Schrodinger Cat Disproof (Samuel Jacobs)

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Schrodinger Cat Disproof (Samuel Jacobs)

Postby SammySpicer » Sun Sep 07, 2014 10:23 am UTC

Proof that the Schrödinger's cat experiment cannot exist via contradiction.

Let there be a sample space which encompasses every object.
Let the sample space be divided into two sets which do not intersect each other and are called dead and alive.
A cat is placed into the box with the cyanide capsule which can go off any minute.
Schrodingers principle states that the cat cannot be either alive or dead until the box is opened and it is observed.
This means that the cat doesn't exist within the set dead, or the set alive, and so doesn't exist inside the sample space which encompasses every object. Which means that the cat doesn't exist.

But this is absurd, as the cat was put in the box before,
Ergo, schrodingers theory is disproved.

Q.E.D

Samuel Jacobs.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby gmalivuk » Sun Sep 07, 2014 1:35 pm UTC

All you've shown is that there is at least one false premise. You want it to be the premise that the thought experiment is valid, but it could just as easily be your premise that 'dead' and 'alive' are disjoint and between them include everything.

I'd argue that that's a false premise even from a purely biological perspective, without ever having to bring quantum weirdness into it at all.

Another way to see how your argument is flawed is to note that it would disprove other quantum effects that have actually been observed, such as the double slit experiment (the sets are photons that go through the right slit and photons that go through the left) and entanglement (the sets are spin up and spin down particles, for example).

If your argument appears to disprove the most successfully and precisely confirmed scientific theory ever devised, your argument is probably wrong.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Sun Sep 07, 2014 1:55 pm UTC

SammySpicer wrote:Let the sample space be divided into two sets which do not intersect each other and are called dead and alive.

http://en.wikipedia.org/wiki/Begging_the_question
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby ahammel » Sun Sep 07, 2014 2:18 pm UTC

gmalivuk wrote:If your argument appears to disprove the most successfully and precisely confirmed scientific theory ever devised, your argument is probably wrong.

Wouldn't the argument just disprove the Copenhagen interpretation?

Follow up question: wasn't the Cat intended to show that there's something weird with the Copenhagen interpretation anyway?
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Sun Sep 07, 2014 3:32 pm UTC

No, it was intended to show that you shouldn't take quantum mechanics too seriously. Which is wrong, you should, but decoherence happens in between the scale of atoms and cats. Schrodinger was not actually very good at quantum mechanics.

Regardless of interpretation, "alive" and "dead" are a basis for the sample space, they are not the entire sample space.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby douglasm » Sun Sep 07, 2014 7:32 pm UTC

As I understand it, in order for Schrodinger's Cat to be valid if actually carried out, the box would have to be so thoroughly isolated that not even so much as the state of a single photon outside the box could be affected by the cat's life or death before opening the box. Setting this up would be difficult.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby thoughtfully » Mon Sep 08, 2014 12:05 am UTC

douglasm wrote:As I understand it, in order for Schrodinger's Cat to be valid if actually carried out, the box would have to be so thoroughly isolated that not even so much as the state of a single photon outside the box could be affected by the cat's life or death before opening the box. Setting this up would be difficult.

I'm pretty sure you also have to cool the cat down to a pretty ridiculous fraction of a degree above absolute zero, to keep the poor cat from decohering itself. Which pretty much renders the whole exercise moot.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Meteoric » Mon Sep 08, 2014 12:07 am UTC

"The cat is simultaneously alive and dead" also seems like the kind of trouble you can get into when you carelessly translate physics into everyday terms. "There are temporarily two cats, one alive and one dead" might not be a terrible alternate translation, and completely sidesteps the "disproof" here. If your contradiction hinges on which words you choose to qualitatively describe the math, it's not a very good disproof.

Basically, if you're "disproving" QM phenomena without looking at any actual QM, probably you're wasting your time.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Mon Sep 08, 2014 3:21 am UTC

Meteoric wrote:"The cat is simultaneously alive and dead" also seems like the kind of trouble you can get into when you carelessly translate physics into everyday terms. "There are temporarily two cats, one alive and one dead" might not be a terrible alternate translation, and completely sidesteps the "disproof" here. If your contradiction hinges on which words you choose to qualitatively describe the math, it's not a very good disproof.

What no you shouldn't say that, there aren't two cats in classical OR quantum mechanics. In no set of physics laws do you get two cats.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby johnny_7713 » Mon Sep 08, 2014 7:42 am UTC

I don't know that much QM, but isn't the alive/dead cat just a proxy for saying that the atom that triggers the poison gas is in a superposition of decayed and not decayed? Thus the cat itself is never actually in a superposition, even though it functionally is from the perspective of someone outside the box.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Robert'); DROP TABLE *; » Mon Sep 08, 2014 12:00 pm UTC

Since the state of the cat's tightly correlated to that of the atom, either both or neither of them should be in superposition.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Mon Sep 08, 2014 2:38 pm UTC

It's not that tightly correlated. There's a whole bunch of experimental apparatus in between; that is the resolution. The cat is only in a superposition if you do not decohere the superposition somewhere along the line.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Whizbang » Mon Sep 08, 2014 2:52 pm UTC

thoughtfully wrote:
douglasm wrote:As I understand it, in order for Schrodinger's Cat to be valid if actually carried out, the box would have to be so thoroughly isolated that not even so much as the state of a single photon outside the box could be affected by the cat's life or death before opening the box. Setting this up would be difficult.

I'm pretty sure you also have to cool the cat down to a pretty ridiculous fraction of a degree above absolute zero, to keep the poor cat from decohering itself. Which pretty much renders the whole exercise moot.


I once froze a cat to absolute zero. It was 0K.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Quizatzhaderac » Mon Sep 08, 2014 3:47 pm UTC

doogly wrote:In no set of physics laws do you get two cats.
You get two cats in the many worlds interpretation of QM.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Mon Sep 08, 2014 3:57 pm UTC

Not really. "Counting" "branches" or "worlds" is too naive. State of the art Everett doesn't really do that.

(Not because it has really satisfying answers, of course; it just avoids repeating obviously problematic things.)
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tyndmyr » Mon Sep 08, 2014 9:26 pm UTC

gmalivuk wrote:If your argument appears to disprove the most successfully and precisely confirmed scientific theory ever devised, your argument is probably wrong.


In addition to this, I feel it important to point out that this is merely an analogy devised to explain quantum mechanics(which are quite unintuitive, IMO). Quantum mechanics isn't really about cats, this is just a way to attempt to explain quantum behavior in a more familiar setting. I think several previous posters were attempting to say something along this line as well, but I think it's worth being made explicit.

I do find it mildly amusing, though, when people assume QM is based on a whole bunch of mathmeticians overlooking some incredibly obvious bit of math.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby gmalivuk » Mon Sep 08, 2014 10:00 pm UTC

I wasn't talking about cats, I was talking about double slit and entanglement experiments.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tchebu » Mon Sep 08, 2014 11:17 pm UTC

Let there be a sample space which encompasses every object.
Let the sample space be divided into two sets which do not intersect each other and are called dead and alive.


This is the problem. The whole point of QM is that you can't make such a division. For any observable with two outcomes, the full space of states also contains linear combinations of the observable's eigenstates.

Alternatively, if you want to just randomly cut the space of states in two and call one piece "alive" and the other "dead" then there's no physical observable which distinguishes the two pieces.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Zamfir » Tue Sep 09, 2014 1:38 pm UTC

doogly wrote:It's not that tightly correlated. There's a whole bunch of experimental apparatus in between; that is the resolution. The cat is only in a superposition if you do not decohere the superposition somewhere along the line.

Could you explain how a coherent and a decoherent amplifier (cat-based or otherwise) would differ from each other?

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tyndmyr » Tue Sep 09, 2014 2:51 pm UTC

gmalivuk wrote:I wasn't talking about cats, I was talking about double slit and entanglement experiments.


Sorry, talking to the OP, but agreeing with/expanding upon your response. Didn't make that adequately clear, I think.

In short, in focusing on the cat, he's...entirely missing the point of the analogy.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby ahammel » Tue Sep 09, 2014 2:58 pm UTC

Clive wrote: I understand the physics. I understand the dead cat.
Larry wrote:You understand the dead cat? But... you... you can't really understand the physics without understanding the math. The math tells how it really works. That's the real thing; the stories I give you in class are just illustrative; they're like, fables, say, to help give you a picture. An imperfect model. I mean - even I don't understand the dead cat. The math is how it really works.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tyndmyr » Tue Sep 09, 2014 3:05 pm UTC

Precisely. And the math is far from trivial. Even a brief perusal of it should convince anyone that the sort of folks who crunch those numbers have probably heard of basic set theory.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Tue Sep 09, 2014 3:13 pm UTC

It is fairly complicated, http://en.wikipedia.org/wiki/Quantum_amplifier
but it seems to be mostly a question of degree. To keep it coherent, you need all sorts of http://en.wikipedia.org/wiki/Quantum_error_correction
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Hypnosifl » Tue Sep 09, 2014 5:00 pm UTC

thoughtfully wrote:
douglasm wrote:As I understand it, in order for Schrodinger's Cat to be valid if actually carried out, the box would have to be so thoroughly isolated that not even so much as the state of a single photon outside the box could be affected by the cat's life or death before opening the box. Setting this up would be difficult.

I'm pretty sure you also have to cool the cat down to a pretty ridiculous fraction of a degree above absolute zero, to keep the poor cat from decohering itself. Which pretty much renders the whole exercise moot.

If the cat was totally isolated from the external environment until it was measured, and the final measurement looked at every particle in the box (possibly with the experiment repeated many times with duplicate cats starting in the same quantum state when the box was sealed, so one could look at the statistics of different outcomes), wouldn't there be indicators the system had been in superposition that couldn't be explained if you just assumed a classical statistical mixture of alive + dead, regardless of the temperature?

An idea that occurred to me would be to do a variant of the the delayed choice quantum eraser where the "signal" photon would leave the box from one of two slits and hit a screen, and the "idler" would remain inside, and depending on which slit the signal photon exited through the idler would either take a path that would cause it to trigger a device that would kill the cat, or it would take a different path that left the device untriggered. If the box was left sealed for some vast amount of time, enough so that when the box was opened its contents would be at maximum entropy, there would be no way to tell whether the cat had been killed by the device or whether it had lived a long life and died of natural causes--the information about the path taken by the idler (and thus which slit the signal photon had exited from) would have been "erased", just as in the delayed choice quantum eraser. So in analogy with that experiment, if this hypothetical experiment could be repeated a large number of times (with the cat inside the box being prepared in the exact same quantum state each time, and the contents of the box being measured with maximum possible precision when it was opened), shouldn't it be possible to recover an interference pattern in the statistics of signal photons on the screen, by looking at only some subset of signal photons that had hit the screen on trials where the contents of the box were in some particular end state? If so, saying "the cat was really alive or dead on each trial in that subset, we just don't know which" would be equivalent to saying "the photon really passed through either the left or right slit, we just don't know which".

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby SammySpicer » Wed Sep 10, 2014 4:43 am UTC

gmalivuk wrote:All you've shown is that there is at least one false premise. You want it to be the premise that the thought experiment is valid, but it could just as easily be your premise that 'dead' and 'alive' are disjoint and between them include everything.

I'd argue that that's a false premise even from a purely biological perspective, without ever having to bring quantum weirdness into it at all.

Another way to see how your argument is flawed is to note that it would disprove other quantum effects that have actually been observed, such as the double slit experiment (the sets are photons that go through the right slit and photons that go through the left) and entanglement (the sets are spin up and spin down particles, for example).

If your argument appears to disprove the most successfully and precisely confirmed scientific theory ever devised, your argument is probably wrong.


Please answer me two questions,
1. How can dead and alive ever intersect each other in purely biological terms, nothing can exist in both at the same time.
2. I realise that Schrodinger's cat was an example on the absurdity of the underlying theory behind it, but it is still a perfectly valid example of it. Please tell me how my premises are flawed, either axiomatically, or via reference to any accepted scientific experiment, or mathematical proof.

I am confused as to how you can find any fault in my completely reasonable assumptions, but I am open minded to any reasonable argument from you, if you are able to demonstrate one.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby gmalivuk » Wed Sep 10, 2014 4:49 am UTC

Have you read a single post in this entire thread?
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Hypnosifl » Wed Sep 10, 2014 5:22 am UTC

SammySpicer wrote:Please answer me two questions,
1. How can dead and alive ever intersect each other in purely biological terms, nothing can exist in both at the same time.

Because if we want to define "alive" and "dead" in physical terms, we would normally think of them in terms of different spatial configurations of particles--for example, a cat that's been dead for a while won't have the same oxygen levels in its cells as a live one, the membranes of its neurons would no longer be polarized, etc. But some "quantum states" involve all the particles spread out over a range of possible positions (assigning nonzero amplitudes to a range of different position eigenstates). If you measured some other non-position variables and found the system in some quantum state S1, and then immediately afterwards made a precise measurement of the position of all the particles in the box, according to the quantum rules this would put the system in a new quantum state S2 which was a position eigenstate, with the probability of getting a given position eigenstate proportional to the square of the amplitude assigned to that eigenstate by the first state S1. For some choices of S1, there might be a 50% chance that the position measurement would give a new state S2 whose configuration would be labeled "live cat", and a 50% chance it would give a new state S2 whose configuration would be labeled "non-living remains of a cat". In such a case, how should we classify the first state S1, given that in this state the atoms simply don't have a definite position configuration, and if we immediately measure their position there is a 50% chance of finding a configuration that's a live cat and a 50% chance of finding one that's the non-living remains of a cat?

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Angua » Wed Sep 10, 2014 7:16 am UTC

I realise this is slightly missing the point of the thread, but still.

What is the definition of life?
Is a virus dead or alive?
Is a prion dead or alive?
Is a self replicating program dead or alive?
What is the definition of death?
When do you class something as being dead?
Does brainstem death count as being dead?
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Zamfir » Wed Sep 10, 2014 8:05 am UTC

doogly wrote:It is fairly complicated, http://en.wikipedia.org/wiki/Quantum_amplifier
but it seems to be mostly a question of degree. To keep it coherent, you need all sorts of http://en.wikipedia.org/wiki/Quantum_error_correction

This what I deduced from wikiing around:

The state of a qubit needs two real numbers to be described, analogous to a spherical coordinate system. Might be 2 complex numbers plus some normalization, or two angles, etc. If you know the state, you can calculate the probability that a certain measurement will yield a '1' or '0' outcome. That probability itself could be used as one of the numbers to describe the state of the qubit, but then you still need another number as well , something like a phase angle.

If you describe qubits only with such probabilities, you will be tempted to use the laws of probability to calculate the effect of interactions between qubits. This will give wrong results for some situations, seemingly paradoxical.

Next, a quantum amplifier is some largish set of qubits that with tightly correlated states, and where the evolution of those states stays correlated .This is hard to pull off. AFAICT, you can only correlate full quantum states with other quantum states . You cannot, even in principle, build an amplifier that teases the qubit state apart so that two dials each show one of the angles that together describe the state of the qubit. But I am fuzzy on this aspect.

Now, Schrödinger's cat, where I am getting even fuzzier. At its core is a nucleus that might decay. I don't know if that could be interpreted as a single qubit? Even if it is, then the original description of the experiment does not aim to correlate the cat with the entire quantum state of the qubit. There is a probability of a dead cat, but no phases.

If I get this right, then there is no reason to treat the box with cat as a quantum system. You can think classically, 'the cat is either dead or alive with probability X', and every experiment will give unsurprising results from that POV. Unlike a qubit, where you can see surprising results. But someone with mad skilzz and liquid helium might conceivably build a macroscopic system that correlates with the complete quantum state of of a qubit. Such a system could only be described as being in A and B at the same time, for states A and B that we hot humans can observe. But it's less clear that such a cold and slow system could have meaningful 'dead' and 'alive' states.

Is this wikideduction somewhat correct?

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby doogly » Wed Sep 10, 2014 11:20 am UTC

Yes excellent very good.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Zamfir » Wed Sep 10, 2014 12:30 pm UTC

Thanks. A last question:

In the original thought experiment, the quantum event is a decaying nucleus. To my untrained eyes, such an event feels rather big and irreversible, compared to textbook examples of quantum states, like spin directions or electron energy levels. Is that right? Or are there real life experiments where a nucleus is clearly in a superposition with its decayed version, leading to some sort of interference effect?

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Hypnosifl » Wed Sep 10, 2014 1:11 pm UTC

Zamfir wrote:If I get this right, then there is no reason to treat the box with cat as a quantum system. You can think classically, 'the cat is either dead or alive with probability X', and every experiment will give unsurprising results from that POV. Unlike a qubit, where you can see surprising results. But someone with mad skilzz and liquid helium might conceivably build a macroscopic system that correlates with the complete quantum state of of a qubit. Such a system could only be described as being in A and B at the same time, for states A and B that we hot humans can observe. But it's less clear that such a cold and slow system could have meaningful 'dead' and 'alive' states.

As I said in my comment to thoughtfully, I don't think it's actually necessary to the thought-experiment that the system be cold, although if we wanted to correlate a macro system with a qbit in practice it would have to be cold to prevent decoherence from interactions with the external environment. But just as a thought-experiment, if we imagine some sci-fi force field that can completely isolate the cat from decohering interactions with the environment outside the box (which no realistic box at room temperature could do), and we also have a way to measure the complete quantum state of all the particles inside the box at the instant we open it (as opposed to just a coarse-grained macro measurement), and we have the capability to repeat the experiment many times with the contents of the box including the cat being prepared in precisely the same quantum state at the start of each one, then in principle I think the statistics of different end states would show correlations that would demonstrate the macro system was entangled with the qbit.

Another point is that a warm but completely-isolated-from-the-external-environment system might not be possible to create in practice, but if we had a sufficiently large quantum computer it should be possible to simulate such a system using a set of (cold) entangled qbits, since a quantum computer is supposed to be able to simulate any physically possible quantum system (much more efficiently than a classical computer).

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby ahammel » Wed Sep 10, 2014 2:09 pm UTC

SammySpicer wrote:1. How can dead and alive ever intersect each other in purely biological terms, nothing can exist in both at the same time.
"Dead" and "alive" are not well-defined in purely biological terms.
2. I realise that Schrodinger's cat was an example on the absurdity of the underlying theory behind it, but it is still a perfectly valid example of it. Please tell me how my premises are flawed, either axiomatically, or via reference to any accepted scientific experiment, or mathematical proof.

I am confused as to how you can find any fault in my completely reasonable assumptions, but I am open minded to any reasonable argument from you, if you are able to demonstrate one.
One of your premises is that the cat cannot be dead and alive at the same time. It is not terribly surprising that from this premise, you can derive the conclusion that the cat cannot be dead and alive at the same time.
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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tchebu » Wed Sep 10, 2014 3:47 pm UTC

I am confused as to how you can find any fault in my completely reasonable assumptions, but I am open minded to any reasonable argument from you, if you are able to demonstrate one.


As was pointed out, one of your assumptions is that "Dead" and "Alive" are disjoint sets whose union is the entire space of states. This is simply not the case in quantum mechanics. There is also a whole plethora of "superposition" states. You should not think of these states as "the cat is both dead and alive simultaneously" in the usual set theory sense. These are NOT states which are in the intersection of "Dead" and "Alive", there is no such intersection by assumption. Rather these are additional states which have the peculiar property that repeated interactions with researchers (using a brand new radioactive sample each time and resurrecting the cat if need be) leads to a statistical distribution of outcomes rather than the same answer over and over.

So now you can ask "How can superpositions exist? Why don't "Dead" and "Alive" exhaust my space of states?" which seems like a "completely reasonable" thing to say because we only ever see live cats or dead cats. One answer is to just point to the body of experimental evidence for QM and say "yeah, I dunno, it's kinda weird, but true, get used to it". Another is to point out that your assumption isn't as reasonable as you say to begin with. The fact that we only ever see live of dead cats only allows us to say that our interactions with cats only ever leave us with the perception of a live cat or a dead cat. This could be because "dead" and "alive" are the only two states the cat is ever in, but it also could be that the dynamics of the universe are such that the cat's interactions with the rest of the universe, and especially with us during our observation of them, tend to quickly shove them into the vicinity of those states and tend to keep them there, thus hiding a huge extra set of weirder states from our everyday experience. Both of these alternatives look the same to us in everyday life, so which one is true becomes an empirical question to be studied in more exotic experimental settings. That's where we point to the body of experimental evidence for QM and say "oh, I guess it's that second case... kinda weird, but true, get used to it".
Our universe is most certainly unique... it's the only one that string theory doesn't describe.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby speising » Wed Sep 10, 2014 9:34 pm UTC

Zamfir wrote:Thanks. A last question:

In the original thought experiment, the quantum event is a decaying nucleus. To my untrained eyes, such an event feels rather big and irreversible, compared to textbook examples of quantum states, like spin directions or electron energy levels. Is that right? Or are there real life experiments where a nucleus is clearly in a superposition with its decayed version, leading to some sort of interference effect?


i think that the point is that the decay of a single nucleus can not be predicted, it is truly random. thus, you cannot possibly know the state of the system without observing it.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby elasto » Thu Sep 11, 2014 3:17 am UTC

Honestly, I don't know how this thread survived the first reply. GM seemed to shoot it down when he mentioned that this 'argument' would 'disprove' the double-slit experiment.

Here's an attempt to construct that argument, using exactly the same wording as best I can:

Let there be a sample space which encompasses every direction a photon could go.
Let the sample space be divided into three sets which do not intersect each other and are called '(went through the) left slit', 'right slit' and 'neither slit'
A photon is created.
QM states that the photon hasn't gone in one single direction unless we observe it
This means that the photon doesn't exist within the set 'left slit', 'right slit' or 'neither slit' and so doesn't exist inside the sample space which encompasses every direction. Which means that the photon doesn't exist.

But this is absurd, as the photon was created.
Ergo, QM is disproved.

Q.E.D


As with the original 'argument', there are many criticisms that could be made, but the most damning is that the experiment has been done! Photons created one at a time still produce an interference pattern, meaning they, in some sense, do go through both slits at once, and so very definitely don't have just a single direction of travel.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby Tyndmyr » Thu Sep 11, 2014 3:45 pm UTC

ahammel wrote:
SammySpicer wrote:1. How can dead and alive ever intersect each other in purely biological terms, nothing can exist in both at the same time.
"Dead" and "alive" are not well-defined in purely biological terms.
2. I realise that Schrodinger's cat was an example on the absurdity of the underlying theory behind it, but it is still a perfectly valid example of it. Please tell me how my premises are flawed, either axiomatically, or via reference to any accepted scientific experiment, or mathematical proof.

I am confused as to how you can find any fault in my completely reasonable assumptions, but I am open minded to any reasonable argument from you, if you are able to demonstrate one.
One of your premises is that the cat cannot be dead and alive at the same time. It is not terribly surprising that from this premise, you can derive the conclusion that the cat cannot be dead and alive at the same time.


Another scientific theory disproven by the living dead, of course. :D

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby WibblyWobbly » Fri Sep 12, 2014 3:25 am UTC

Tyndmyr wrote:
ahammel wrote:
SammySpicer wrote:1. How can dead and alive ever intersect each other in purely biological terms, nothing can exist in both at the same time.
"Dead" and "alive" are not well-defined in purely biological terms.
2. I realise that Schrodinger's cat was an example on the absurdity of the underlying theory behind it, but it is still a perfectly valid example of it. Please tell me how my premises are flawed, either axiomatically, or via reference to any accepted scientific experiment, or mathematical proof.

I am confused as to how you can find any fault in my completely reasonable assumptions, but I am open minded to any reasonable argument from you, if you are able to demonstrate one.
One of your premises is that the cat cannot be dead and alive at the same time. It is not terribly surprising that from this premise, you can derive the conclusion that the cat cannot be dead and alive at the same time.


Another scientific theory disproven by the living dead, of course. :D

Zombies make especially good string theorists, of course - they're always looking for branes.

I'm so very sorry for that.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby akidbelle » Thu Nov 27, 2014 4:05 pm UTC

Hi, I did not go thru the whole thread so maybe I'll say something redundant.
The main premise of the experiment is that the cat can be isolated. It takes 500 light years of lead to stop 50% of the natural neutrino flux.
So one cannot isolate the cat before it makes a black hole...

So when mind experiments out-pass the physical possibilities of the universe, maybe there is some hidden law that we ignore.

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Re: Schrodinger Cat Disproof (Samuel Jacobs)

Postby drachefly » Thu Dec 04, 2014 5:15 pm UTC

Paragraph 2: Yes, neutrinos present a non-fundamental limit on the size*duration of a coherent state. However, neutrinos do not interact rapidly with the cat (to put it mildly), so this degradation will not be very quick. Easily long enough to perform the experiment and run up against much more fundamental limits of the problem

Paragraph 3: I have no idea what 'black hole' is doing here.

Paragraph 4: As noted above, this is non-fundamental, and the questions the problem seeks to probe are far more fundamental.


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