Can Anyone Explain, In Laymans Terms, What Role Schrödinger's Cat Played In The Development Of Quantum Theory?

[sandyRoe]

?

[aelmpvw]

just googled it sandy and now my brain hurts

[sandyRoe]

I noticed a Google doodle celebrates his birthday today. I suspect there aren't layman's terms to explain where he was going.

[factor-fiction]

I'm uncertain too, on principle

[mikey4444]

Sandy...I am not sure I can begin to understand it but I found this on wiki.

http://en.wikipedia.org/wiki/Schr%C3%B6dinger's_cat

[Alston]

Does this help.?:-

http://en.wikipedia.org/wiki/Schr%C3%B6dinger%27s_Cat

Al.

[douglas9401]

Where's Professor Cox when you need him?

[emeritus]

This explains it quite well (I think)

http://www.youtube.com/watch?v=IOYyCHGWJq4

[humbersloop]

Schrödinger's cat walked into a bar. And didn't.

I'll get me coat

[jake-the-peg]

Schrodingers cat was actually a thought experiment designed to disprove a key part of Quantum Mechanics - Ironically these days it's a key element of it!

Certain QM systems depend on whether or not they are observed for example if you fire electrons through two slits they will behave like waves and produce a pattern of dark and light bands characteristic of waves.

If you actually try to measure which slit an electron goes through the pattern will change showing electrons as particles.

Observing an event changes it!

The explanation is the particle is in both states simultaneously until it's observed when one state or the other crystalises out

Schroedinger didn't like this any more than Einstein did and contructed the thought experiment to try to show it was absurd.

The familiiar set up whereby the cat is in the box with the unobserved radioactive source until it's observed the source is decayed and undecayed and hence the cat it both alive and dead.

The 'resolution' of this depends on the interpretation of QM that to ascribe to - there are several. The alive and dead is Neils Bhor's 'Copenhagen' interpretation. In the 'Many worlds' interpretation there is aUniverse with a live cat and another with a dead one - when you open the box you discover which Universe you are in.

It's impossible to prove which interpretation is 'correct' so IMHO it's a bit of a game played by theoreticians.

I'm sure Jim thinks it much more important than I do

[mushroom25]

when my group were skiing in Finland this year, we had "Schroedinger's Kitty" - which was a box that might - or might not - have contained sufficient funds for a round of drinks at the bar that night.

[weecalf]

thought it was a film sandyRoe when I first read it

[Peter Pedant]

Emeritus
Many thanks
I agree the Fihziks viddy I thought really good -
and toook it further than I am accustomed
(Further than Schrodinger intended)
but yeah it bears witness how QT developed as a result.

excellent

[rowanwitch]

I reckon he walked across the keyboard when Schrodinger was working and he thought oh that makes sense... The cat was called Quantum hence Quantum's physics

[Peter Pedant]

Hi mushy ! of course - obvious really....

when all the banks went wonky of a day - software probz

when you thought you were in credit and the bank said you werent,
were you ? [in credit that is] {scrrodinger's bank}

[Peter Pedant]

crystallise - I love that word

In Thompson v Foy 2009, do you realise that Mrs Julie Foy's undue influence would not 'crystallise' out until she had actually misapplied the funds she should be giving Mrs Thompson ? Just having it in the bank and saying no wasnt enough. His lordhip didnt mention Schrodinger in his judgment (but from the above it looks like a close shave)

[Quoi]

Sooooo.... If I hadnt looked at this question then it may or may not have been asked.

[Baldric]

As I understand it,
And this is only a theory,
It was the Cats responsibility to make sure the
Pencils were kept sharpened!

[Alston]

Hi Quoi.....Indeed , you may even have or have not answered the OP.

Al.☺☺☺

[jim360]

I don't know if the cat itself drove Quantum Theory forward much, although it does serve to show some of the weirdness of what is going on. That said, I'm not convinced it's as weird as all that. Basically:

1. Measuring a quantum system doesn't contain any statement of who carries out that measurement.
2. Therefore there is no reason why the cat can't measure itself.

Then it's a question of where in the great chain of who knows what you decide to sit:

-- The cat knows it is alive or dead at the end of an experiment, so it is one or the other and not both.
-- The man outside the box doesn't know, so has no choice[i but to regard the cat as being both alive and dead at the same time.
-- The man outside the room doesn't know what the man in the room observed, so has to regard the man has having both seen the cat dead and alive.
-- And so on...

I don't think this means that the cat [i]is] both, but as long as the next observer up hasn't carried out a measurement (looked at the cat, or asked the man who looked at it), then in describing the Quantum system you have to treat it as a "sum" of both options.

Looking at it this way all that is going on, really, is that "Quantum Mechanics is probability in nature".

[Old_Geezer]

I come a bit late to this thread but I think if you want to know about this the idea of "layman's terms" flies out of the window.

The issue was that according to quantum theory an unobserved sitation is neither in one state or another, but due to the weirdness of reality exists in as many states as it can at the same time until something forces reality to be one state or another.

Folk could just about get their mind around this when dealing with the very small, since common sense has been formed by our experience of the large world around us, and may not apply to quantum level things.

But Schrödinger pointed out that the quantum level stuff can affect what is going on in the world of things our size. A situation could be set up whereby radio active decay could trigger a poison release and kill a cat in the same box.

Not knowing whether radio active decay had occurred at a quantum level (something accepted as being possible it could be, yes it has decayed, and, no it hasn't decayed, at the same time) could conceivably mean we don't know whether a cat had died as a result, implying the cat is both dead and alive at the same time. Something less easy to accept.