taking the time to chat with us about this.

My pleasure :-)

Reply on news.ycombinator.com