The Bohr-Einstein Debates, With Puppets

I'm just at the start of it, and it's already amazingly amusing. This was a great campaign.

Puppy puppets!

The Bichon as Einstein was inspired. Love it!

A most amusing summary of the debate. In particular the gargoyle Pauli made me LOL, as the youth of today would have it.

However, I must object to "Bohr was correct" as an ending. How can you say that someone who didn't respond to any of the actual objections being raised by E and EPR during the debate and who wrote an incomprehensible paper, the meaning of which is still debated, was correct about any of this? It may be true that the local hidden variable picture that seems to be implied by the EPR paper has essentially been falsified, but that doesn't mean that we have all become Bohring Copenhagen dogmatists as a result. If anything, a large number of physicists would now agree that there is a measurement problem and many of them subscribe to more realist interpretations, e.g. many-worlds, as a result.

The bottom line is that there are more than two sides to this debate and both Bohr and Einstein were defending incorrect positions, although Einstein's attacks showed more insight than Bohr's defense. The only thing we can say about Bohr's contribution to the debate is that we ended up with a couple of neat examples of the uncertainty principle that are pedagogically very useful (ignoring objections to the naive use of the Energy-Time uncertainty relation).

This may be an entirely silly question, but.

In Young's double-slit experiment, we know that observing the electrons caused them to behave differently. What was the apparatus used to observe the electrons, and how did it collapse the wavefunction?

However, I must object to "Bohr was correct" as an ending. How can you say that someone who didn't respond to any of the actual objections being raised by E and EPR during the debate and who wrote an incomprehensible paper, the meaning of which is still debated, was correct about any of this?

He was correct in that the measurement results are correlated in a non-local way, which is, I think, what he was struggling to say in a way that would sound halfway palatable when he wrote that godawful "possibilities of unambiguous interpretation" stuff. I doubt he was all that comfortable with the idea of non-locality, either, but his insistence that the only things that matter are things that can be measured was closer to the truth than EPR.

I do think that, as you say, Einstein's approach to the whole business showed more insight into the problems than Bohr's responses. Really, though, the only person who comes out of the whole thing looking good is John Bell.

Basically, though, I went with "Bohr was correct" because it's short, and the whole thing had already run to 18-ish minutes.

Katharine: In Young's double-slit experiment, we know that observing the electrons caused them to behave differently. What was the apparatus used to observe the electrons, and how did it collapse the wavefunction?

The usual detector for this sort of experiment is a fluorescent screen, that emits a pulse of light when it's hit by an electron. It's basically like an old monochrome tv or computer monitor, only much more sensitive.

"Collapse the wavefunction" is kind of a loaded term, and some people who prefer different interpretations would object to it. The basic idea, though, is that the electron hits a screen and triggers a process whereby a large number of molecules emit photons, in a way that can't easily be undone, and produce an effect that can be seen on a macroscopic scale.

I am terribly disappointed in you for not using a Great Dane puppet for Niels Bohr. Terribly.

If if were theoretically possible to shrink down to subatomic scale and observe this, would the same thing happen if we used only eyes to observe it?

I am terribly disappointed in you for not using a Great Dane puppet for Niels Bohr.

If they had had a Great Dane puppet at the Open Door, I would've gotten it. The Lab was the best I could do.

If if were theoretically possible to shrink down to subatomic scale and observe this, would the same thing happen if we used only eyes to observe it?

This is a tricky subject, but the answer is approximately "no."

The signature of a measurement in quantum mechanics is that it's a macroscopic phenomenon, involving very large numbers of particles. This happens thanks to a process known as "decoherence," which depends on interactions between the thing being measured and a large environment, most of the details of which remain unmeasured. Those unmeasured interactions are key to destroying the quantum character of the system being measured, and ensure that you only detect a macroscopic object either here or there, and never here AND there at the same time.

If you were shrunk to microscopic size, but somehow still contained 10^27 atoms (or whatever), then you would still see the same effect. A real microscopic apparatus, though, which only contains a smallish number of particles, can become entangled with the system being measured in a way that allows you to still see quantum effects.

I'm curious how Niels Bohr's responses to Einstein's objections would compare to more modern responses. Would a modern physicist say the same thing about measuring the mass of the box with a spring?

I'm curious how Niels Bohr's responses to Einstein's objections would compare to more modern responses. Would a modern physicist say the same thing about measuring the mass of the box with a spring?

The problem with Bohr's responses wasn't that they were incorrect, but that they were non-responsive-- that is, they were perfectly good answers to questions other than the ones Einstein was asking. The stuff with the box on the spring is exactly correct, but it doesn't address the problem Einstein was actually pointing to. Bohr was kind of fixated on issues of uncertainty and complementarity, and tended to interpret everything in that light (including social and political problems, later in his life).

A few days ago, I tagged an article by Don Howard for the daily links dump that lays a lot of this out in detail. I also recommend Louisa Gilder's The Age of Entanglement and David Lindley's Uncertainty, which served as the source for most of the dialogue in the puppet show.

I have to say, this far surpasses mutton-chop whiskers.

Also. "beyond the scope of this puppet show" is my new favorite phrase.

I had to suppress LOL when I got to 1:50 in the video (wondering which ones in the audience were Lorentz, Curie, and Dirac), then had to stifle it completely at 2:12 when I heard the accent - and then read your apology to German speakers! And your choice of Pauli, that was TOTALLY inspired. I see an appearance of this clip in Big Bang Theory (e-mailed to Sheldon in violation of one of his laws) sometime in your future.

However, I have to complain that there was no mention of the bigger problem posed by having identical Emmy puppets play the protagonists in this episode, namely whether Emmy is a fermion or a boson.

The responses to Bohr's final incomprehensibility were spot on.

So how much do people need to donate for you to continue?

(Sorry, I donated mostly to Cosmic Variance. Though HP did send me $500 to distribute afterwards, which went to Grrrlscientist, since CV was all done by then.)

First i am @ the start of this campaign and enjoying it. Second like Miller said I'm too curious how Niels Bohr's responses to Einstein's objections would compare to more modern responses. Great post, anyway! I am a college sophomore with a dual major in Physics and Mathematics @ University of California, Santa Barbara. By the way, i came across these excellent physics flashcards. Its also a great initiative by the FunnelBrain team. Amazing!!!

I'm curious if SteelyKid has any thoughts on the increased puppet activity at home? I'm guessing she will get the puppets now that their performance has been captured on video.

I like the German accent :-) You could try to make the consonant's more pronounced for more effect. But you should really get more puppetsa (and post more puppet-videos).

CCPhysics, Emmy is neither a fermion or a boson. Emmy is Noether.

As for "beyond the scope of this puppet show," it's about to become more widely used. I have learned that, as a way of improving the accessibility of the kind of result formerly published in Physical Review Letters to a wide audience of physicists, the traditional Letters format will be replaced by an online repository; only results presentable in a four-minute puppet show will be accepted by the Physical Review Puppet Seminar Archive (PRPSA).

Whoa! That was great. I love the Librarian as Bell. Maybe next year we'll get Bell's work as a puppet show for our Donors Choose reward!

I'm wondering who Muk Muk was. Probably Planck.

you make the classic puppet error of closing the puppet's mouth when sound should be coming out instead of opening it. should work on that. also why do you make bohr's mouth move while you are narrating?

I'm wondering who Muk Muk was. Probably Planck.

I didn't have specific identities in mind for the rest of them. I just grabed stuffed animals of approximately the right size.

Muk Muk was purchased for SteelyKid at the Toronto airport on the way home from Q2C. I wanted to include the armadillo I bought her in Houston, but couldn't find it.

also why do you make bohr's mouth move while you are narrating?

Because I always move my hands while talking, and can't stop myself. I barely managed to keep from waving the puppet around in the air.

(Some of my teachers used to speculate that if you tied my hands to my sides, I would be unable to speak. None of them ever tried it, but I'm sure a couple were tempted.)

Most importantly, why is Emmy a German Shepherd in the puppet show and some other breed (a black lab?) on the book cover? And wouldn't that have neatly resolved the fermion/boson issue?