posted 06-22-99 12:26 AM ET     

All people who read but don't write, sucks for you! But those who CAN write, but don't, post here, so we can see who is reading our posts and laughing! bwahahahaha bwahahahahaha bwahaha.... sorry...

Well, anyway, post away!

And to give you something to talk about...

posted 06-22-99 10:35 AM ET         

Periscope depth aye captain!

Up scope! (looks around)

Humm... No targets here!

posted 06-22-99 07:55 PM ET            

"The Spy Who Shagged Me" was a play on the 1977 James Bond film, "The Spy Who Loved Me" starring Roger Moore, with title song sung by Carly Simon.

posted 06-28-99 03:10 PM ET            

However, if the tree falls in the forest and nobody hears it, the sound waves still occur, and so the non-semantic answer to the question is, yes, it does make a sound in so far as the conditions occur which we define as "sound" (although it would not be *defined* as sound unless a human being were there to hear it, so it can be argued that, those conditions not being met, then no sound is *perceived*... not the same thing as no sound being *made*, however).

Err well I think so, at least!

posted 06-28-99 10:14 PM ET            

Nell... still not quite sure why she bothered with that course... hmmmm

posted 06-28-99 11:34 PM ET         

Was this trip really necessary?
I coudn't hear the tree falling because of all the power saws.

posted 06-29-99 12:06 AM ET            

Mathmatically this is shown to be wrong (on a subatomic not cat scale). The cat is neither alive nor dead. The condition of the cat is somewhere in between. Only when you look into the box will alive or dead be "chosen" and set.

A bit abstract but we have nuclear reactors thanks to theories like this.

Anyway no sound would be produced and the tree would never fall or stay standing untill someone took a look.

WK: in physics and phylosphy you must take everything as a closed system. Otherwise you have to throw in Chaos theory and dinosaurs would eat you.

posted 06-29-99 12:28 AM ET            

But then if I am there looking, it can never be empty, can it?

posted 06-29-99 12:52 AM ET         

What does that make me?

A lurker or an unlurker? Or a poster wannabe?

posted 06-29-99 02:42 PM ET            

HelloKitty, the schroedinger's cat experiment is a wonderful example of the oddness of Quantum theory, and as a thought experiment it can't be faulted. Unfortunately there's no way to actually test it out as any way of looking into the box *whatsoever* will collapse the probability field and determine the nature of the events transpired. The same goes for observing these quantum events on a subatomic scale, if you look in any fashion then the event is determined.

posted 06-30-99 03:13 PM ET            

One... Tree falling: Unless it falls in a vacuum, it makes a sound. When it strikes the ground, even in a vacuum, it will make a sound. Always. Observer not needed of any kind. That's basic newtonian physics and conversion of the potential energy through to a kinetic action (a pressure wave). You only need an observer to experience the pressure wave and judge its musical qualities (Noise, Quality, etc).

Two... Shrodenger's cat experiment always overlooked the BIGGEST DAMNED FLAW THERE IS! The CAT is an active observer, so there is no Quantum Possibilities in the stated conditions. [It's either dead or alive. And it knows if its alive.] Shrodenger has been laughing his ass off at all you dumb snots who have been propogating that since he first stated it.

Jimmeney Freaking Christmas and Hopping Popping Fourth of July people!

posted 06-30-99 03:21 PM ET            

I HAVE BEEN LURKING FOR THE PAST SIX MONTHS

MAYBE TWO OR THREE POSTS,

posted 07-02-99 08:47 AM ET            

It doesn't matter that the cat is an active observer because it has no way it can communicate it's state to the outside observer It doesn't matter whether the cat knows it is alive or not, that has no bearing on the observer outside the box. From that frame of reference the cat could be alive or dead. Then again who cares? It's only a cat.

A physics joke:

posted 07-02-99 09:33 AM ET            

No but the point is the same: the condition of the cat is a fact, and the definition of said fact by a human observer is irrelevant... the cat IS either dead or alive, regardless of whether a human being defines it as such. Semantics again... because we understand the conditions "dead" and "alive", we are able to describe them. However, if the conditions "dead" and "alive" did not exist, no amount of our defining them would make them exist, and no amount of our *not* defining them stops them from existing.

The Universe existed before Man existed... even though nobody was there to define it... or else nobody could ever have *become* there in the first place.

Errr... this isn't helping much, is it?

Nell... bamboozled

PS: Old_W: Sure, animals count as observers... oh and so do listening devices... but none of them matters so far as the occurrence of the event goes... I think?

posted 07-02-99 10:04 AM ET            

The whole point of the Schroedinger thought experiment is that nothing is a fact if you have no perception of it and if you do percieve it you alter it, it limits what you can see in the universe and ultimately leads to the possibility of free will. Bold statement, I'd better back it up.

If the universe is deterministic the cat would either be alive or dead, you would be able to write a complex equation given the starting points and momentum of every object in the system. This follows because we have somehow eliminated the uncertainty principle for the cat, so it should follow for all things in the universe. The universe is deterministic so we can theoretically write equations to describe every type of behaviour of everything as it interacts with everything else.

My logic is reversed there, I'll try again.

What happens if the universe is deterministic? (which in this thought experiment is the state when the cat is either alive or dead and both the cat and the outside observer know it without the outside observer observing the cat)

Firstly, there is no uncertainty in what will happen, the observer can write an equation to show what happened and predict it'll do the same thing again. He is in a deterministic universe so he must be right there is no uncertainty in the state of the cat. The outside observer does more experiments and eventually discovers the relationship between every different item in the universe. Now if he can find the initial state of these objects he can predict exactly what will happen to them, in effect he can predict the future. Human thought can be described as the interactions of particles in response to stimuli and so that too could be predicted. Therefore no free will, everything we do is predetermined. If he can find the initial condition for everything which he could if there was no uncertainty.

Now bring in the uncertainty principle, we don't know whether the cat is dead or not, there is no general rule for everything so there can be random chance, our actions aren't neccesarily the predetermined reactions of particles to each other. Maybe we can think maybe we are concious and don't just have the illusion of conciousness.

posted 07-02-99 03:59 PM ET         

Can' claim it's mine, credit goes to one
Randy F. of Chicago

posted 07-02-99 11:54 PM ET            

The tree does not actually fall. If we consider gravity to be a force, which it of course is, then the tree doesn't fall, it is pulled. Therefore noone hears it fall, but you can definitely hear it scream as it hits the ground.

posted 07-09-99 03:30 PM ET         

A cat is placed in a box together with a device consisting of a radiactive atom with a half-life of 10 minutes, a geiger counter sensitive enough to pick up the decay of the atom, and a vial of poison gas which is hooked to the geiger counter in such a way that when the geiger counter clicks upon detecting the atom's decay, the gas is released. If we peer into the box after 10 minutes, is the cat alive or dead?

Thus the conundrum is reduced to that of whether the gieger counter clicked or not, making it essentially equivalent to the falling tree conundrum. And of course the geiger counter only clicks if a radiactive decay event occurs; we know that the odds are 50/50 that such an event occurs.

This is not really a quantum problem. The quantum analog would be determining the spin state of an electron; before measuring, the spin state is indeterminate -- could be up or down, with equal probability. After measuring, the spin state is known, and subsequent measurements will yield the same result.

In both cases one can posit a mathematical formalism in which the actual state of the system is a superposition of the two equally likely states, an imaginary "probability wave" that is "forced" to collapse into one or the other state upon measuring.

In effect, the result is unknown until discovered. That is all. Universe does not choose which face to show until it is looked at. One could relate this to the law of Entropy, noting that, all things being equal, no one microstate with the same measurable properties is any better than any other, and we can't say which microstate a system is in from macroscopic observations.

Anyhow, it is only a conundrum for those who harbor preconceived notions about a system which has yet to be investigated. The rest of us just shrug our shoulders and say "What did you expect, determinism?"