Schrodinger's Cat

[Brooks R]

No: HPFGUIDX 1328

--- In HPforGrownups at egroups.com, "Denise" <gypsycaine at y...> wrote:
> Schrodinger's Cat 
> 
> Could you explain what this is?
> 
> Thanks!


You need to hire a good Quantum mechanic for that.

Seriously, Schrodinger proposed this thought experiment in an attempt 
to explain how Quantum phenomena are statistical in nature and to 
demonstrate one implication of uncertainty.

The basic postulate is you have a box, in which is a single atom of a 
radioactive isotope, with a half-life of exactly one hour.  This
means 
that there is a 50-50 chance that the particle will decay within that 
one hour.  You surround the particle with a perfect detector such
that 
if it decays, that fact will be detected.  You then make the detector 
trip a switch if the decay is detected, which will open a valve that 
will release cyanide into the box.  

You put a cat in the box.

Assuming you cannot hear or feel the cat moving around, meowing, or
in 
any other way detect the state of the cat, and that you have no 
external indicator as to whether the detector was activated or 
not, you wait an hour and then open the box.  Did the particle decay 
or did it not?  Did the cat die or did it not?  The answer is that it 
is impossible to know until you open the box.  Is the cat alive or 
dead?  It is both at the same time, because both are states of the 
universe that co-exist *until an observation is made*.   This is 
called "superimposed states".  When you make an observation, the 
superimposed states collapse leaving only one result as the 
"winner".  At the mathematical descriptions of elementary particles 
level the universe really does seem to work that way.  The thought 
experiment is an attempt to show an effect at a macroscopic level of
a 
quantum mechanics reality:  at the quantum level the universe
operates 
by blind statistics.

(The experiment as described is technically impossible because at the 
time it was invented, there was no way to put in a single radioactive 
atom, although there is now; and there will probably never be a 
perfect detector).

-Brooks