This Twist on Schrödinger’s Cat Paradox Has Major Implications for Quantum Theory:
What does it feel like to be both alive and dead?
That question irked and inspired Hungarian-American physicist Eugene Wigner in the 1960s. He was frustrated by the paradoxes arising from the vagaries of quantum mechanics—the theory governing the microscopic realm that suggests, among many other counterintuitive things, that until a quantum system is observed, it does not necessarily have definite properties. Take his fellow physicist Erwin Schrödinger's famous thought experiment in which a cat is trapped in a box with poison that will be released if a radioactive atom decays. Radioactivity is a quantum process, so before the box is opened, the story goes, the atom has both decayed and not decayed, leaving the unfortunate cat in limbo—a so-called superposition between life and death. But does the cat experience being in superposition?
Wigner sharpened the paradox by imagining a (human) friend of his shut in a lab, measuring a quantum system. He argued it was absurd to say his friend exists in a superposition of having seen and not seen a decay unless and until Wigner opens the lab door. "The 'Wigner's friend' thought experiment shows that things can become very weird if the observer is also observed," says Nora Tischler, a quantum physicist at Griffith University in Brisbane, Australia.
Now Tischler and her colleagues have carried out a version of the Wigner's friend test. By combining the classic thought experiment with another quantum head-scratcher called entanglement—a phenomenon that links particles across vast distances—they have also derived a new theorem, which they claim puts the strongest constraints yet on the fundamental nature of reality. Their study, which appeared in Nature Physics on August 17, has implications for the role that consciousness might play in quantum physics—and even whether quantum theory must be replaced.
Journal Reference:
Kok-Wei Bong, Aníbal Utreras-Alarcón, Farzad Ghafari, et al. A strong no-go theorem on the Wigner’s friend paradox, Nature Physics (DOI: 10.1038/s41567-020-0990-x)
(Score: 2) by gtomorrow on Tuesday August 18 2020, @01:45PM
Nietzsche, Bartol, Burroughs, Carroll, et al are proven right!
Nothing is true. Everything is permitted.
(Score: 5, Interesting) by meustrus on Tuesday August 18 2020, @01:46PM (12 children)
I'm probably wrong here, but isn't Schrödinger's cat just a thought experiment? It's not supposed to be a thing that could literally happen, it's supposed to illustrate how superposition works with everyday objects.
The thing that we pop culture scientists always miss is that observation is destructive. The same way your eyeball casts a shadow, any measurement of a quantum state interrupts it.
We live in the same universe we're trying to observe. It's not like we're just opening up God's debug console and setting a breakpoint. Even if we were, sometimes the breakpoint itself changes the timing and you can't observe what you were trying to observe.
If there isn't at least one reference or primary source, it's not +1 Informative. Maybe the underused +1 Interesting?
(Score: 2) by rigrig on Tuesday August 18 2020, @02:04PM
As I understand it, Schrödinger wasn't happy with the idea of superposition and came up with this experiment to show how it could lead to "ridiculous" macroscopic results like a cat being both dead and alive at the same time.
No one remembers the singer.
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @02:12PM
It's not just that: Schrödinger used this specifically as a reductio ad absurdum to demonstrate what he thought must be a problem with some parts of quantum theory at the time (and to some extent to this day). The idea that a cat could be simultaneously alive and dead was intended as an example that was so patently ridiculous that there is no way it could possibly be true.
It's possible Schrödinger's argument was wrong, as some more modern interpretations do accept the possibility that cats can indeed be literally alive and dead simultaneously. However this paper might be evidence against such theories.
(Score: 2) by inertnet on Tuesday August 18 2020, @04:01PM
As I understand it, Schrödinger was right, but only for larger objects like cats and observers. It has long been demonstrated that those spooky things are true for subatomic particles.
(Score: 3, Interesting) by Anonymous Coward on Tuesday August 18 2020, @04:03PM (4 children)
The more ridiculous the claim, the more likely it is to be true, when quantum mechanics is involved.
This result is meaningful, but not quite as Earth shaking as some say. The worst part is that peddlers of woo-woo will seize on it as more "proof" that their bunkum is true.
The media reports all seem to be excited about this notion of subjectivity, but what's overlooked is that superdeterminism, nonlocality, and retrocausality also solve the problem, and most QM interpretations already incorporate, or allow for the possibility of, one of those.
Personally, I am fine with retrocausality, which isn't as upsetting as it seems when you first hear about it.
(Score: 3, Funny) by meustrus on Tuesday August 18 2020, @05:45PM (3 children)
Impressive, you took me from "you're absolutely wrong, ridiculousness is not a bellwether for truth" to "Your ideas are intriguing to me, and I wish to subscribe to your newsletter" in a mere 5 sentences.
If there isn't at least one reference or primary source, it's not +1 Informative. Maybe the underused +1 Interesting?
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @07:05PM (2 children)
The first sentence was only semi-serious, but so much of quantum mechanics (including the original Schrodinger's Cat thought experiment) was intended to disprove it, because the predictions were so ridiculous. But then they turned out to be true.
I don't have a newsletter, but Sabine Hossenfelder [blogspot.com] does. She prefers superdeterminism [frontiersin.org] (and I think Einstein would as well, were he still alive).
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @09:21PM (1 child)
Ah. Her YouTube channel pops up in my recommendations. I haven't clicked on it because (besides having lots of other stuff I want to watch), it wasn't clear which side of the kook line she fell. As you mentioned, there is no shortage of bunkum peddlers peddling in QM topics. It feels like the 70's all over again!
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @10:37PM
She's a contrarian, but definitely not a kook.
(Score: 2) by sjames on Tuesday August 18 2020, @06:21PM (1 child)
My God, it's full of Heisenbugs!
(Score: 2) by Gaaark on Tuesday August 18 2020, @07:16PM
and it's breaking bad!
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 1) by khallow on Wednesday August 19 2020, @02:56AM
Thought experiments aren't just thought experiments. They may be extremely difficult to do even with technology far more advanced than our own, but they are possible.
Here, we already have a number of proven technologies for blowing up quantum level effects to macroscopic effects. Shutting a person into near perfect quantum sequestration (for an adequate period of time) is impossible with our present technology, but feasible. Eventually someone will do it.
Only for the observer! In the Wigner's Friend example, the observer isolated in the lab makes the observation, but to the outside world, that observation is entangled with the state that the Friend is attempting to observe. The collapse doesn't happen until the outside world observes either the Friend's state or the state of the particle that the Friend was observing (and entangled with).
(Score: 2) by FatPhil on Wednesday August 19 2020, @03:43PM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by SomeGuy on Tuesday August 18 2020, @07:48PM
I'll tell you what it feels like. It sucks. It sucks big fat hairy unobserved balls. That is what it is like.
(Score: 2, Touché) by Anonymous Coward on Tuesday August 18 2020, @08:01PM (10 children)
And it's all completely bullshit. Collapsing the wave function based on an observer is crap. There's nothing special about an observer. To say the wave function doesn't collapse until it is observed by a human brain implies that the human brain is something outside of space time. Which it isn't. The whole concept of "observer" being something other than part of the same matter that's being observed is wrong. Everything about this thought experiment is wrong. It's not how any of this works nor could it ever be. It's bullshit.
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @09:45PM
So . . . you think there's a slim chance it is correct?
(Score: 1, Insightful) by Anonymous Coward on Tuesday August 18 2020, @10:53PM (1 child)
This isn't a thought experiment, it's a real experiment. So, like it or not, you are stuck with it. Welcome to quantum mechanics.
Very few real scientists still hold the belief that consciousness is involved in wavefunction collapse. There is still a problem with the exact definition of "measurement," (and it would have been better if they had always said "measurement" and not "observer") but it doesn't have anything to do with consciousness.
(Score: 2) by FatPhil on Wednesday August 19 2020, @03:53PM
"it doesn't have anything to do with consciousness."
is directly contradicted by the summary's:
"Their study, which appeared in Nature Physics on August 17, has implications for the role that consciousness might play in quantum physics".
I'm perfectly happy to offload blame for this onto SciAm, which has been bollocks science journalism for decades, as I've not read TFP. The public are the victims of poor science journalism, so the blame and ire for the conflation and mangling of concepts should be directed as high up the chain as possible. Almost certainly SciAm, don't be hard on AC.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by acid andy on Wednesday August 19 2020, @12:46AM
But the brain doesn't really observe without a mind to experience the observation, does it?
If a cat has kittens, does a rat have rittens, a bat bittens and a mat mittens?
(Score: 1) by khallow on Wednesday August 19 2020, @03:08AM (5 children)
Yet it happens. We have wave collapses and we have observers observing these collapses. Nowhere else in the system, do we have a mechanism for causing wave collapse. For example, a pure quantum model is reversible with no disentanglement happening at all.
I have to say, contrary to assertion, that the characteristics of the observer, you, is indeed fundamental to how you see the universe.
(Score: 2) by FatPhil on Wednesday August 19 2020, @04:06PM (4 children)
Not everyone assumes we have wavefunction collapse, you need to understand that you have chosen a particular interpretation of QM that includes it, and nobody knows whether you are right or wrong to so do. The discussion of "what is a measurement/observer" remains in the realm of philosophy not science presently, although if i'm interpretting the absrtact correctly, and this paper delivers what it promises, we are heading towards testable claims that will reveal properties of measurement that could decide the truth of the measurement postulate. (I'm obviously Popperist - not falsifiable implies not science.)
Of course, all of these things aren't "the laws of physics" or "reality", they are mathematical tools that are currently the most useful for predicting how reality seems to behave, and one shouldn't forget that either.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 1) by khallow on Wednesday August 19 2020, @11:05PM (3 children)
From observation, we do indeed have wavefunction collapse and it can get quite crazy [wikipedia.org]. The two slit experiment [wikipedia.org] is a standard example as well. This is model-independent.
(Score: 2) by FatPhil on Thursday August 20 2020, @02:34PM (2 children)
Nonsense. Bohm and many-worlds interpretations don't rely on the concept existing at all. Even the Copenhageners were keen to stress that the concept was a mathematical model, and not necessarily anything "real".
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 1) by khallow on Thursday August 20 2020, @11:40PM (1 child)
That's the thing about observations. They exist even if your models don't rely on them - or even predict that they shouldn't exist.
(Score: 2) by maxwell demon on Saturday August 22 2020, @08:20PM
Every interpretation explains all observations, including those interpretations that have no wave function collapse. Therefore it is not true that we have observed a wave function collapse. What we've observed is phenomena which some, but not all, interpretations explain with a wave function collapse. Indeed, in some interpretations the wave function isn't even physical, which means that in those it is even conceptionally impossible to observe its collapse.
The Tao of math: The numbers you can count are not the real numbers.
(Score: -1, Spam) by Anonymous Coward on Tuesday August 18 2020, @10:00PM
Marissa Van Eck FAKENAME NIGGER CUNT Azuma Hazuki: So "that was NOT me posting" https://soylentnews.org/comments.pl?noupdate=1&sid=37033&page=1&cid=985641#commentwrap [soylentnews.org] which YES, you said when you LIBELED me publicly BEFORE it with YOU saying "So that's a "yes" to schizophrenia/schizoaffective disorder and a "no" to "am taking meds for said disorder" LIBELING ME then...?" per YOUR https://soylentnews.org/comments.pl?noupdate=1&sid=37033&page=1&cid=982854#commentwrap [soylentnews.org] you stupid pitiful FAKENAME fuck online LIAR piece of fucking SHIT NIGGER?
OR
Was it when I GOT YOUR REAL NAME & found you are a satanist/anti-god HERE https://redeeminggod.com/sermons/luke/luke_7_36-50/#comment-269796 [redeeminggod.com] also which most ALL you "LEFTIST" LOSER weirdos usually are (which YES, in THIS other exchange "Why do you assume that you finding discussion threads on other sites with me in them will scare me?" quoted from https://soylentnews.org/comments.pl?noupdate=1&sid=38720&page=1&cid=1028402#commentwrap [soylentnews.org] you DID admit FINALLY to saying it was you - ESPECIALLY AFTER dozens of doctors RECENTLY seconded me on Hydroxychloroquin + Zinc (& Vitamin D3 imo along w/ other things I noted that are anti-viral + antibacterial like RAW GARLIC too)).
Do me a favor - DENY ANY OF THOSE, please & I will continue PROVING YOU ARE A NIGGER SHITBAG LOSER, devil... as I already DID here https://soylentnews.org/comments.pl?noupdate=1&sid=38720&page=1&cid=1028211#commentwrap [soylentnews.org]
The TRUE BEAUTY of SATANIST FUCKS like YOU (antigod assholes)? TRUTH & FACT DESTROYS LIBELOUS DEVILS LIKE YOU - just like I did you & OTHER AHOLES who doubted what I wrote on what is NOW PROVEN TRUE by DOCTORS, admitted in mainstream media etc. (as I showed in those links' exchanges above easily) & especially LATELY by DOZENS of doctors (I have proof from pros - NOT LIBEL like you did to me PUBLICLY & I can still FRY YOU FOR IT FUCKER, live in fear fuck) MINUS any psych pros backing you.
SAY 1 THING, YOU STINKING LIBELOUS NIGGER FUCK & I will CONTINUE LEVELLING YOU PUBLICLY with facts - not libel as you tried on me, stupid "Marissa von DUMBO", lol - please, say 1 thing & the BEATING on you, PUBLICLY will continue in this thread where you will have a HELL of a TIME "downmod burying it" via downmod brigades doubtless ONLY yourself via multiple sockpuppet accounts etc. (downodding to HIDE it? FORGET IT vs. me - everyone sees you @ it now, lol - thanks, just as I SAID "your kind", demonic SWINE/antigod LOSERS, always do).
WHY SHOULD YOU FEAR LIBELING ME PROJECTING IT NOW, TRYING TO HIDE IT TOO?
TOUGH HIDING YOU LIED about LIBELING ME, especially via INHERENTLY DAMAGING STATEMENTS libeling me as you did see GOLDWATER RULE below too fuckface CUNT you are (wikipedia proof https://soylentnews.org/comments.pl?noupdate=1&sid=37033&page=1&cid=985366#commentwrap [soylentnews.org] & you said "No jury or judge would back it" here https://soylentnews.org/comments.pl?noupdate=1&sid=37033&page=1&cid=985353#commentwrap? [soylentnews.org] Ok - like I said earlier here which you TRIED TO DOWNMOD HIDE as I knew you HAVE to (everyone sees it anyhow) - TRY ME FUCKER - say 1 thing you COWARDLY STUPID LITTLE FUCK & we'll SEE what happens to you, fuckface CUNT you are).
As I said "DO YOU WANT TO BE SUED" for breaking the GOLDWATER RULE? See here again https://soylentnews.org/comments.pl?noupdate=1&sid=37033&page=1&cid=985329#commentwrap [soylentnews.org] for YOUR (& everyone else's) reference of YOUR LIBEL of myself
APK
P.S.=> Oh, I am going to have a FIELDDAY on YOUR ASS fucker - catching you not ONLY IN LIES above, but also in the fact you are a GODLESS fucking LOSER - come on, say something, question the above where you LIED fucker ("it was not me saying it" but it WAS in those links calling me a nutcase essentially when YOU SAID YOU DID NOT (because it IS grounds for SUING THE LIFE OUT OF YOUR WORTHLESS ASS because your statements are NOT BACKED BY actual psychiatric pros in professional psychiatric grounds LIBELING ME)) - oh, you are NEVER going to LIVE THIS DOWN & believe you me - I am going to MAKE SURE you don't - live with your HUMILIATION loser... apk
(Score: 0) by Anonymous Coward on Tuesday August 18 2020, @11:46PM
Some of these comments in this discussion of Schrödinger's Cat remind me of the story of "msscribe" who was both real and not real at the same time. You can go and search it up, there's an amazingly in-depth discussion of the history of "msscribe" on YouTube, but the essence of the story is a person who craved online attention created a fake persona "msscribe" and then created a bunch of other fake sock-puppet accounts which verbally attacked and threatened to sue the "msscribe" account as a way of stirring up controversy and gaining notoriety.
If I were the moderators of Soylent News, I'd be banning every IP address and account associated with any and all posts that may or may not be libellous, whether or not there's only one person or more than one person behind them all, as a way to pour cold water on the whole situation and make it clear that Soylent News is not their personal stage. There are a whole lot of crazies on the internet, and you don't want to encourage any of them to think of this place as their private playground.