Schrödinger's Cat

I'm not sure how relevant this is to this particluar topic but I want to try explain something here.

We all have a future, yes? We are all going to die. That's guaranteed. We will all live lives up until that point, doing things. This is inevitable yes? Right. If these things are inevitable and will happen one day, have they already happened in one sense? For example, if I fast-forwarded somebody's life until it came to their demise, their demise is obviously already there at the end of the life that I just happened to fast forward.

I suppose you could link this with destiny or fate or something but does anybody know what I mean?

Originally posted by Buck Division

Originally posted by Taj Mikel
reply to post by argentus

 

I'd be very interested to learn about some home style experiments we can do to demonstrate quantum theory, thanks!

I will do more investigation on home quantum theory experiments. Something as pervasive as quantum physics should be demonstrable without a lot of expensive scientific apparatus (I would think.)

Here is a link, from the "Scientific American" website, that describes some home experiements that illustrate the weirdness of quantum mechanics.

www.sciam.com...

Unfortunately, some of the key info is missing from the website. But I've seen this "quantum eraser" experiment, described in the link, performed myself, and it does give you a lot of perspective to ponder.

I have also seen a number of experiments dealing with polarized lenses (like in sun glasses) that show how to "bend light", which is not possible except in the context of quantum mechanics.

reply to post by Buck Division

Okay -- here is a home experiment, and it pretty much forms the basis for mysterious "quantum erasure". I found this experiment by digging around the Scientific American website at length:

www.sciam.com...

The above link is to a slideshow -- click on "Enlarge" to be able to read each slide.

Here is the experiment:

#1. Obtain three pairs of polarized sun glasses.

#2. Place the first pair of sun glasses on a table, so you can easily see through those lenses. (Maybe you want to place this first set of sun glasses in front of a desk lamp, so you can see clearly through them.)

#3. Hold the second pair of sun glasses in your hands, and rotate them so they are perpendicular to the first set of sun glasses. Look through the lenses in your hands. See how the lenses on the table appear to turn black? That is because the light has been polarized, and blocked. (No big deal there. You may have seen that before.)

#4. Take the third pair of sun glasses, insert them between the first and second set, and rotate the lenses by 45 degrees. Wow! Somehow, when that third pair of glasses is at 45 degrees, you can AGAIN see through all three sets of lenses. How can that be? Without that third set of lenses, the light was completely blocked. But now, we can "erase" that consequence with a third set of lenses.

#

The classical quantum mechanics answer is that we are prevented from knowing the direction of polarization of light. Inserting that third set of sunglasses into the mix has forced a quantum effect. The light is essentially polarized two different and mutually exclusive ways at the same time (just like Schrödinger's Cat is both alive and dead.) This cancels out our ability to perceive polarized light.

#

The more I think about this, the more I think it is kind of bunk. Maybe there is something we don't really understand about light and polarization, and are grasping for answers through "doublethink" and Zen? That seems more likely to me.

Originally posted by Lecter

Originally posted by boredguy
its like that ol saying

if a tree falls in the forest and noone is around does it make a sound?

I never understood why this even is a question, there is air in the forest and as the tree hits an object like ground it transfers the vibration through the air therefore making a sound. So.... why is this asked?

This problem is only loosely related to the Schrödinger's Cat problem insofar as it highlights the role of observer in the physical event. The tree falls, the air vibrates but where is the sound? Surely sound is only created when the vibrations displace the auditory hair cells of a conscious creature?

In other words, the concept of sound involves the concept of perception.

Philosophical questions arise about how conscious the observer has to be. Was it only a sound if a human heard it? Doesn't a bird count? What about a worm that could only feel the vibrations? When we say a worm feels something, do we mean it is in some sense conscious of feeling? Isn't "unconscious feeling" a meaningless concept? etc.

You can try to get around this by using the classical science definition of sound as nothing more than "mechanical vibrations travelling through some medium" - as if it could exist in isolation of any means of detecting it - be it ear, microphone or whatever. Classical science isolates the physical from the subjective in this way but quantum mechanics teaches this only gets you so far.

Schrödinger's thought experiment bridged the gap between the subatomic and macroscopic, bringing the absurd paradox of quantum superpositions from the realm of the very small into the previously mundane observable world of living or dying cats. Both he and Einstein believed this showed there must be something wrong with the understanding of quantum weirdness as it was formulated at that time. However, although there are several interpretations of how superstates collapse or decohere, quantum weirdness is something scientists have had to learn to live with.

As someone mentioned earlier, Schrödinger's Cat is only a mental excercise, not a practical experiment - quite apart from the cruelty, a cat or any other living thing could not be isolated from the universe as the experiment would require. For one thing, infrared photons and gravitons would transmit information about the cat's physical state through the box.

Max Tegmark examined the experiment from the point of view of the cat.

Question - what kind of quantum superposition was the universe in (if any) before the first conscious observer evolved?


[edit on 15-6-2008 by EvilAxis]

I think people miss Schrödinger's point entirely.

His argument was extended downward from the cat against the concept of the indeterminate state. Unfortunately much evidence and argument later defended the validity of the argument while overlooking the sarcasm.

reply to post by Spiderj


If I was locked in that room with the poison/hammer thingy, I'd sure try like hell to keep that hammer from falling in the first place.

reply to post by doomsauce


doom.....you are trying to be funny, or just completely missing the point. Not sure which.....

So, I'm voting for funny......

Originally posted by UK Wizard
Wikipedia – Schrödinger’s Cat

Schrödinger's cat, often described as a paradox, is a thought experiment devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics being applied to everyday objects, by considering the example of a cat that may be either alive or dead, according to an earlier random event.

In the paradox proposed by Schrödinger a cat is placed within a box that contains a small amount of radioactive material which may or may not (50% chance of) decay within the time period of an hour. Should an atom of the radioactive material decay it will be detected by a Geiger counter and then through some means activate a hammer which smashes a vial containing cyanide presumably killing the poor cat.

Without opening the box and presuming we can't see inside the box with any other means how are we to determine whether the cat is alive or dead before the opening of the box at the allotted hour?


[edit on 12-6-2008 by UK Wizard]

You can't know if the cat is alive or dead because you can't know something until you observe it with one of your five senses. You can make an assumption, but it won't necessarily be correct.

Does that mean that nothing in the universe happens until we see, feel, hear taste or smell it happen?

What if the world around you is an elaborate dream and you're really all alone?

[edit on 15-6-2008 by zephyrs]

reply to post by zephyrs


OK....last try....it is a thought experiment. Has nothing to do with killing a cat, or any other animal, that is a metaphor, an idea used in 1935 to serve as a detector.....think of the canary in the mineshaft, for example!!!

Please, may we focus on the larger picture, here, of the weirdness of Quantum Physicis?? And a little less on a hypothetical cat????

(no cats or other animals were harmed in the production of this hypothesis. This disclaimer is not to be construed, imagined, nor implied to suggest future harming of cats or any other quadroped, nor any other animal in the future. Any claims to the contrary will be assumed to be an infringement on intellectual property rights, and will be dealt with accordingly.)

This is how I would imagine an attorney, for Herr Schrodinger, were he alive today, would have to file a disclaimer.

I return control of your computer screens to you..............

Fare thee well, Herr doctor.....fare thee well..........

The problem I've had with the experiment is that it doesn't take into account the consciousness of the cat. We don't know the outcome, but the cat does, so something conscious of its own existence knows the outcome. Maybe he should have used a donut. Does cyanide affect donuts?

As for the tree/sound thing. Do we define sound as something heard? If so, that implies something needing to observe the sound for it to be a sound. Otherwise, it creates vibration but to me, only sound if it can be percieved by a hearing creature.

I don't think the guy should be handling cats period. What about a heart rate monitor? $12.99 I think he needs to give up his lab station too.

Just kidding.

Once you observe the cat and know that its dead that means the whole time you were thinking about whether the cat was dead or alive or in two states at the same time it was actually all along dead. This means that when you observe something it doesn't change the outcome you just finding out whats already there

I like the donut concept. It could have a cup of coffee and a dunker.

Did the donut get dunked in the coffee?
This raises a very important philosophical question.

If a donut gets dunked in a cup of coffee, and there is no one there to eat it, who picks up the tab?

Originally posted by Cyberbian
I like the donut concept. It could have a cup of coffee and a dunker.

Did the donut get dunked in the coffee?
This raises a very important philosophical question.

If a donut gets dunked in a cup of coffee, and there is no one there to eat it, who picks up the tab?

If there is nobody there to eat it then there is nobody there to give the money TO either....

reply to post by UncleV


UncleV....

You have a subtle sense of humour, thanks for making me laugh so much just now!

My comedy stylings (poor attempt, anyway) are more of the slapstick variety. Yours were sublime!

BUT, however....the consciousness idea has some good merit for contemplation, IMO. Could the 'cat' be aware of his peril? If knowing that there was danger, could the cat use one of his other lives to escape? Or, just pass on the experience via his consciousness to other cats, in a parallel reality, to warn them?? Many philosophical questions remain.....

reply to post by zephyrs



What it means is "nothing in YOUR universe happens until YOU see, feel, hear taste or smell it happen" It's your perception of reality , reality is individual. Prior to me typing this I did not exist in your reality , does that mean I wasn't here? Potentially as I sit and type this I could have green hair (although it's highly unlikely), you have no Idea until you OBSERVE me. Do you know where I am?.... It's possible that I'm next door to you. So in your reality or perception I could be anywhere. You don't know. Does your not knowing where I am change the fact that I am In New Jersey Right Now? No... I'm getting repetative here... this is something else that's fun to wrap your head around... The Heisenberg Uncertainty Principle

And now we come to the realisation of the possibility that everything that happens in one's life,happens in a way that one has been conditioned to perceive it.

Do we die because this is what we believe will happen eventually,because this is what we have been conditioned to believe?

Do we get old for the same reason?

How could someone shake off the conditioning to the point of proving to one's self that conditioning and beliefs are all that make one's perception of reality manifest?.

Do we really have to accept the accepted reality,the accepted way?.

Hmm?.

*Head explodes*

Very interesting experiment! Can't wait till I look into the pro-found scientists in the wiki link Calculus based physics here I come!!!

I suppose the best approach to this is simply step back..and take a breather....




Best Regards,

Richie

We are all part of the whole,we have been conditioned to believe we are all separate from one another,we are conditioned to think this way so we feel the need to fill the empty space where one-ness once was with stuff.

You are conditioned to think like you do so that you are open to being sold # you don't need,to fill up your empty cupboards.

Your cupboards are well stocked,you just don't realise it.

This is all only temporarily permanent.

Or permanently temporary?.

Nothing is everything.

reply to post by PokeyJoe


I am sorry. But I cant help but be at once amused and dismayed at the way some of us think. The scientific method is one in which we produce repeated phenomena and come to conclusions based on observation. Deductive reasoning leads us to believe that the sun will rise again tomorrow. That when something moves, it creates a vibration, which when met with an ear, is interpreted as sound. (If there is no ear, no sound, due to sound being the result of vibratory waves moving against resistance). Until an interior or exterior force is exerted, a creature will remain alive or dead. I understand the metaphor of a cat in a box and a tree in a forest, and it, like all analogies, breaks down eventually. But what really gets me is when intelligent people actually argue about things that are so obvious. YES a tree will make "sound waves". Observation by human senses is not a prerequisite for the occurrence of phenomena. One may argue that it was my observation that brought me to that conclusion so therefore my reasoning is suspect, but then I would say that that person is guilty of observing my observation and therefore has no valid argument, but then he could say....

See how ridiculous it gets? It is possible that ones mind can be so open to every possibility that it actually falls out.