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Nostradamus
10-14-2007, 4:52 PM
I was looking back at my very small collection of newscientist magazines late last night when I stumbled upon the article of multiverses and parallel universes. In the article there was an explanation of the theory of Schrödinger’s cat, which proved to keep me up all night thinking about it.

It claims that there is a cat in the box. In our universe it would appear that there are two outcomes, only one of which will come to be, either you open the box and the cat is alive, or you open the box and the cat is dead. This theory therefore means that if you flip a coin two universes are created, in one the coin lands on heads and in the other tails.

However if this theory is right, by my thought every single second each person must create hundreds of thousands of universes. For example, there are twelve books on my shelf and I am going to pick one, by my thought this would result in twelve universes being created, one for each choice of book. However, surely other variables would affect the universe, take my arm extension for example.

So by my thinking there would be an almost infinite amount of universes created simply by choosing a book:
Book 1 + Length of arm extension 1
Book 1 + Length of arm extension 2
Book 1 + Length of arm extension 3...
Book 2 + Length of arm extension 1
Book 2 + Length of arm extension 2...

And then other variables such as my breathing, other movement, the movement of each individual muscle in my body, the diffusion of particles in the cells in my body, eye movement, all would affect the universe.

Or this is at least my interpretation. Have I got this theory wrong?

And if this theory is right then are these parallel universes all held in the same existence i.e. can someone from one of these universes theoretically travel to another, perhaps through a black hole?





And I know this is off the topic but I find this interesting as well. If this theory is right should we let it affect how we live our lives? For instance of you nearly miss a car in one universe you die, should we feel guilty because of this?

Anoiktos
10-14-2007, 4:56 PM
For instance of you nearly miss a car in one universe you die, should we feel guilty because of this?
If you take the multi-universe theory seriously, you really shouldn't, because there are a huge number of universes in which you die at that exact same moment for unrelated reasons, say a heart attack or a sudden desire not to breathe.

Icarus
10-14-2007, 7:43 PM
Excuse me i may have just missed your entire point but how are they proposing universes are formed?

The whole schrodinger's cat -> parrallel universes seems to be lacking any connection as well

Darmago
10-14-2007, 9:53 PM
Assuming the multi-verse theory I heard is correct, that there are an infinite amount of universes, the two universes "created" by the schroedinger's cat situation would actually have been there since the beginning of time... however they were completely indistinguishable from each other until one cat died. Since there are an infinite amount of different universes, this is true.

Ktan
10-15-2007, 1:32 PM
Schrodingers Cat is more realted to something else. Yes, it can be applied here, but IIRC, It relates more to the cat being 'alive' and 'dead' at the same time, because, according to nuclear decay, the cat could be either of those outcomes, but because it is a closed system, we cannot tell which it is.

At least, I seem to remember that from somewhere, but I can't be sure.

Darmago is indeed correct, if there are multiple different universes, they have most likely been there since the 'start'. Also, to feel guilty about your effects on another universe is quite uncomprimising, because, since it is parallel, nothing you do can affect it.

Due to infinity being such an odd concept, if you divide it by any number you get infinity anyway, so you're only 'saving' one in infinity yourselves while the other infinity are dying.

eg

there are two possible outcomes, you live or you die.
So, Infinity /2

= Infinity.

So, it's rather a minor shift in everything.

My belief (since we can in no way prove it) is that it is not the movements that dictate the new universe, more each universe contains each different combination that are possible.

This is, of course, based on the assumption that the Multi-Universe theory exists, and also conforms to this pattern of belief in it.

Darmago
10-15-2007, 2:15 PM
Hmm

Something I didn't think about

But the two different universes in which the outcomes for the situation are different, would have been different from the very beginning of the universe... possibly by an infinitesimally small shift in some constant or another.

UnHoly-Assassin
10-15-2007, 3:46 PM
In an open multiverse, there would be an identical you about every 10^10^29 meters, for an infinite amount of meters. So, you are actually living in infinite amounts of universes right now. Mind boggling, isn't it?

Lazere
10-16-2007, 1:39 PM
But the two different universes in which the outcomes for the situation are different, would have been different from the very beginning of the universe... possibly by an infinitesimally small shift in some constant or another.


Well, not necessarily. If there is an infinite number of universes, then there would also be an infinite number of universes that are identical, until they hit a certain point. Also, there would be an infinite number of different universes, even if those differences were unnoticeable.

For example, this universe was identical to an infinite number of universes until the very moment I decided to write this, then it split and now they are no longer identical. There is still an infinite amount of universes that are identical to this one, but now there is also an infinite amount of universes in which I didn't write this. (To simplify it)

Anoiktos
10-16-2007, 1:45 PM
For example, this universe was identical to an infinite number of universes until the very moment I decided to write this, then it split and now they are no longer identical. There is still an infinite amount of universes that are identical to this one, but now there is also an infinite amount of universes in which I didn't write this. (To simplify it)
WHAT YOU SAY!?

I believe the short way of saying that is thus:
At any point, there are an infinite number of universes in which any possible action has been taken.

If you do some study into the way light functions, this becomes increasingly probable. (Short version: Light follows the fastest path from one point to another, regardless of the nature of the obstacles in its way, in such a way that it is likely going in every direction at once, but merely 'collapsing the wave-form' (as schrodinger's cat) whenever a wave/particle first hits an observer.)

Nostradamus
10-16-2007, 3:36 PM
So every single infinith (sp? 1/infinity) there is an infinite amount of universes being created according to this theory?

So are these universes all being 'kept' in the same existence or are they entirely separate. i.e. Imagine there is a giant chest of draws that is existence in its entirety. Is our universe just one of these drawers, or are all these universes being kept in the same drawer?

Anoiktos
10-16-2007, 3:39 PM
So are these universes all being 'kept' in the same existence or are they entirely separate. i.e. Imagine there is a giant chest of draws that is existence in its entirety. Is our universe just one of these drawers, or are all these universes being kept in the same drawer?
Regrettably, most people find it difficult to build a castle on a cloud. That is to say, you're asking for specifics to a theory that doesn't have enough material proof to theorize that kind of specific. That said, all of the artists' interpretations of this sort of thing I've seen have been like a huge three-dimensional dot-grid of bubbles, each representing a single universe.

Lazere
10-16-2007, 7:47 PM
So are these universes all being 'kept' in the same existence or are they entirely separate. i.e. Imagine there is a giant chest of draws that is existence in its entirety. Is our universe just one of these drawers, or are all these universes being kept in the same drawer?

The main problem with this is that these universes are infinite, they can't be kept together. It seems (to me if not to anyone else) that each universe is a separate entity, not like separate drawers, but more like the universes in different video games. These video games will never cross, and what you do in one video game will in no way affect the other. What happens in one universe will happen the same way no matter what happens in this one...

DoctorZettabyte
10-16-2007, 9:57 PM
Slightly unrelated, but what are all these Universes contained in? We can't all exist in a great big nothing, it would have to be constantly expanding, otherwise it is possible to run out of space to put stars, galaxies, what have you.

Back on topic, this thread is rather binary with its theory. I'm not sure if this has been discussed before, but it all has to do with your thought about the outcomes, and the choices made to get there. For instance, many of you are saying that every one of your molecules in your sack o' wattah (body, for you terminology freaks) has a separate universe for each possible action. (Math sidenote, just thought of this...the number of universes would grow exponentially for each moment another is created and an event happens) But what if you cease to choose what happens to you, if that were possible? I know I'm stretching it here, but what if this whole thing depended on choice? You could choose to stop breathing, eating ,walking, running, caring, blah blah. No universe was created, because there is no outcome or change! The last universe to be created by you would be the one where you stop choosing.

Travel theory time, kids! If these universes are being created for every moment, yadda yadda, then everything could naturally move between universes unless they moved instantly to a universe- free area (see Where to put it all, above) Sideffects may include earthen destruction, universal error, BSoD, color inversion, and bloating/indigestion.

Thanks for reading, and don't blame me for mindless babble, I haven't posted here for a while, and organization has always been a fuzzy concept to me.

//Xerabyte

Lazere
10-17-2007, 11:11 AM
I know I'm stretching it here, but what if this whole thing depended on choice? You could choose to stop breathing, eating ,walking, running, caring, blah blah. No universe was created, because there is no outcome or change! The last universe to be created by you would be the one where you stop choosing.

Travel theory time, kids! If these universes are being created for every moment, yadda yadda, then everything could naturally move between universes unless they moved instantly to a universe- free area (see Where to put it all, above) Sideffects may include earthen destruction, universal error, BSoD, color inversion, and bloating/indigestion.

First, the choice thing... Supposedly, if it all depends on choice, then the second you chose not to chose anymore it stops? I would like to point out the first chose there. You have to chose to stop making choices, therefore creating another universe where you didn't chose to stop making choices. That universe would then continue the path just as every other universe there. It's not like this one would be some special "key" universe that is the only one that can make other universes... If the multiple universes theory is true, then odds are that we are just a copy of another universe...

Second, when you get this deep into the quantum physics realm, it gets a bit difficult to understand, there is no need for a place to "put it all", these are infinite amount of universes. They don't have to be just side by side, they could be on different planes of existance altogether, thereby eliminating the need for a "place to put them".

DoctorZettabyte
10-17-2007, 10:31 PM
This doesn't answer the "where to put it all" point. Where does it all go? If we were to put each universe on a different plane of existence, none of our current metaphysical laws should apply, and yet they still do in this current "multiverse".
I personally think this different-universe-for-everything-that-happens thing is a load of dung. Sure, there are probably other universii out there, but one for every moment something happens? We would exist in over one gogol places at once! We would be thinking millions of thoughts, have just as many emotions, and all within the blink of an eye? Preposterous.
Back to the expansion into who-knows-what: How do we even know that the universe isn't collapsing in on itself as we post here? What is space expanding into, if it is expanding at all? The big band was supposedly the frame of our current universe, compacted into a tiny dot that could fit on the head of a pin. Where did that come from? What is it moving into? Surely it must exist in something...you can't just fling yourself to the big dark one and pray for the best, or that you'll hit a magic brick wall...you'll eventually hit a point where you will run out of places to fly.

Deep points of thought indeed.

//Xerabyte

Ktan
10-18-2007, 10:55 AM
This doesn't answer the "where to put it all" point. Where does it all go? If we were to put each universe on a different plane of existence, none of our current metaphysical laws should apply, and yet they still do in this current "multiverse".
I personally think this different-universe-for-everything-that-happens thing is a load of dung. Sure, there are probably other universii out there, but one for every moment something happens? We would exist in over one gogol places at once! We would be thinking millions of thoughts, have just as many emotions, and all within the blink of an eye? Preposterous.

Genetically, if the human race continues for long enough, there will be a repeat of the three trillion (I think) possible combinations somewhere. The idea of two people exactly the same DNA but completely different personalities isn't preposterous, if anything, it's scientifically possible, even without twins.

No offence intended, but there's nothing that would make you any more special than anyone else in the uni/multiverse. Just because someone 'exists' in one place does not mean you can't have a copy elsewhere. There is not a DoctorZettabyte quota. To deny this fact would be to imply that we all have some kind of special rule which makes us impossible to emulate, which is just false reasoning.

To further emphasise the point, you aren't thinking these one hundred million (though actually infinity) thoughts and you aren't responsible for them any more than you would be responsible for someone who shared your exact same genetic makeup. As far as I know, there isn't a 'there can be only one of each person' rule, not even within a universe, never mind a multiverse.


Back to the expansion into who-knows-what: How do we even know that the universe isn't collapsing in on itself as we post here? What is space expanding into, if it is expanding at all? The big band was supposedly the frame of our current universe, compacted into a tiny dot that could fit on the head of a pin. Where did that come from? What is it moving into? Surely it must exist in something...you can't just fling yourself to the big dark one and pray for the best, or that you'll hit a magic brick wall...you'll eventually hit a point where you will run out of places to fly.

Deep points of thought indeed.

//Xerabyte

Actually, there's a recently proposed theory that essentially explains the expansion without the big bang. I read it in New Scientist. Essentially, our universe is a 'ball' in what is essentially for the sake of simplicity a naval mine shaped ten dimensional object. As it descends into one of the prongs, it contracts, whereas if it were to 'spin' into the main body of the 'mine' the Universe has room to expand.

Otherwise, there are theories such about Dark Energy. Take an elastic band and stick four lolly sticks along it, parallel along the length of the band. If you stretch the band, there is a greater increase at the furthest end, I believe it's in an exponential fashion. If Dark Energy worked like this elastic, that would explain why the universe is able to expand faster than the speed of light. Indeed, the ten dimensional mine model could also account for this phenomenon.

To 'reach' the end of the Universe would require you to travel faster than the speed of light, even if it expanded at only the rate of the speed of light. This is physically impossible, as far as we can suppose, so you wouldn't be able to reach the end of the universe.

The Universe is such a baffling concept on its own that simply expecting there to be space to expand into is expecting something that's far too simple for us to understand, surely? Of course, the mine model could account for this (then posing the question, what is the mine in?)

It's all a very difficult subject, because, frankly, we're hardly qualified enough as it is, never mind post phd Physicists getting a headache from this kind of stuff :P

However, fortunately it's a topic that allow people to explore their beliefs and opinions on the subject too, so you don't actually need a phd to discuss it (but I'm sure that one helps)

Hasharin
10-18-2007, 8:19 PM
dude, ur completely effing incorrect. There are not thousands of universes. there are KAZILLTRILLBILLMILLION universes. (sorry fro the random number:P)

I was thinking about everytime someone dies, the world splits in two; one in which the person dies and one in which they narrowly divert death. also, i don't thinl that it happens with "major events" because what would define something as major? While many people can agree on that, there is no way of defining a "major" event.

CrazyTom
10-18-2007, 8:38 PM
Putting a cat in a box in the name of science? Sick bastards.

The cat is alive.

Furthermore, a black hole is simply (well, I say 'simply') an area where huge amounts of matter have been compressed to a tiny, immensely heavy point, isn't it? There's no reason to assume such an object would allow you to travel to another multiiverse.

Hasharin
10-18-2007, 8:53 PM
well, saying that the black hole is "heavy" as you stated, would mean that the universe would be like a fabric with small impressions made on it by bodies such as pulsars and stars. A black hole, which is really the mass of a flippin' big star inside a singularity, would be so heavy that it would rip through this fabric to another fabric (a hole in the drawer :P)

CrazyTom
10-18-2007, 9:21 PM
Not if the fabric is especially rubbery... wait, what the hell am I talking about? It's ridiculously unquantifiable... last time I checked, black holes were still only theoretical.

Also, it depends on the way you assume gravity works (we don't know yet, all we know is it does). For all we know, every object sends out little graviton particles which draw things toward it - the bigger it is, the more gravitons it can generate. For various reasons, I'm currently a fan of Intelligent Falling. :D

Incidentally, multiple-universe theories are one possible explanation for why gravity is so ridiculously weak compared to other forces - its particles or waves move 'sideways' through different dimensions, thus spreading its strength throughout several universes.

Hasharin
10-18-2007, 9:33 PM
Agreed. Everything is theoretical...T.T

ecyor0
10-18-2007, 11:40 PM
(reads thread)

And they accuse Christians of making illogical fabrications......


Anyway, I seem to have misinterpreted the whole Schrodinger's cat idea. I thought the idea behind it was that as long as the cat is in the closed box, you couldn't know for certain that it had in fact died. And so the question arises: "When you open the box to find the dead cat, was it dead before that, or was it the act of observing that made the cat dead?"

Anyone able to confirm/refute that? Kinda confused.....

CrazyTom
10-19-2007, 9:42 AM
You can hear the damn thing meowing inside the box.

Ktan
10-19-2007, 9:50 AM
dude, ur completely effing incorrect. There are not thousands of universes. there are KAZILLTRILLBILLMILLION universes. (sorry fro the random number:P)

Actually, you're wrong, if I was wrong by that same token. I was just saying a hundred thousand for the sake of example, but if you're going to come here making weaksauce attacks like that, I'll simply say that instead of making up a random number, why don't you actually say infinity, which is correct? That, and if you think that undermines my entire argument, then you truly are sheltered. Put more effort into your IR posts. The difference between my 'wrong' was that it wasn't the sole content of my post, thus I was not 'completely effing wrong', just a small part of it was.

Otherwise in the post you made, what you supposed didn't really fit in because that's stuff we've already discussed here. It was clear that you hadn't read anything in the thread before it from your post, which is tantamount to jumping of the IR cliff.

In fact, the past few posts have been somewhat dubious in this thread. C'mon guys.

Btw, Crazy Tom, the cat is assumed to be impossible to hear. Also, it's a hypothetical idea, it's not something that has, as far as I know, actually been proven.

Yes, Black Holes are theoretical, but by the same token that gravity is theoretical. You can't see it, but you can be about 99% certain it exists from all the effects it causes. There are a number of things in the universe that could only be accounted for by a Black Hole.

I don't know if anyone else had ever thought of it, but I did imagine that perhaps 'whit holes' (the oppsoite of a black hole, something which is even more theoretical) is actually the 'impression' from another universes black hole. Eg, you take a ball and shove it into a thin layer of playdo, you will get a ridge on the other side. Ither theories are that the White Hole is the 'exhaust port' of another black hole.

There's also the worm hole theory of if you pass through the outer event horizon of a rotating black hole, you could ptoentially come out of another black hole. Rotating black holes have tow even horizons, so you could potentially time it to get in between the two, but we have no idea what this would do.

http://upload.wikimedia.org/wikipedia/commons/thumb/a/af/Worm3.jpg/350px-Worm3.jpg

I suppose here, it could be a meeting of a black hole and a white hole in the centre, or maybe even two black holes (or possibly it is even the case that each exit is one of the rotating event horizons, in which case this diagram would sort of fold in on itself, or be two linked black holes)

But, essentially, Schrödinger's Cat has been taken as part of a totally different theory, leading to a very messed up topic. To be honest, I've considered changing the title because we aren't discussing Schrödinger's cat at all.

http://en.wikipedia.org/wiki/Schrodinger%27s_cat

From what I've read, to open the box to 'find out' is to alter the experiment, so the result is that the cat is both alive and dead at the same time, it being a paradox. This has nothing to do with the multiverse theory, or at least it would hve a very dubious connection, no more than picking your nose can be related to this theory.

Lazere
10-19-2007, 11:49 AM
The only real connection Schrödinger's Cat has to the multiverse theory is that it is a parallel theory of sorts. It is on the same token as the multiverse theory in that it attempts to explain why scientists keep getting different results for the same experiment on the quantum level. Basically, it says that all particles exist in all forms until observed where they then assume a certain form, hence, the cat is both alive and dead until you open the box and find it either dead or alive...

CrazyTom
10-20-2007, 5:54 AM
K'tan - yeah, I was just being faecetious. :)

Ktan
10-20-2007, 8:48 AM
Ok, but just bear in mind, this is the IR, so people are very much against things like that.

Basically, being facetious can lead to GA coming down on your like a ton of bricks. I mean, absolutely no issue outside the IR, but in the IR it's in many ways an infractionable offence.

Oblongato
10-20-2007, 4:18 PM
The only real connection Schrödinger's Cat has to the multiverse theory is that it is a parallel theory of sorts. It is on the same token as the multiverse theory in that it attempts to explain why scientists keep getting different results for the same experiment on the quantum level. Basically, it says that all particles exist in all forms until observed where they then assume a certain form, hence, the cat is both alive and dead until you open the box and find it either dead or alive...

I'm not well versed on The Cat, but I find the theory that particles can exist in all forms simultaneously to be a bit far-fetched. If my layman's understanding of quantum mechanics is making me look stupid here, please feel free to step in, but it sounds very much like we want to come up with an answer although we lack the capability to look deeper to find the cause of this apparently random behavior. Is there anything that links this theory to real science, or is is purely metaphysical?

Lazere
10-20-2007, 8:46 PM
Oh, it's pretty much metaphysical... You could probably find some stuff on it, but I doubt that it would help you understand it any better. Honestly, I doubt that the people that subscribe to these theories understand them that well either. The Cat says that all quantum particles are in all states at once until they are observed, making humans a key ingredient, and somehow different, than the rest of the universe. This is where I begin thinking it's a load of crap, but I'm not exactly a quantum physicist, so who am I to say?

Graeme
10-20-2007, 8:59 PM
The Cat says that all quantum particles are in all states at once until they are observed, making humans a key ingredient, and somehow different, than the rest of the universe. This is where I begin thinking it's a load of crap, but I'm not exactly a quantum physicist, so who am I to say?

You're reading into it too much.

The cat is a very simple model for the quantum mechanical oddities and curiosities that were being witnessed at the time. As you stated, the mind experiment states that in a closed system, an object (ie. a particle) may occupy state A, state B and both state A and B at the same time. This is the basis behind quantum computing and is, in fact, a very real and very observable effect.

The whole observation thing comes into play because in order to observe something, you must disturb it from its original state - you force it to a given state (re: A or B). The same would apply if, say, a dog decided to measure the spin of an electron in an otherwise closed system. By taking the measurement, it alters the system and forces the electron into either spin up or spin down - not both. Of course, the dog doesn't have the intelligence or knowhow to analyze the results of the experiment, or even know what the spin of an electron is in the first place :).

GenocideAlive
10-20-2007, 10:10 PM
Just a quick refresher on the IR rules. No one-liners, no dumbass quipping for your entertainment. No tandem posting without addressment of the topic. I've seen it plenty, and that's plenty enough. Cut it out.

Lazere
10-21-2007, 12:14 PM
Ok. But then one question remains. How, or why, does measuring something make it assume a certain state. This would imply a concisenesses among quantum particles to be able to assume one state or another while being measured but more than one state while not being measured.

Oblongato
10-21-2007, 1:09 PM
I think I can grasp the concept that the state of the thing we want to measure cannot be measured without knocking it into another state. But it seems to my (layman's) understanding that it would be more logical to say that the unmeasured state is not A and B, but rather neither A nor B. Could someone clarify?

Lazere
10-22-2007, 1:21 AM
That would be a more logical approach, but that isn't what the theory is... I have no idea why someone would decide that they are in all states at once, and then assume one or another when being observed.

GrassDragon
10-22-2007, 1:24 PM
I think all of you should try to educate yourselves a little more about quantum theory before jumping in here. Quantum physics is a science that is still being developed, but a lot of conclusions drawn through quantum theory are true and experimentally reproducible, strange as they may be. The world on a quantum level is far different than our common, macroscopic world, which is what trips up a lot of people when they think about quantum theory. The best advice I can give is to throw out pretty much everything of what you've learned about physics when you try to think about things on such a microscopic scale.

First, most of the affects we're talking about only pertain to quantum objects, objects that are extremely small like electrons or photons. Something like a computer can never be in two states at once, like on and off, because of a process called decoherence (this is an extremely confusing topic and one that many physicists don't understand; I suggest to try to do some research about the basics of decoherence on your own.)

However, this superposition of states is observed with quantum objects. Electrons, before they are observed, are both spin up and spin down at the same time. If you measure the spin of an electron one moment, and then again the next moment, it can have different spins due to quantum interactions. An unobserved electron is in a superposition of both spin up and spin down states, which basically means it has a probability of being up or down when you measure it.

Particles are said to be in both states because they actually are. The probability of each specific result happening can be represented mathematically and graphed as a wave function. This wave function is the sum of all possible outcomes for the particle. When an observation is made, the wave function collapses so that a single outcome has a probability of one, and all others have a probability of zero; this means that only one result occurs, which is what we observe. To say that a particle is in none of the possible states before we observe it is not only wrong, but also implies that an observation creates the state, which is not entirely true.

The Schrodinger thought experiment has more to do with the differentiation between "macroscopic" and "microscopic" objects. I said a computer can't be in a superposition but an electron can. This is obvious because they are at the extremes, but what about a molecule or a single celled organism? Where is the division between the world that quantum theory governs and the world that newtonian physics governs? Can something as big as a cat really be both alive and dead?

It is also used to discuss what constitutes an observation. In the original experiment, an atom of a material with a known half life is put inside a geiger counter. When some kind of radiation is detected, the geiger counter sets off a device that breaks a vial of poison that will kill the cat. At a time after the half life, the atom should be in a superposition of being both decayed and not decayed, since there is a 50% chance of either happening; this result has been verifying experimentally and is definitely true. When the atom is observed it should collapse into one of these states. But do you actually have to open the box and look inside to make the wave function of the atom collapse? If a geiger counter is detecting radiation, is this enough to make it collapse? If a cat would be dead or alive, depending on the state, could that be called an observation?

Schrodinger's Cat is not a theory in itself, it's a gedanken experiment that physicists can use to explore the quantum world, and try to discuss its mysteries. While I can see some connection with Everett's Many Worlds Theory, that's not it's many purpose, and the alternate universe theory is another ball of wax that really cannot be verified or proven with current technology.

Quantum theory, on the other hand, definitely can be proven, and has been proven in the past. If you are interested in it, I would suggest reading up on the GHZ experiment, which first proved that quantum objects actually are in a superposition instead of a state that we just don't know before we observe. For something a little more basic (because the GHZ experiment is kind of advanced and confusing), you might try the double slit experiment and some of its variations, like the quantum eraser and delayed choice experiments. I'll warn you that the results of these experiments are really weird, but they are true. Be prepared to forget about how reality works when you step into the quantum world.

Oblongato
10-22-2007, 2:07 PM
I'm sure it's no one's intention to annoy you with ignorance of the topic, but please realize also that this is not a physics forum populated solely by people who study (quantum) physics. I had hoped just to pick us a little more knowledge about a particular question in the field. Instead of blindly starting out somewhere to study the whole field in the hopes of finding my answer, I asked a targeted question in the hope that someone could at least provide some direction.

As it happens, yours was exactly the sort of answer I was looking for, and thanks for that.

Nevertheless, before I start researching decoherence, perhaps you could answer another question.

If we cannot predict the spin up / spin down states (and get a 50:50 result), why would we assume that the electron simultaneously occupies both states instead of assuming a rapid and unpredictable changing of states? What is the origin of the theory that an electron can occupy two states simultaneously?

GrassDragon
10-22-2007, 3:00 PM
I did not intend to come off as condescending; I just hoped to provide some background and basics regarding quantum theory.

...why would we assume that the electron simultaneously occupies both states instead of assuming a rapid and unpredictable changing of states?
If you look into the double slit experiment (which I would strongly suggest you do, before decoherence), you will find that the results are only possible if particles can be in more than one state at a time.