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Quantum Physics Parts Ways With Reality
aeoneal sends us to PhysicsWeb for news guaranteed to induce headache in those wedded to the reality of, well, reality. Researchers from the University of Vienna have shown the violation of a stronger form of Bell's inequality known as Leggett's inequality. The result means that we must not only give up Einstein's hope of "no spooky action at a distance," we must also give up (some of) the idea that the world exists when we are not looking. From the article: "[Studies] have ruled out all hidden-variables theories based on joint assumptions of realism, meaning that reality exists when we are not observing it; and locality, meaning that separated events cannot influence one another instantaneously. But a violation of Bell's inequality does not tell specifically which assumption — realism, locality, or both — is discordant with quantum mechanics." From the Nature abstract: "Our result suggests that giving up the concept of locality is not sufficient to be consistent with quantum experiments, unless certain intuitive features of realism are abandoned." Only subscribers to Nature, alas, can know what features those are, as PhysicsWeb doesn't tell us.
Entia non sunt multiplicanda praeter necessitatem. In my ever so humble opinion, Quantum Physics has long since exceeded the cut.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Am I the only one that thinks to themselves, "One of these days, some really smart person is going to come out with a new and better theory of reality that reveals all this quantum mechanics stuff to be a bunch of quackery."?
-1 Uncomfortable Truth
In Physics, to observe something means to interact with a system in such a way that it changes whatever you use to interact with it. It has nothing to do with humans looking at it. When a photon hits your arm from the sun it analogous to an "observation".
In regards to the article, I think more than a few already known quantum phenomenon make the idea of the universe not making a sound when no one is there to hear it, one of the less mind boggling ideas. Although its only mind boggling because we use our mind that evolved in a mainly classical newtonian world, yadda yadda, blah blah.
I still think Einstein's most accurate statement is that the most incomprehensible thing about the universe is that its comprehensible at all. There is no "reason" it should be or will continue to be.
So, logically, the universe is powered by photons? Or reality as we perceive it is the interaction of particles, rather than the particles themselves? I'm not seeing much of a reason to panic and start worrying that the great turtle might awaken from his dream, but maybe it's just me.
True science means that when you re-evaluate the evidence, you re-evaluate your faith.
I still think Einstein's most accurate statement is that the most incomprehensible thing about the universe is that its comprehensible at all. There is no "reason" it should be or will continue to be.
I view that as the primary form of a reverse-anthropic principle:
The universe is comprehensible because the mechanisms of comprehension evolved within it by conferring an advantage to those organisms that have them. This only occurs for those aspects of comprehension which operate correctly within the universe.
So comprehension evolves only for those aspects of the universe that ARE comprehensible enough to make useful predictions. If there are no comprehensible aspects to the universe, comprehension doesn't evolve.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
When we see an insect being tricked into thinking an orchid is a female insect we think "That orchid doesn't look anything like an insect, what a strange mistake to make", and a bat might use echo location and see us being aroused by something that simply has the texture and shape of a piece of paper which doesn't resemble the texture or shape of a female human and wonder how we could make such a mistake.
Our common sense and intuition don't necessarily tell us what's true, especially when it doesn't relate the world we evolved in, so we have to rely on experiments, and quantum theory constantly makes accurate predictions. If it's beyond our common sense and intuition then that's too bad for us.
// MD_Update(&m,buf,j);
Occam's Razor only lets you choose between two hypotheses which both adequately account for the data. Unless you've got some other theory with fewer entities in your back pocket that can explain things like the two-slit experiment and the Stern-Gerlach experiment, Quantum Mechanics is the only game in town.
Qvis?
Why is it that when you believe something it's an opinion, but when I believe something it's a manifesto?
Craft Beer Programming T-shirts
Consider a cat of the Schroedinger subspecies. In the experiment, it is neither alive nor dead until observed. A rock, positioned near the detection apparatus, can observe the result. So for the rock, the cat is either alive or dead. But until YOU observe the rock, you don't know whether the rock is happy that the cat is alive, or sad that the cat will never again rub it's tail against the quartz inclusion on the rock's lower anterior surface. The quantum wave-function describing the cat has collapsed with respect to the rock, but to you the quantum wave-function of the cat and the rock are now entangled; in fact, by observing the rock and causing its quantum wave function to collapse, you will also cause the quantum wave function of the cat to collapse... but in both cases, it is collapsing for YOU, the observer. Every other observer has to make them collapse for themselves by either observing something the cat/rock, or observing something that has already collapsed those wave-functions for itself.
Sorry man, but the universe isn't obliged to live up to the expectations that you've developed based on your highly limited experience with the laws of physics. You've observed light in the 300nm to 800nm range, you've observed matter in the 1 milligram to 10 tonne range moving at velocities in the 0.0 m/s to 600.0 m/s range, and just maybe some matter in the 10 gram to 1 microgram range moving at velocities up to 1000 m/s. But man, that ain't shit. The world contains matter moving at up to 0.999999 C, blocks of matter so cold that void of space is over a trillion times warmer, particles that change from antimatter to matter for no apparent reason, and photons energetic enough to shred the nuclei of atoms like a Kattus-Schroedingerus shreds catnip-infused kleenex. There are particles whose position is so inherently imprecise that they have trouble turning because they would start colliding with themselves (like humble electron, for example). There are gobs of matter so weighty that they curve space forming telescopes that are light-years long.
If you think you have even the vaguest conception of how the universe works, then you are inherently wrong, because Human's can't conceive of how the universe works by any means. If you even attempt to apply common sense to the universe, you'll never be able to accept any of the research that actually explains how computers, lasers, DNA, proteins, and light-bulbs work.
In fact, I have a degree in it.
... that's as much as I know.
Hey kids. Get a degree in something you love, like Latin, or poetry, or whatever.
Then go get a job doing your hobby, like computers (I'm not good enough to be a pro surfer). And keep practicing your love (yes, every kind of love).
This will prevent quantum weirdness like waking up at 35 and realizing you hate your life.
As far as the nature of reality
+1 fashionably cynical
In particular, theories are judged based on what you might call 'philosophical' notions. And in fact, the great physicists - Newton, etc. - all had very deep philosophical ideas about their theories (although those are perhaps less well-known).
As an example, we now consider Newton's law of gravity to be correct (up to relativistic considerations). Yet, at the time, many thought this to be philosophical nonsense. For what is gravity - it is 'action at a distance', with no mechanism! When a billiard ball hits another, the operation of force is clear, but why should some force exist between two billiard balls far apart? This is pretty much the same issue as the 'nonlocality' issue with QM. It took quite a lot of convincing to get the scientific world to agree with Newton's 'action at a distance', and the discussion was both practical (numbers, experiments) and 'philosophical' (how it fits into the rest of the current picture of 'reality' at the time).
Anyhow, just trying to point out that science and philosophy are not disconnected. As science gets more specialized, it may seem so, since scientists don't get any philosophical training these days (they used to, though!).
Are you saying that you can't discover new technologies using quantum mechanics because it doesn't follow common sense?
Or worse; are you saying science isn't worthwhile as a search for truth, and that scientific pursuits are only worthwhile when it helps create new products for consumption?
// MD_Update(&m,buf,j);
I wish I had mod points for you...
I've never understood why people get so hung up on having philosophical interpretations of it-- they aren't necessary or particularly useful.
Awesome retort.
Not only that. Increasingly, the new products made for consumption aren't for us to do the consuming, but instead big corporations, the government, or the military.
(Because dangit, I wanna invisibility cloak too.)
"Or reality as we perceive it is the interaction of particles, rather than the particles themselves?"
Funny you should say that.
Ever since I started studying physics/chemistry in high-school (at about the same time, 5th grade or so), I stopped thinking of "matter" as the defining issue, and started focusing on interactions between them almost exclusively.
It makes no difference wether a particle/molecule/object actually "exists" or what "internal make-up" it has, the only thing you should ever care about is what types of interactions it can have with other particles/molecules/objects... nothing more, nothing less.
Well, the "knowing about possible types of interaction" issue kind of makes it almost mandatory to understand exactly what any entity is actually "made of", but that's a secondary issue... if you know how something behaves in any possible situation, regardless of what's inside... do you really need to know what's inside ?
Or, rather, if you know how something reacts to any imaginable interaction, would you have any actual means to determine without the shadow of a doubt "what's inside" ?
My personal answers are both negative: you don't need to know, and there's no way to know for sure.
Heh, here's the craziest thory: what if "space", "time" and "energy" don't actually exist (or worse, what if they're ALL discrete, not continuous) ?
Would we even be able to notice ? Or have we noticed that already (Planck's h) but can't grasp the concept ?
For all intents and purposes, the entire universe actually existing (on one hand) or being a completely fictional construct/simulation (on the other hand) makes no difference whatsoever.
So, basically, all what's left of reality is simply interactions between entities, not any of the entities themselves.
By reading this signature you agree to not disagree with the post you just read.
Well, people think quantum mechanics are flawed behond repair since before it come to be. Just remember that Plank after proposing that light is quantized spent most of he's career fighting that same idea.
Quantum mechanics is not intuitive, but it pass every test we make with it. It's explaining things for the best part of a cetury now*, always proposing weard things, and aways getting it right. It's hard to replace a theory that works that well.
* More than a century if you count since Plank, not Schrödinger.
Rethinking email
Yeah. Like flat screens, disc density, chip density, new chip design, photovoltaics, automobile improvements, new jets designs and so on. The military is so many light years ahead of civilian living they look like super beings, with technology barely hinting that it had evolved from ours or vise versa.
That was sarcasm.
Quantum Mechanics is the only game in town.
Epicycles was the only game in town from the 3rd century all the way through the 16th... until Copernicus came along with the correct explanation for the data and made 1300 years of scholars look like raving lunatics.
How then could Epicycle's proponents have known they were headed down a blind alley? Simple really: instead of proving it outright, each major new dataset required more refinements and additions to the theory -- Epicycles within Epicycles.
Quantum Mechanics has had nearly a century to stabilize in to a theory that each new experiment proves without needing additional refinements. Instead it has added a bazillion particles, spins, counter spins and all sorts of other oddities. It hasn't stabilized and each new addition makes the theory less likely to be correct.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
An even better example: There would be no way to build a current CPU (or even an old 8-bit 8080) without QM. The only existing computers would still be room-sized energy-hungry monsters which could be beaten by our pocket calculators. There would be no PC, no mobile phone, no mp3 player, no CD or DVD player. There would be no GPS (atomic clocks need QM, too!), no LCD screens and no LEDs.
The Tao of math: The numbers you can count are not the real numbers.
It depends if God uses Haskell or Lisp. (Yes, I know Lisp can be lazy)
Inventions have long since reached their limit, and I see no hope for further development.-- Frontinus, 1st cent. AD
When the reality is that neither is the center, and both statements are just metaphors used to create a predictive model. Just like most of science.
You could create an accurate predictive model of the universe using the metaphors of religion and the language of words if you were so inclined.
Not that anyone has.
-1 Uncomfortable Truth
Fewest holes? It has holes you could drive trucks through. The first and most important one is that it doesn't require an intelligent observer to cause a collapse of the quantum wave function. Interaction with any other matter is the only thing required for decoherence.
The case with QM is somewhat similar. The theory provides excellent results, even these inequality violations are not inconsistent with QM, just strange. Another problem with QM involves renormalization. Apparently to do the math for most of these calculations requires some very goofy steps, but again, the results agree with observations, so this oddity doesn't point the way toward a better solution.
To make a real breakthru though requires a result that is at odds with the predictions of QM. The realm where QM and/or GR break down is in the combined super heavy and super small realms... either atomic activity around black holes and/or primordial black holes. Even if someone were to come up with a competing theory to QM/GR that addressed all the issues, it wouldn't gain wide acceptance until it produced a result that both conflicted with the older theories and was confirmed by real-world evidence. (Note, I'm avoiding the phrase "experimental evidence" because in this case I want to allow the case where results to come from astronomical observations of black holes.)
Finally, I'm struck by a pair of quotes: "Not only is the universe stranger than we imagine, it's stranger than we CAN imagine." One citation is JBS Haldane and how this is at odds with Einstein "The most incomprehensible thing about the world is that it is comprehensible."
Exactly. What is observation? Don't the particles in the cat's tail observe the cat's death? The cessation of the cat's metabolic processes decreases the rate at which chemical energy is being released inside the cat and turned into heat. The amount of thermal radiation from the cat is observed by the inside of the box. The amount of thermal radiation from the box is observable by anyone outside the box, too. Vibrations from the cat breathing can affect the movement of air outside the box. Vast numbers of particles in the cat, in the box, and near the box should, through tiny interactions, register the cat's death. It is impossible for the cat's death not to be observed, if observation is merely the fact of particles having different state depending on whether the cat lived or died.
Somehow, though, uncertainties that persist in isolation are collapsed through interaction. Perhaps waveforms collapse because there is a limit to how much uncertainty they can contain, or how far that uncertainty can spread before collapsing. Perhaps there is an improbability or upper limit attached to uncertainty, just like Heisenberg's uncertainty principle places an upper bound on certainty. An observer, through interacting with an uncertain phenomenon, increases the scope of the uncertainty beyond the supportable limit.
I just realized there would be a great benefit if observation really were an anthropocentric thing. Doctors could have had Terry Schiavo observe the outcome of an experiment. If the waveform didn't collapse, then she was brain-dead. If it collapsed, then she must have been sentient to "observe" the experiment. A quantum mechanical experiment could be attached to a probe and used to test whether a woman's fetus was sentient, to decide whether she could have an abortion.
If the criterion for observation were life, rather than sentience, we could let a virus observe the experiment and finally settle that question once and for all.