Thursday, April 17, 2008

What Schroedinger Never Understood

The cat knows.

There. Now can science-fiction authors please shut up about the experiment?

(The preceding tiny rant was brought on by 'Dirk Gently's Holistic Detective Agency', one of the umpteen billion sci-fi books that brings up "Schroedinger's Cat". Although at least Douglas Adams had the decency to do it as a joke, and to point out that the experiment wouldn't work.)


Eric TF Bat said...

I always thought that was a bit of a loophole too. Maybe the point is that anything that the experimenter doesn't know about remains unknowable from his/her point of view. So the cat is in a superposition of quantum wossnames for the experimenter even while its continued existence or lack thereof is completely unambiguous to the cat. Or something.

Or maybe Shrödinger was a dog person.

Anonymous said...

I think that Schroedinger was well aware that the cat, and the geiger counter for that matter, are observers. The point of Schrödinger's cat was to point out specific problems with the Copenhagen interpretation of quantum physics when applying superposition at a macroscopic scale. It was the sci-fi writers who took the idea and ran with it.

Matt said...

Exactly what Ted said. Schrodinger's Cat isn't supposed to be a proof, or representation of quantum physics. It was an absurd example meant to point out his concerns about the theory. But it's such a fun metaphor, I suspect authors can't help themselves.

Callahan said...

I think the truth is, we're all just in love with the idea of physicists randomly gassing unwitting cats.

That said, we need more sci-fi novels based off the Geiger-Marsden experiment. I don't know how you'd do it, but I always thought that was a particularly badass moment in atomic physics.

John Seavey said...

To forestall further comments: Yes, I know Schroedinger understood it. The title of the post is facetious. But I do get very sick of people not understanding quantum theory properly because all they've ever heard about is "Schroedinger's Cat", and thinking that there's something special about human consciousness, that our perceptions define reality or some such.

When in fact, as Ted said, not only does the cat know, but the geiger counter knows. The waveform collapses as soon as it is measured, not as soon as a human being observes it.

I just wish Schroedinger had never bloody brought it up, is all. :)