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Related: About this forumQuantum Physics May Be Even Spookier Than You Think
https://www.scientificamerican.com/article/quantum-physics-may-be-even-spookier-than-you-think/It is the central question in quantum mechanics, and no one knows the answer: What really happens in a superpositionthe peculiar circumstance in which particles seem to be in two or more places or states at once? Now, in a forthcoming paper a team of researchers in Israel and Japan has proposed an experiment that could finally let us say something for sure about the nature of this puzzling phenomenon.
Their experiment, which the researchers say could be carried out within a few months, should enable scientists to sneak a glance at where an objectin this case a particle of light, called a photonactually resides when it is placed in a superposition. And the researchers predict the answer will be even stranger and more shocking than two places at once.
The classic example of a superposition involves firing photons at two parallel slits in a barrier. One fundamental aspect of quantum mechanics is that tiny particles can behave like waves, so that those passing through one slit interfere with those going through the other, their wavy ripples either boosting or canceling one another to create a characteristic pattern on a detector screen. The odd thing, though, is this interference occurs even if only one particle is fired at a time. The particle seems somehow to pass through both slits at once, interfering with itself. Thats a superposition. And it gets weirder: Measuring which slit such a particle goes through will invariably indicate it only goes through onebut then the wavelike interference (the quantumness, if you will) vanishes. The very act of measurement seems to collapse the superposition. We know something fishy is going on in a superposition, says physicist Avshalom Elitzur of the Israeli Institute for Advanced Research. But youre not allowed to measure it. This is what makes quantum mechanics so diabolical.
For decades researchers have stalled at this apparent impasse. They cannot say exactly what a superposition is without looking at it; but if they try to look at it, it disappears. One potential solutiondeveloped by Elitzurs former mentor, Israeli physicist Yakir Aharonov, now at Chapman University, and his collaboratorssuggests a way to deduce something about quantum particles before measuring them. Aharonovs approach is called the two-state-vector formalism (TSVF) of quantum mechanics, and postulates quantum events are in some sense determined by quantum states not just in the pastbut also in the future. That is, the TSVF assumes quantum mechanics works the same way both forward and backward in time. From this perspective, causes can seem to propagate backward in time, occurring after their effects.
matt819
(10,749 posts)The problem is that without understanding the remaining 10% it's about as useful and informative as reading this passage in Latin.
I mean, really, do people understand this? And are these people humans or aliens?
DRoseDARs
(6,810 posts)VMA131Marine
(4,159 posts)It's not an either-or proposition.
FiveGoodMen
(20,018 posts)VMA131Marine
(4,159 posts)longship
(40,416 posts)byronius
(7,410 posts)Clearly consciousness is a Thing. Observation changes particle state.
Almost makes you think particle consciousness is a Thing.
Plus, those gravity waves sent back in time...
Spooky indeed.
SCantiGOP
(13,878 posts)certainly applies here: the universe is not just stranger than you imagine, it is stranger than you CAN imagine.
hunter
(38,349 posts)Whatever it is, time is not some peculiar "fourth dimension" imposed on a three dimensional Cartesian universe.
I pay some attention to the Transactional Interpretation of Quantum Mechanics (TIQM).
John G. Cramer has written plenty about it, and most is available on the internet, some accessible to readers without heavyweight math or science backrounds.
https://www.npl.washington.edu/AV/#2
TIQM clears out some of the "spookinesss" often attributed to quantum mechanics, especially by people who are looking for mysteries where none exist. TIQM is some weird stuff, just as all things in quantum physics are, but it works without any claims that human consciousness, or any consciousness at all -- god, dog, or space alien -- magically influences quantum interactions.
Shit doesn't happen in the quantum world just because we supposedly special humans are watching or not watching. Curious quantum interactions we humans set up on a lab bench happen randomly in nature without any conscious observer.