This is topic Argh! Quantum Physics! in forum Books, Films, Food and Culture at Hatrack River Forum.


To visit this topic, use this URL:
http://www.hatrack.com/ubb/main/ultimatebb.php?ubb=get_topic;f=2;t=042957

Posted by Blayne Bradley (Member # 8565) on :
 
Can anyone quote for me what the theotetical schroeder's cat experiment was? Its not on wiki and i cant find it conveniently on google.
 
Posted by TheGrimace (Member # 9178) on :
 
schroedinger's cat

spelling FTW
 
Posted by TheGrimace (Member # 9178) on :
 
actually, even misspelled the second google hit gives you a run-down of the whole thing...
 
Posted by Blayne Bradley (Member # 8565) on :
 
wow, I'm not sure I got/understood it.
 
Posted by TheGrimace (Member # 9178) on :
 
the argument of schroedinger's cat or my responses?
 
Posted by Blayne Bradley (Member # 8565) on :
 
the cat.
 
Posted by King of Men (Member # 6684) on :
 
It's worth bearing in mind that Schroedinger actually intended his cat as a counter-example. We know perfectly well that real cats (and other macroscopic objects) are not in superpositions of alive and dead; so somewhere between the quantum effects in the Geiger counter, and the biological effects in the real cat, a transformation takes place. Schroedinger wanted to understand that transformation, still one of the major mysteries of quantum mechanics. People just misunderstood what he was trying to say.
 
Posted by Princess Leah (Member # 6026) on :
 
Read Douglas Adams' Dirk Gently's Holistic Detective Agency. Much simpler explanation found therein, plus brilliant wordplay and an amusing plot.
 
Posted by TomDavidson (Member # 124) on :
 
A (very) basic (and thus inaccurate) summation:

One of the weirder principles of quantum physics is that certain subatomic particles can not only exist in two or more different states or locations indeterminately but in fact must exist in them simultaneously. (The most classic example is the fact, now proven by experiment, that photons travel as both particles and waves until "observed" -- that, in other words, as long as their state is indeterminate, they occupy both states at once.)

Many physicists were unhappy with the ramifications of these (at the time) hypothetical theories. To demonstrate how ridiculous he felt this way, Schroedinger advanced his own example.

Consider, he said, a cat in a box. The box also contains a Geiger counter (to detect radiation) attached to a vial of poison gas and a radioactive lump. At any time, the lump could emit an alpha particle and trigger the Geiger counter, which would release the gas and kill the cat.

But -- and here's the kicker -- until the box is opened, from the standpoint of an observer outside the box, an alpha particle is both decayed and not decayed. Which means the cat is both alive and dead.

Schroedinger's point was that this was ridiculous, and that clearly subatomic quantum interactions broke down on a larger scale. Interestingly, a "macroverse" theory has become popular lately that suggests a possible resolution. But we also know that quantum mechanics DOES seem to have a point -- largely determined by gravitational mass -- beyond which it doesn't seem to apply to larger bodies. (The classic example here, by the way, discusses how tiny the wavelength of a bowling ball would be. Seriously. What's interesting is that there's a guy out there trying to get measure the wavelengths of tiny but still appreciable masses. If he can do it, we'll have further evidence that all matter is in fact made up of waves.)
 
Posted by Lyrhawn (Member # 7039) on :
 
Nicely broken down Tom.

I actually understood that.
 


Copyright © 2008 Hatrack River Enterprises Inc. All rights reserved.
Reproduction in whole or in part without permission is prohibited.


Powered by Infopop Corporation
UBB.classic™ 6.7.2