Einstein and Schrodinger's Quest for a Unified Theory led to a Titanic Clash 172
StartsWithABang writes When it comes to the very nature of quantum mechanics — about the inherent uncertainty and indeterminism to reality — it's one of the most difficult things to accept. Perhaps, you imagine, there's some underlying cause, some hidden reality beneath what's visible that actually is deterministic. After all, a cat can't simultaneously be dead and alive until someone looks can it? That's one of the problems that both Einstein and Schrödinger wrestled with during their lives. An investigation of that story, their work on that front, and their friendship that ensued as both pursued that same end is thoroughly investigated here by physicist Paul Halpern.
Is there a fixed length for he (Score:5, Funny)
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yes just what is a Titanic Cl ?
Is it chlorine ?
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If it had been "CF" I would've understood it.
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The headline is chopped and non-chopped at the same time. It collapses into a concrete state when an article dupe is later made.
Titanic Cl (Score:5, Funny)
Iceberg Incom
Sure (Score:3)
"After all, a cat can't simultaneously be dead and alive until someone looks can it?"
Why not? After all, falling trees make no noise when nobody's watching and bears also do not shit in the woods.
Re:Sure (Score:5, Interesting)
Here is what is now thought when science is done. An observation is made. If we take Galileo as an example, he observed bones in animals. Then We make a mathematical model. In that case it was the relationship between mass the bone volume that was needed to support the mass. Then we make testable predictions based on that model, Galileo made the prediction that Giants do not exist, which is true, and could not have existed, which is one of the things that made the Church mad.
Relativity and Quantum mechanics both depend heavily on the mathematical model to make predictions on things that are not part of our everyday experience. This is different from classical physics where the mathematical models were based on things that most people observe. Classical physics is a ball falling and bouncing off the floor or light refracting through a prism. Quantum mechanics is a ball tunneling through the floor or light refracting around a galaxy. What I find interesting is that people take Relativity at face value and have a problem with Quantum Mechanics. It is true that we see a limit in velocity in the macroscopic world, but that has to do with friction, not relativity. There is nothing in our experience that says we cannot go as fast as we have the energy to accelerate. Certainly our mass does not increase if we are traveling at 80 miles and hour in a car instead of 30 miles an hour.
OTOH, our experience does tell us that second and third hand information is unreliable, and we are often better off making direct observations if possible. Are we just going to let some stranger bury our cat on the statement the cat fell off the roof and died? No, we want to see the cat, and until we do we hope the cat is alive, but there is chance the cat is dead. Is it both? No, it is uncertain, which is the key thing that people do not learn about science. Uncertainty.
In Quantum Mechanics this is called a wave function, and the cat is in a superposition of wave functions that represent all possible states. The wave function collapses when we make an observation.
Here is another interesting thing. Quantum Mechanics came about to a problem with infinity. Relativity never solved it's problem with infinity, at least not completely, and when combined with Quantum Mechanics develops more infinities. This is what does not make sense.
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People don't take relativity at its face value either. It has features that people tend to accept, and features that people tend not to. People who say they have no problem with relativity will still believe in absolute time and simultaneity. They have no problem with the ideas of effective mass increasing with speed, or time slowing (although they tend not to realize it's symmetrical), or length contraction, as long as they realize these effects are imperceptible in everyday life.
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Or it doesn't, it simply seems that way because all our instruments of observation - both natural and artificial - are specifically designed to report a cat as either alive or dead but not both. In other words, the cat doesn't stop being in superposition, but rather we enter a superposition of seeing a living cat
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I'm doing my best to cure Virgos.
God doesn't play dice, he plays blackjack (Score:3)
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The fucking cat (Score:5, Informative)
No, of course the cat can't be simultaneously alive and dead - that's Schrödinger's point.
I wish people would stop crapping on about that fucking cat when they have no idea what it means.
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I was going to comment on the irony of your statement, but then I wondered if you could be both right and wrong at the same time...
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Schrödinger's point was not that the cat couldn't be both alive or dead. It was that if quantum theory was correct that that would be the absurd conclusion.
So is quantum theory correct?
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It was that if [the Copenhagen interpretation of] quantum theory was correct that that would be the absurd conclusion.
In many worlds we just don"t know what universe we're living in before we open the box.
Re:The fucking cat (Score:4, Informative)
So the Copenhagen interpretation is wrong, as is any other interpretation that necessarily comes to the same absurd conclusion.
The interpretations that don't make such a conclusion are unaffected by the thought experiment.
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The problem is, the conclusion is not absurd. It's merely unintuitive. For it to be absurd, the Copenhagen interpretation itself would have to require cats to be either alive or dead but not both as its premise. It doesn't, so showing it necessarily leads to living dead cats doesn't disprove it. Neither has any actual observation done so to date.
Common sense is a good thing to have
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Like I said in another post [slashdot.org], no it won't. Observing something is merely the act of making your own wavefunction correlate with theirs. If someone observes the status of the cat, they're now in a superposition themselves: if asked about the cat, they might say it's alive or it's dead. We don't know which until asked, at which point we think we got a definitive answer but in re
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This gets modded +5? (Score:3, Informative)
Yes, you remember the half of the story that most people forget, but that is useless without the whole story.
The point of the Schrodiner's cat experiment was to be a reductio ad absurdum argument, except it turned out that quantum mechanics is quite absurd by comparison to most physics interacted with on a day-to-day basis. That doesn't mean the cat is not both dead and alive. It turns out that quantum mechanics does allow for macroscopic superposition of states that are suitably isolated
So yes, the cat
Re:The fucking cat (Score:5, Informative)
I wish people would stop speculating about the fucking cat and just read what Schrödinger wrote [www.tuhh.de]. Come on, it's four paragraphs.
What Schrödinger is doing is pointing out how ridiculous it is to accept the "quantum blurring" because "it only affects microscopical particles anyway and they're just weird". The problem is that one cannot consistently keep the blurring confined to the atomic domain. As Schrödinger points out very clearly, if we accept that the atomic nucleus is "blurred", then this blurring can be easily amplified to the macroscopic domain and make the cat be simultaneously dead and alive. Since we don't observe cats to be blurred, we cannot accept atomic nucleus to be blurred.
That's what Schrödinger states one line after introducing the fucking cat. Since I know nobody is gonna click the link and RFTA I'm going to quote:
It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a "blurred model" for representing reality.
Re:The fucking cat (Score:5, Informative)
We can't observe "quantum blurring" either. If we do the two-slit experiment with electrons, and measure which electron goes through which hole, they'll act just like particles. It's only if we don't observe electrons as particles that we can get interference patterns. We can't directly observe a particle being in an indeterminate state, but we can measure its state by translating it into something way above the photon level, like a photon detector or a cat. (Under ideal conditions, you've got about a 50% chance of detecting a burst of about 100 photons. This is as close to direct perception on the quantum level as you can get.)
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This is true; a measurement always returns a definite result, never a "smearing" or a "blur". But I'd like to point out that the issue is a bit deeper, as there is no physical distinction between "determinate" and "indeterminate" states. For example, a photon with vertical polarization is in a "determinate" state if you measure it in the vertical/horizontal basis. But if you measure it in the diagonal/antidiagonal basis it is in a "indeterminate" state, a equal superposition of diagonal and antidiagonal.
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We can't directly observe a particle being in an indeterminate state
And this central mystery is still with us: why can't we? Decoherence people sometimes claim to have the answer, but they don't: they can explain why we don't see interference, not why interference is the only way we can be aware that particles are in indeterminate (classical) states.
Reality is very strange.
Well that was quick. (Score:3, Informative)
More hipster site spam from a serial hipster spam poster. Don't even need to read the summary, since it's all clickbait shoddily cooked up from other people's work anyway.
Not Hard To Imagine (Score:4, Interesting)
If "universe" is locally predictable in one direction (which becomes "axis of time"), then self-replicating features (life) can emerge. In the case of our universe, there is atomic/molecular level complex and yet locally perfectly predictable, that enabled (under "perfect circumstances"?) life forms. atomic/molecular level isolates low level quantum weirdness. After all, life doesn't care if this function is predictable at ALL levels, molecular level is enough, and it happens to be good for many other reasons. There is so many random things needed for universe to sustain life, that probably insignificantly small portion of functions has any self-replicating (living) features, let alone intelligent.
Why should I be surprised by weirdness of quantum world then? It never needed to be predictable in our direction of time.
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Yeah, I've with you in most respects. Science seems to blinkered in the belief that time has only one direction. Time is a construct of our interpretation of the universe. It is not an forcing acting upon anything. This is why is can't be detected. Much like gravity and the ever elusive graviton! So ultimately, if we don't understand gravity, we're not going to understand time.
There's some big thinkers out there who don't make this assumption of one-directional time in the electrical engineering disci
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Re:Not Hard To Imagine (Score:4, Informative)
Science seems to blinkered in the belief that time has only one direction.
Really? I'd suggest you try taking a Special Relativity course where you'll learn that relativistic effects are caused by the rotation of the space-time axes between inertial frames e.g. the reason for length contraction is because the object's time direction points partly along the observers length direction.
There's some big thinkers out there who don't make this assumption of one-directional time in the electrical engineering discipline. In doing so, they can apply this thinking to electrons, which they've found can pop in and out of existence.
Wow it's almost like they are physicists from ~60 or so years ago. I can only hope their knowledge of electronics is more up to date or do they still insist on using valves? We've known for a long time that electron-positron pairs can pop out of the vacuum. This gives rise to measurable effects such as vacuum polarization [wikipedia.org] which changes the strength of the EM force with energy and Casimir effect [wikipedia.org]. In fact Feynman actually showed that a positron (anti-electron) was equivalent to an electron with the direction of time reversed so you can indeed treat a virtual electron-positron loop as something oscillating back and forth in time.
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Ever seen a Feynman diagram? They're reversible in time. Quantum interactions are mostly simply reversible in time (some features of the weak force aren't, but there are symmetries involving forward and backward time even there). Physicists are well aware of this. They're aware that it's impossible to measure time in an absolute sense (their best ideas involve finding periodic processes that can be observed to be more or less consistent with each other, and settling on those). Since Special Relativity
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Function, that is itself probably intersection of multiple functions, some of them being evaluated backwards of what we percieve as "time", therefore creating weird effects in our perceived direction of time.
That's already really weird man. You're essentially saying some parts of the universe are traveling forward in time, while others are traveling backwards.
The real question here (Score:2)
Is the cat "somebody" or not? Because if it is somebody, it can look itself. It may also be a "semi-somebody", that has the action of "looking" fail some times and succeed sometimes. All it this quantum-babble really boils down to is the question whether the cat is sentient or not. Now, most young children will count the family cat as a person, albeit a somewhat different one, but most certainly a sentient. The problem here is that young children may not have full sentience themselves and hence that evaluat
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What? No. The question is not whether the cat is sentient, or even alive or dead. The question is whether the action of a sentient being is special and the universe somehow bends its behavior to acknowledge our presence.
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Aaaaaand, fail. You seem to need a refresher course in basic quantum mechanics.
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What I'm saying is, everybody takes the wrong thing from that thought experiment, including you. The point isn't that we really wonder about the poor cat, or what's going on with it. The implication of the whole thought experiment is that something which is clearly impossible (a cat being alive and dead simultaneously) seems to be a natural consequence of the things we observe in quantum mechanics. An observer shouldn't change the way fundamental objects behave. Whether a photon is a particle or a wave shou
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Actually, you are wrong: While you think this is "clearly impossible" there is nothing clear here and it is completely unknown whether this superposition of states is possible or not. On quantum-level it is, but quantum-effects apparently do not scale up. The one thing that is clear is that for sentient beings above a certain level, the superposition is impossible, because if it were possible the person in it would immediately collapse it. For inanimate objects it is not a problem at all having a superposit
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Actually, you are wrong: While you think this is "clearly impossible" there is nothing clear here and it is completely unknown whether this superposition of states is possible or not. On quantum-level it is, but quantum-effects apparently do not scale up.
So, have you ever experienced a cat being alive and dead at once? Can you ever, really, imagine this happening with anything you experience directly? Just because you can say the words doesn't mean you understand something. This is one of the most fundamental tenets of formal logic - you cannot occupy two mutually exclusive states of existence at the same time. It cannot be raining and not raining. A cat cannot be alive and dead.
Nevertheless, QM makes it abundantly clear that this happens all the time in th
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You stance is called "denial". Apparently you have no understanding the scientific process at all, and your insistence to only accept what you can personally observe or imagine reveals a limited mind. While those limitations may be acceptable to you, you insistence that others should share your limitations makes you a problem. Please go away, live in a cave somewhere or something.
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Nice call on making a bunch of ad hominem attacks. It makes it clear that you don't have anything substantive to add to the conversation. Saves us both time.
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If you think that sentience and QM have anything to do with each other, then you are living in fantasy land.
QM has a precise mathematical description, while the concept of "sentience" has never been defined in any meaningful sense.
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Really, you are quite off the mark. But what do you expect from an AC obviously full of himself.
The cat is Dead (Score:2)
How many cats live to be 80 in cat years, never mind human years.
Now that is quantum uncertainty...
The model is not reality (Score:3)
People forget that. But that doesn't mean the model can't be useful as a conceptual framework or have predictive power if t conforms closely enough to actual data.
Nice story, but misleading (Score:2)
I never knew that Schrödinger joined at some point in Einstein quixotic quest for a classical unified field theory. Cool story, bro.
But I'm annoyed about the portrait of Schrödinger as Sancho Panza to Einstein's Don Quixote. Schrödinger was a major genius! He invented quantum mechanics, for fuck's sake! I'm particularly riled up by the statement
Embarrassed by the incident, Schrödinger would give up his quest for unity altogether and turn to other topics. Similarly, he would never collaborate again with a prominent physicist.
This seems to imply that Schrödinger never accomplished anything after he stopped collaborating with Einstein. Well, he helped discover DNA. [wikipedia.org]
Titanic CI? (Score:2)
Customer Intelligence? Continual Improvement? Counterintelligence? Channel Islands?
So who was the iceberg. (Score:3)
If I lock up Einstein, Schrodinger and Heisenberg in a room with a capsule of cyanide gas and a time release mechanism for the gas, would I be sent to jail? Or to the mental institution?
Bad analogy (Score:3)
Schroedinger should have chosen a different animal than cats, you know, 9 lives and so.
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A light cruiser that hit an iceberg in 1912?
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Re: Coincidental Ratios (Score:2)
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Stupid post modded up yet again (Score:5, Informative)
5. And thus it is detected ALL THE TIME BY EVERYTHING AROUND IT, long before you put it through a diffraction grating, or whatever test you dream up.
Stop using the pop-sci version of things where it is about being "detected" or not, and it comes down to whether it interacts with things in specific ways. Turns out the fact it has a magnetic field, or even that the wavefunction has infinite extent, doesn't cause it to be "detected" and there are plenty of ways interactions that can happen without "detection," whether with things like the slits in a double slit experiment, or more explicitly involving magnetic fields like the Aharonov–Bohm effect.
It's not, I know its not, but without my glasses, I can no longer see the individual birds, only a cluster big enough to fire the nerve in my retina.
That description would be apt, except for the fact that some interactions will then cause all of the birds at other locations to instantly disappear, or to change into other states. If readers are curious, they can look for much longer rebuttals of this in response to many of your other posts, but it makes it look like you've only read about quantum mechanics from news outlets, and not an actual text book or class notes.
They can only be created and observed that way, so they must only exist that way.
Oh, maybe your the same AC that has been saying photons can only be created or seen by discrete processes of changing electron levels in atoms. That is flat out wrong, as there are several processes the photons can be created or detected by, some of which are continuous (e.g. scattering and bremsstrahlung).
I think the sun and planets go around the earth, I make an equation to explain the weird loop-the-loops that planets do.
Of course you can make an equation with "loop-the-loops" or epicycles, but the only way to get it to match observations would be an infinite series that ends up matching the actual paths they make around the sun. Just like any function can be broken down into components by Fourier transform or many other transforms, whether or not it makes sense to a given situation, but you still make the same predictions in the end with the full series.
But go ahead, keep reposting your BS, over the last couple years you've managed to get +5 before someone notices sometimes, or even get a few by without any replies if you post them to a story late enough.
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IANAP, but I'll give this one a bash.
Interactions with other stuff *IS* detection.
Detection/interaction is not the same as measurement (determination) of a quantum property, such as location, momentum, or spin. You can measure an electron's location with varying degrees of accuracy, if you so wish, and it's provably not a limit due to your measuring equipment. You can detect the presence of an electron without collapsing its spin to a definite state.
6. Thus your Quantum uncertainty theory can never work, the particle/photon/whatever's state MUST be determined BEFORE *you* detect it by its interactions with other matter.
Wrong. Not all interactions collapse the wave function, and that's one of the great mysteries still bei
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Something can have influence, and the effects of that influence can be undetected. If an electron can exist with indeterminate spin, why can't the effects of its electromagnetic field be indeterminate?
Let's look at the two-slit experiment. If we try it in ordinary life with a machine gun, so we're putting things known to be particles through, the hit distribution is the sum of the distributions from each slit. If we try it in ordinary life by putting it in water and making waves through it, we get an
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"Wrong. Not all interactions collapse the wave function, and that's one of the great mysteries still being explored."
That's faith in mysteries not proof.
No it's not, it's a perfectly factual statement.
It's magnetic influence is dependent on its spin, and thus it already determined because it has an influence before you detect it.
No. You can establish the location of an electron - detecting it - without determining its spin.
"Your reasoning seems to amount to "
You misrepresent the explanation.
You haven't offered any explanation. Of anything.
" But it won't be long before someone comes up with a simpler one that better fits the observations"
Indeed, and that simpler equation will meet opposition from believers in the old equation. That's you.
How can it "be me"? You haven't offered a simpler explanation for me to consider. Your "simpler explanation" - which apparently amounts to a simple pig-headed insistence that there are hidden variables, in direct contradiction to oft-repeated experimental results - has no evidence in its favour. Simple it may be, but
Some Basic QM (Score:3)
Your photon has a magnetic field, and that influences the matter around it, depending on its wave function....And thus it is detected ALL THE TIME BY EVERYTHING AROUND IT
Sorry but that is just wrong. Photons do indeed contain an EM field but the photon is small in size. In addition the interactions are quantum in nature i.e. they either happen or they do not. You cannot use your simple, classical view of physics to assume that there is an EM field and so therefore there must be an interaction: the universe does not work like that.
Many of the high energy photons we produce in the ATLAS experiment at the LHC will travel through multiple layers of silicon before they inter
Quantum Field Theory (Score:3)
This is a statement of your faith in QM. It is a religious statement not a factual one.
No actually it is a factual statement which has been tested to a precision better than one part in a trillion [wikipedia.org]. In fact it is one of the most precisely tested scientific theories ever discovered. Have you tested you theory on how things work to that level of precision? Have you even figured out what the predictions of your theory are to that level? In fact have you ever done any experiment whatsoever which has agreed with your ideas and disagreed with QM? If not then I think it is extremely clear who is tak
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My point being you *detect* that interaction or you do not, and the quantum effect is the limit of your *detector*, not in the interaction.
That's not your "point," it's your uneducated hunch.
Do you honestly believe that you, from your armchair in the basement, have got it right where generations of physicists have got it wrong?
Can I come to the ceremony when you get your Nobel prize?
Re:Flock of Starlings (Score:4, Insightful)
1. if detecting a particle *determines* its state vs *observes* it state, (the main point of conflict) then:
2. There is no perfect isolation, a vacuum is not perfect, and does not shield magnetic fields or other effects.
3. Interactions with other stuff *IS* detection. That other stuff does get influenced depending on the state of the particle. The magnetic field does influence the world around it.
4. Your photon has a magnetic field, and that influences the matter around it, depending on its wave function.
5. And thus it is detected ALL THE TIME BY EVERYTHING AROUND IT, long before you put it through a diffraction grating, or whatever test you dream up.
6. Thus your Quantum uncertainty theory can never work, the particle/photon/whatever's state MUST be determined BEFORE *you* detect it by its interactions with other matter.
Interesting argument, but I'm not sure that I agree on point 3. We've got a number of very subtle experiments that have tried to tease out exactly where the observer effect starts and ends. Bell's Theorem and EPR prove that no hidden variables exist, so these properties are not things that are stored and just discovered when we check - the behavior that's observed can only be explained if they "decide" what to be when we make a measurement.
Also, consider things like the quantum eraser, and delayed-choice quantum eraser - it seems like the universe is keeping track of what we are looking for and how, such that we can "detect" a particle, destroying the wave-nature and interference pattern, but then "erase" our knowledge of the detection, and see the wave-nature restored.
Finally, with your point about the bricks, you seem to be saying that maybe half-particles exist but we can't detect them because of limitations of our instruments - but discrete, quantum-mechanical behavior extends to far more than just particle counts and even positions. The Stern-Gerlach apparatus being a clear counterexample to your point. The behavior observed there doesn't depend on dealing with any particular number of particles - it just shows that particle spin is entirely quantized, since the particles passing through are deflected entirely one direction or another. We could readily detect particles which were deflected partially, according to continuous, classical behavior - if they existed.
Ultimately, you've got a good argument if all your suppositions are true, but we've got experiments that prove quantum uncertainty as well as anything has ever been proven. In the words of Feynman: "It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong."
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Well SG always bugged me because the magnetic field only affects the spin that is in the axis relative to the field, yet even if it was quantized why would it nicely have spin related to the field? So even if it was quantized, if you were actually measuring the spin you'd still expect it to deflect by different smooth amounts, depending on the orientation of the spin to the field. The fact its a fixed amount surely means you are not measuring a spin effect AT ALL. Quantized or not.
The most provocative thing about Stern-Gerlach is that it suggests spin orientation itself is quantized, not just magnitude. You seem to object to this interpretation, but I don't see you providing any alternative. I'm inclined to go with the established consensus among quantum physicists.
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You don't even need to predict infinitely far ahead... for example:
if this program's else clause will execute, then take branch A, else take branch B.
Regardless of what information you allegedly have about the program's future state will be incorrect, so it is trivially provable that no amount of information can be sufficient to even predict the future in a simple closed experiment such as this, and if even a single experiment
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You can ask whether the else clause will be executed within the next N steps, N being any finite number and "step" being one basic computational step or some other finite and nonzero measurement. (If nothing else, you run it for N steps, and see.) You cannot in general know whether that else clause will ever be executed. If you have a reasonable definition of complexity, you can probably show that, in general, you can't predict N steps into the future with a method less complex than the machine itself.
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You don't even need to predict infinitely far ahead... for example:
if this program's else clause will execute, then take branch A, else take branch B.
Regardless of what information you allegedly have about the program's future state will be incorrect, so it is trivially provable that no amount of information can be sufficient to even predict the future in a simple closed experiment such as this, and if even a single experiment can be designed where the result is not predictable, the universe cannot be deterministic.
The machine is still deterministic. You can predict with 100% certainty that if the condition on the evaluation is true, it will do A, and if not it will do B. You can even determine what the condition will be by running all the steps of the program until you get to that statement. That is determinism.
The only way you could have a "computer" that wasn't deterministic would be if its operation were influenced by randomness (true randomness - not algorithmic pseudo-randomness). Such a device would not be
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A universe being nondeterministic does not mean it is impossible to construct smaller entirely deterministic systems within that framework... "if A then B" can be entirely determistic, even if the universe which runs it is not, if no aspects of the universe's non-determinism impact the execution of the statement.
Sure, I'll buy that. However, in practice if the universe contains elements that are non-deterministic, it seems extremely likely that the physical construction of a computer would not be entirely free of those elements.
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I'm suggesting that with such an experiment, it wouldn't matter how much resources it required... even if the amount of resources were infinite, the results of the prediction would *always* be wrong, because the experiment is explicitly design
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As I said.... "if this program will take branch A after executing this statement then take branch B, else take branch A" where branches A and B are mutually exclusive is an extremely simple example of a system where no amount of information will be sufficient to predict its conclusion, and if an experiment can be derived whose outcome cannot b
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I didn't put the word ever in there because I didn't mean ever... I meant the results of *THIS* test, and no other. I don't care what happens any other time I run the test, I want to know the results of *THIS* test. If the universe is deterministic, then at any point in time, then it must contain sufficient information in its state to predict some future state, and that information is the only input to the algorithm. The fact that any such agent which tries to examine such a state may never stop trying
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The halting probability is much more interesting; a number within the set of real numbers which can never be found by any algorithm or computation. Its proof that the set of real numbers is larger than the set of natural numbers. All natural numbers can be found by computation.
aleph null does not equal aleph one.
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The existence of the Halting Problem disproves determinism.
The existence of the Halting Problem REQUIRES determinism. The Halting machine itself is deterministic. Given the current state of the machine, you can perfectly predict the next step of the machine. You just can't predict whether it will ever finish running without walking through the steps until it stops (assuming it does, and you'll never know if you ran it long enough).
Determinism is more about knowledge of the current state and the rules the game operates by.
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The halting problem requires a deterministic system, it does not require that the universe itself to be deterministic. The universe encompasses everything that ever was, is, or will be... including all deterministic systems.
I'll accept that definition of the universe, but recognizing that "all deterministic systems" might be an empty set.
My main point is that in a deterministic universe you should be able to contrive a deterministic thought experiment which will always be able to correctly predict the outcome of the experiment, but if you design the experiment so that its output is always the opposite of whatever was predicted, then it becomes evident that there can never be sufficient information at the beginning of the experiment to predict its conclusion, and if the current state of the universe is not sufficient to predict a future state, then the universe is not deterministic.
You're basically trying a proof by contradiction here, I believe. However, your wording is really loose.
First, what do you mean by "predict the outcome of the experiment?" What experiment?
Then you say that you "should be able to contrive" an "experiment" that can predict the outcome of the "experiment," but that it will have the "output" that is the opposite of whatever was predicted. What
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Really? What happens if you ask it to tell you if a function will terminate when the function does the opposite of whatever the halting machine says the function will do?
Still think it's deterministic?
The behavior of a halting machine can only be deterministic for certain types of functions.
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Really? What happens if you ask it to tell you if a function will terminate when the function does the opposite of whatever the halting machine says the function will do?
Turing machines only support a few instructions. It can move left, move right, stay in the same place, change state, and write something in the current position.
There is no instruction called "terminate when the function does the opposite of whatever the halting machine says the function will do." I don't even know what that means. Turing machines don't say anything - they just execute instructions.
The behavior of a Turing machine is completely deterministic. If the instruction table says to move left g
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But if the instruction table says to move left when an alleged so-called analysis of the future says it will move right
What does that even mean? The instruction table says that if the condition is A, move left, if the condition is B, move left, if the condition is C, move right, and so on. A Turing machine operates entirely in the now (just like any other conventional computer). It doesn't have to guess what it might do - it just looks at the current state, looks it up in a table, and does what it says.
If you're saying that it should try to figure out what it will do 10 steps in the future, then that is basically the hal
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It doesn't have to "figure out" anything... if the sufficient state to predict the future exists, then you could at least theoretically use some alleged "magical" black box to say whatever a future state is going to be based on the universe's current state, and just have the deterministic turing machine query that. My point is that when the turing machine is programmed to do the opposite of whatever the black box says is going to happen, absolutely no amount of information, even an infinite amount, will a
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It doesn't have to "figure out" anything... if the sufficient state to predict the future exists, then you could at least theoretically use some alleged "magical" black box to say whatever a future state is going to be based on the universe's current state, and just have the deterministic turing machine query that.
The problem with such an approach is that your machine is part of the universe, and therefore must modify it as part of performing its evaluation of the future state of the universe. The machine must also be larger than the universe to do this, since it needs to maintain in its memory the entire current state of the universe and some number of future states to perform the calculation.
Such a machine cannot exist. The fact that it can't exist doesn't mean the universe isn't deterministic. It just means tha
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Again, there is nothing that the Turing machine would ever need to figure out... it simply needs to just blindly do the opposite of whatever some black box says is supposed to happen... there is no "intelligence" behind this decision, it is simply flawlessly executing the instructions that would have been programmed into it, and the only way the box could ever be correct is if the machine were
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Again, there is nothing that the Turing machine would ever need to figure out... it simply needs to just blindly do the opposite of whatever some black box says is supposed to happen...
A Turing machine is a mathematical construction. You're trying to use the halting problem as a rationale for the universe being non-deterministic. However, the halting problem only applies to Turing machines. A Turing machine can't contain a black box, because that isn't part of the definition of a Turing machine.
It is a bit like proving that there are a countable number of integers and then trying to say that there must be a countable number of irrational numbers by just redefining the meaning of "integ
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