Shrodinger's cat is "in limbo" said the textbook used in the first physics class I enrolled in, which was at the University of Arkansas at Little Rock, in the year--well never mind the year. The textbook was Physics for the Life Sciences, by Alan Cromer. I lost the textbook or maybe someone stole it and I've thought since then that whenever I find that book, that will be when I solve the paradox of Schrodinger's Cat. It's been a long time, and the textbook has not reappeared, so it's becoming likely I will not solve the paradox.
The cat paradox was put to good use in the movie A Serious Man. I'll be discussing the movie and the cat problem in this blog. I'll start with a problem that occurs in the classroom dream scene in the movie, a problem you might have noticed. Larry writes an equation on the board that contains the square root of <P>^2 - <P>^2. It's quite easily seen to be zero--something minus itself--but of course his answer isn't zero.
After the class leaves (one of the Coen brothers can be seen getting up from a front row seat) and Larry and Sy are talking (Sy would be a dybbuk in the dream, by the way) the equation is on the board behind Larry, but now it's been corrected! Now underneath the square root is <P^2> - <P>^2, which is what it should have been in the first place. This is an expression from statistics, not just from physics. I'll come back to it later. Another thing about that scene is that Sy calls mathematics the art of the possible. Larry is a little flustered by this, and says he thinks something else is the art of the possible, but he can't remember what. I could well identify with Larry in that scene, partly because the mathematical thing he wrote on the board is called something, but right now I can't remember what... However, I did look up "the art of the possible." It's politics, not math, so Larry was right, but couldn't "prove" it at the time.
