from the I-hope-he-has-enough-cats-for-future-experiments dept.
Submitted via IRC for SoyCow9088
2,000 "Schrodinger's Cats" break record for large-scale quantum superposition
The world of quantum mechanics, where particles can be in two places at once or entangled with each other across vast distances, sounds spooky to us living in the macroscopic world of classical physics. But where exactly the boundary between the two lies is still a mystery. Now physicists have blurred the line more than ever before, with a new experiment showing that massive molecules containing up to 2,000 atoms can exist in two places simultaneously.
The discovery was made using an advanced version of an experiment that's been conducted countless times over the last 200 years – the double slit experiment. It was through this experiment that scientists came to understand the duality of light as both particles and waves.
The experiment sounds fairly simple. Light is beamed towards a surface that has two slits cut into it, and another surface behind it that the light ends up projected onto. If light was made up of only conventional particles, then the pattern on the rear surface would just appear in the shape and size of the slits. But waves of light bounce off each other like ripples in water, creating a kind of tiger-stripe pattern on the surface.
But the strangest thing is that even when the experiment is done with individual photons (or particles of light), the same striped pattern appears. Somehow, these photons don't seem to be taking just one path as they might be expected to, but are traversing all of them at once and interfering with themselves.
This phenomenon is known as quantum superposition, and it's most famously illustrated by Schrödinger's Cat. In this thought experiment, a cat hidden in a box is neither alive nor dead, but exists as both at the same time. When the box is opened, this superposition collapses into one state or the other.
By the same token, it's been said that if detectors were set up at the slits, so they were measuring which path the light was taking, the striped patterns would disappear. The fuzziness of the outcome clears up as soon as it's measured.
But superposition only seems to apply in the quantum realm – as objects get bigger, it gets harder for this phenomenon to occur, and by the time you get up to the macroscopic scale it seems to disappear entirely. Even Schrödinger's Cat needs a quantum link – the story often goes that there's a radioactive atom in the box too, and the cat's survival hinges on whether the atom decays or not.
The research was published in the journal Nature Physics.
(Score: 4, Funny) by The Mighty Buzzard on Sunday October 06 2019, @02:17PM
That's gotta be one big fucking litter box.
My rights don't end where your fear begins.
(Score: 2) by Rupert Pupnick on Sunday October 06 2019, @03:51PM (6 children)
One of you QM experts out there can correct me if I’m wrong, but this is 100% expected experimental behavior that is in part a consequence of the idea of wave-particle duality. It’s being done on a scale involving more massive particles than ever before, but it’s nothing new.
If there’s a future application or new theory being pursued here, I can’t find it in TFA.
(Score: 2) by c0lo on Sunday October 06 2019, @06:28PM (4 children)
Now, I wonder if they fire Rupert Pupnick through two doors, repeatedly, will the splats on the opposite wall show interference pattern?
If not, where's the limit when enough atoms start to act as a particle and not as a wave packet?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Rupert Pupnick on Sunday October 06 2019, @09:56PM (3 children)
I’m not volunteering to be a test subject or anything, but given that I weigh about 180 lbs, I bet you maxwells demon could give you all the necessary parameters like slit spacing and size to run the test to find out.
(Score: 2) by c0lo on Monday October 07 2019, @01:24AM (2 children)
Yeah, well, it's a bet. Some, especially scientists, try as hard as possible to avoid betting...
... so don't hold against them if they organize experiments using Rupert Pupnicks to validate what that maxwells daemon could give.
But... mmmm... you may be safe, unless you diet yourself down to a weight of 21.76470 μg (the Plank mass) [wikipedia.org]. But again, you never know what those scientists may try:
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Rupert Pupnick on Monday October 07 2019, @01:04PM (1 child)
Planck Mass! Why didn't you (or someone else, like an author of a referenced article) say so sooner? It's very helpful in putting things in perspective, thanks.
According to the Nature Journal article, the test molecules have a mass of over 25000 Da which I calculate to be about 4 x 10^-26 g. That's more than 20 orders of magnitude smaller than the Planck Mass of about 2 x 10^-5. Seems like they've got a ways to go before they can expect that limitation to affect the experiment.
As to scientists and bets, well it seems to me scientists make bets all the time, but usually with other people's money in the form of grants. The question is how good are the bets in terms of expected value of return versus the money going in.
(Score: 2) by c0lo on Monday October 07 2019, @01:49PM
Hey, ho! Don't be that dismissive. The current experimental conditions still deal with wavelengths of femtometers - that's 5 orders lower than the typical size of atoms, in the magnitude range of proton sizes.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by maxwell demon on Sunday October 06 2019, @09:18PM
Assuming Quantum mechanics is still valid at that size, this is indeed the expected behaviour. But we didn't know for sure that it is before we tried it.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @04:07PM (12 children)
just a throw back to aristoteles whistling which makes him a locomotive:
"But the strangest thing is that even when the experiment is done with individual photons (or particles of light), the same striped pattern appears. Somehow, these photons don't seem to be taking just one path as they might be expected to, but are traversing all of them at once and interfering with themselves."
one could also argue, logically, that the premise is wrong: the experiment fails because the photons are NOT individual. one could argue, that the result of the double slit experiment IS the proof that no individual (single?) photons where emitted.
logically sound, but probably, there's another experiment that proofs that the source is indeed emitting single or individual photons?
(Score: 2) by Runaway1956 on Sunday October 06 2019, @04:33PM (5 children)
Might it be safe to say that the observations are flawed, because the observers are flawed? Nothing wrong with the experiment, or the results of the experiment. The problem is the experimenter's flawed understanding.
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @04:38PM (4 children)
Did you read the original paper or are you just flapping your mouth as usual?
--
We need to eat the babies! - some conservative at an AOC townhall meeting
(Score: 2) by Runaway1956 on Sunday October 06 2019, @04:55PM (3 children)
I didn't pay the nine bucks to read the original paper, no. Nor am I flapping my gums. I am instead typing on a keyboard, almost hoping to trigger some poor fool. Are you that poor fool?
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @05:15PM (2 children)
No. If you are looking for a poor fool I suggest you look in your mirror.
--
We need to eat the babies! - some conservative at an AOC townhall meeting
(Score: 1, Offtopic) by Runaway1956 on Sunday October 06 2019, @05:23PM (1 child)
Vampires don't do mirrors.
(Score: 0) by Anonymous Coward on Monday October 07 2019, @12:13AM
Thus Vampires are neither particles nor waves.
(Score: 2) by Rupert Pupnick on Sunday October 06 2019, @05:10PM (5 children)
Yes, there is the experiment using photo detectors that show photons as discrete packets of energy that arrive at discrete times.
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @07:56PM
wooosh!
summary is idiotic. the big deal with the double slit experiment is that it works the same with electrons as with light, not that it works with light.
the "double slit experiment with light" was well known in the 1800s, and the "weird" light effect was the later photo-electric effect.
(Score: 4, Informative) by maxwell demon on Sunday October 06 2019, @09:26PM (3 children)
Actually the experiment that ultimately proved photons having particle properties was the Compton scattering experiment, which showed that photons bounce from electrons the way particles do.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0) by Anonymous Coward on Monday October 07 2019, @10:49AM (2 children)
you mean photo-electric effect, which showed that to push electrons off a chunk of material the frequency of light is important, not its intensity.
(Score: 0) by Anonymous Coward on Monday October 07 2019, @03:10PM
yeah, you gotta find the "right sized" bag of electrons when you want to ionize some atoms at home.
beware the doddgy electrons they harvest "overseas" which come from over fertilized and not cared-for atoms; half of 'em don't pack the "UMPHf" required to cascade the electrons of at home so netxt time you go to homedepot or whatnot to buy your bag of electrons, be sure to get those sourced locally ...
(Score: 2) by maxwell demon on Monday October 07 2019, @04:26PM
No, I mean the Compton effect. The photoelectric effect was what led Einstein to postulate the particle nature of light, but only the Compton effect did remove all doubts about it.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 4, Interesting) by c0lo on Sunday October 06 2019, @06:20PM
TFS stops exactly before the announcement for what was experimented begins
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @07:20PM (1 child)
What sort of idiot scientists think that they can get away with killing 2,000 cats just to scale up an experiment that's already been done?
(Score: 3, Funny) by Anonymous Coward on Sunday October 06 2019, @07:23PM
Chinese scientists, just before the annual faculty BBQ?
(Score: 0) by Anonymous Coward on Sunday October 06 2019, @09:11PM (4 children)
Has anyone actually checked this?
(Score: 2) by c0lo on Sunday October 06 2019, @09:27PM
A photon detector at the quantum scale is equivalent with a photon absorbing obstacle.
Got the answer to your question yet?
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by maxwell demon on Sunday October 06 2019, @09:35PM (2 children)
Yes.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Zinho on Monday October 07 2019, @01:06AM (1 child)
I looked into that experiment a while back, and found out that the "detector" they used was a pair of polarizers oriented at right angles to each other. That seemed like cheating to me; it's not detecting which slit was used as much as ensuring that the photon only passes through one. Which is basically the same as only having one slit.
Is there a different experimental setup you know about (and can describe to us) that detects which slit was used without somehow shuttering the other?
"Space Exploration is not endless circles in low earth orbit." -Buzz Aldrin
(Score: 2) by maxwell demon on Monday October 07 2019, @04:34AM
Look at delayed choice experiments.
The Tao of math: The numbers you can count are not the real numbers.