Physicists Made a Flying Army of Laser 'Schrodinger's Cats' (livescience.com)

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Physicists Made a Flying Army of Laser 'Schrodinger's Cats' (livescience.com)

Posted by EditorDavid on Saturday February 2, 2019 @05:34AM from the dead-or-alive dept.

PolygamousRanchKid quotes LiveScience: A laser pulse bounced off a rubidium atom and entered the quantum world -- taking on the weird physics of "Schrodinger's cat." The laser pulses didn't grow whiskers or paws. But they became like the famous quantum-physics thought experiment Schrodinger's cat in an important way: They were large objects that acted like the simultaneously dead-and-alive creatures of subatomic physics -- existing in a limbo between two simultaneous, contradictory states.

"In our experiment, the [laser cat] was sent to the detector immediately, so it was destroyed right after its creation," said Bastian Hacker, a researcher at the Max Planck Institute of Quantum Optics in Germany, who worked on the experiment. But it didn't have to be that way, Hacker told Live Science. "An optical state can live forever. So if we had sent the pulse out into the night sky, it could live for billions of years in its [cat-like] state." That longevity is part of what makes these pulses so useful, he added. A long-lived laser cat can survive long-term travel through an optical fiber, making it a good unit of information for a network of quantum computers... In the new experiment, described in a paper published Jan. 14 in the journal Nature Photonics, researchers created laser pulses that are in superposition between two possible quantum states. They called the little pulses "flying optical cat states...."

"Cat states can encode quantum information in a way that allows [us] to detect optical loss and correct for it. Although every optical transmission has losses, the information can be transmitted perfectly."

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yeah by slashpot · 2019-02-02 05:44 · Score: 0

ok, wtf does this mean?
1. Re:yeah by HiThere · 2019-02-02 07:06 · Score: 1
  
  One thing it means (claims...not really tested, but certainly made plausible) is that quantum uncertainty can persist in ways that are macroscopically significant.
  To me this is an argument in favor of the EWG multiworld interpretation of quantum physics, but I'm no expert, and others may well see this as an argument in favor of some other interpretation. That I can't see this as favoring the Copenhagen interpretation doesn't mean that someone else can't.
  OTOH, one needs to remember that an interpretation is just that, and doesn't in and of itself predict any particular physical realization. This is therefore either consistent with all the existing interpretations (I think it is), or it's inconsistent with all of them. But to me long term stable uncertain states argue against the Copenhagen interpretation. (But, that said, I don't like that interpretation anyway, so I'm biased.)
  P.S.: To answer your question more directly, it makes quantum computing at scale much more plausible.
  
  --
  
  I think we've pushed this "anyone can grow up to be president" thing too far.
2. Re: yeah by Anonymous Coward · 2019-02-02 07:16 · Score: 0
  
  Well, you may find that an interpretation, which is in fact just an interpretation, may be the correct interpretation later in time when a differing interpretation is mocked viciously. I suppose the rule would be everyone has an opinion and some of those opinions are definitely wrong.
3. Re: yeah by Mattcelt · 2019-02-02 07:34 · Score: 4, Funny
  
  I prefer to think that both the Copenhagen and Many-worlds interpretations are correct.
  ...until one of them is observed.
4. Re: yeah by Anonymous Coward · 2019-02-02 07:46 · Score: 0
  
  All I know is the conservation of energy principle is definitely correct no matter what hipsters say in coffee shops. There is no such thing as a free lunch, for those of you who went to public school
5. Re:yeah by careysub · 2019-02-02 08:10 · Score: 1
  
  All I can say is that "Flying Army of Laser 'Schrodinger's Cats" sure sounds cool!
  Maybe they can take on the Sharknado.
  
  --
  Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
6. Re:yeah by Tough+Love · 2019-02-02 12:20 · Score: 1
  
  one needs to remember that an interpretation is just that, and doesn't in and of itself predict any particular physical realization.
  Superposition isn't an interpretation, it's an experimentally verified fact of nature.
  
  --
  When all you have is a hammer, every problem starts to look like a thumb.
7. Re:yeah by Anonymous Coward · 2019-02-02 13:33 · Score: 0
  
  They're going to completely kick the asses of the non-quantum sharks with lasers.
8. Re: yeah by Anonymous Coward · 2019-02-02 22:59 · Score: 0
  
  It means that the pet store was out of sharks with friggin lasers
9. Re:yeah by HiThere · 2019-02-03 06:05 · Score: 2
  
  But what does it mean? How do you interpret it?
  Every interpretation of quantum physics predicts the same experimental results, but the interpretation of them is less clear. And the English translation of the math differs wildly depending on which interpretation you use.
  
  --
  
  I think we've pushed this "anyone can grow up to be president" thing too far.
Can someone please explain. by xonen · 2019-02-02 05:44 · Score: 1

I read the article, and still don't understand a thing. I think it is not because i am so stupid, but because the article has been so dumbed down that it no longer contains any useful information. So, if someone please can explain what this is about, without using a cat or car analogy, please feel free to do so.

--
A glitch a day keeps the bugs away.
1. Re:Can someone please explain. by ceoyoyo · 2019-02-02 05:56 · Score: 1
  
  The summary made my head hurt. The article made me dumber.
  As far as I can tell, they bounced a few (up to four) photons off a specially prepared rubidium atom and demonstrated that those photons were in a state of superposition... maybe the same state? They speculate that this might be useful for quantum networking because if you can send four photons instead of one, you've got a better chance of receiving some on the other end.
  They make a big deal about the four photons being like Schrödinger's cat, a macroscopic object in a state of quantum superposition. At the end of the article they admit that four photons aren't really a macroscopic object anything like a cat.
2. Re:Can someone please explain. by Anonymous Coward · 2019-02-02 06:05 · Score: 1
  
  If the physicists involved in the experiment actually described anything as "flying optical cat states" then they, and their lab, should be burned to the ground, with the 'journalist' inside.
  Maybe that would prevent the stupidity infection from spreading any further.
3. Re:Can someone please explain. by Anonymous Coward · 2019-02-02 06:09 · Score: 0
  
  to dumb it down even further
  shoot light at open space... light lives on "supposedly" forever.
  shoot light at wall, light is stopped by wall...
4. Re:Can someone please explain. by Fly+Swatter · 2019-02-02 06:22 · Score: 1
  
  If you send four of the same info that might not get there, how would you know that someone didn't intercept one and let the rest pass by? Whoops, that would circumvent the basic security promise of the quantum entanglement theory.
5. Re: Can someone please explain. by Anonymous Coward · 2019-02-02 06:26 · Score: 0
  
  Oh stop. That is an easy process to verify. Anyone can get reproducible examples in a quality lab. And quality labs are a lot rarer than you might think, at least in terms of which standards they adhere to.
6. Re:Can someone please explain. by Fly+Swatter · 2019-02-02 06:31 · Score: 1
  
  What happens when it hits a prism?
7. Re: Can someone please explain. by Anonymous Coward · 2019-02-02 06:47 · Score: 0
  
  Depends on the prism I guess
8. Re:Can someone please explain. by Anonymous Coward · 2019-02-02 06:52 · Score: 0
  
  The premise is, in quantum physics, that when the photon hits the rubidium atom it interacts with a super position of all three states( two "ground" states or one "excited" state.) When they measured the photon it's phase became non-deterministic, due to it's entanglement with the rubidium atom. One way to imagine it, is you could say the photon hit the detector and was destroyed and is flying into outer space at the same time, both may be equally or partially true.
9. Re: Can someone please explain. by Anonymous Coward · 2019-02-02 06:56 · Score: 0
  
  Nice try. Super positioning does not include being in multiple places at the same time. That is something else entirely. Geez.
10. Re:Can someone please explain. by ceoyoyo · 2019-02-02 07:09 · Score: 1
  
  Yes, that seems like a potential issue. I get the feeling that these guys did something cool with quantum optics and then added "and yeah, it could be useful for, um, encryption!"
  I get the feeling quantum encryption generally is a way optics geeks have figured out how to get governments to give them money without having to build laser weapons though.
11. Re:Can someone please explain. by HiThere · 2019-02-02 07:10 · Score: 1
  
  Somehow it always seems to be the case that "theoretical promises of secure communication are always broken by the actual implementation". So this shouldn't be a surprise. Merely unwelcome.
  
  --
  
  I think we've pushed this "anyone can grow up to be president" thing too far.
12. Re:Can someone please explain. by novakyu · 2019-02-02 07:40 · Score: 5, Informative
  
  Try this. This is the actual article (in a reputable journal, no less) that was swallowed to make that pile of shit that is TFA.
13. Re: Can someone please explain. by Anonymous Coward · 2019-02-02 10:26 · Score: 0
  
  Ask Donald Trump, he's prism bound for sure.
14. Re:Can someone please explain. by Tough+Love · 2019-02-02 11:35 · Score: 1
  
  Miraculously, the original Nature article isn't paywalled: https://www.nature.com/article...
  
  --
  When all you have is a hammer, every problem starts to look like a thumb.
15. Re:Can someone please explain. by Tough+Love · 2019-02-02 11:45 · Score: 2
  
  If the physicists involved in the experiment actually described anything as "flying optical cat states" then they, and their lab, should be burned to the ground, with the 'journalist' inside.
  They do in fact use that phase, here in context: "We then employ the entanglement to control the flying optical cat state by means of a coherent rotation and subsequent measurement of the atomic spin direction." But don't get out your torch and pitchfork just yet, it seems that cat state is actually accepted terminology.
  
  --
  When all you have is a hammer, every problem starts to look like a thumb.
16. Re:Can someone please explain. by Tough+Love · 2019-02-02 11:58 · Score: 1
  
  On a quick scan and with my limited knowledge of the field, it seems that they verify the photons are in superposition by virtual of conforming to quantum as opposed to classical statistics. They don't attempt to transmit information via individual photons.
  
  --
  When all you have is a hammer, every problem starts to look like a thumb.
17. Re:Can someone please explain. by SlaveToTheGrind · 2019-02-02 12:59 · Score: 1
  
  Folks must have modded you up before noticing that your link is paywalled. $8.99 for a 48 hour "rental" would make Blockbuster jealous.
18. Re:Can someone please explain. by postbigbang · 2019-02-02 14:20 · Score: 1
  
  So we listen for radio signals for alien communications. We have huge dish arrays, radio-silent areas, all in a quest to listen for alien music.
  We should be watching for entangled photonic emissions instead? Should we be sending entangled photons at a signal that might be detected?
  We should learn to listen to the flying optical cat states, silly as that sounds. At some point, their very presence says there's intelligence, as this isn't a natural state of the universe.
  
  --
  ---- Teach Peace. It's Cheaper Than War.
19. Re:Can someone please explain. by dgatwood · 2019-02-02 16:35 · Score: 1
  
  What happens when it hits a prism?
  No idea, but when you shoot it at a Prizm, the driver gets out and yells at you.
  
  --
  Check out my sci-fi/humor trilogy at PatriotsBooks.
20. Re:Can someone please explain. by novakyu · 2019-02-03 11:24 · Score: 2
  
  Yeah, here's a preprint link. I was actually fooled myself, because the first page looked fine. Sneaky bastards. (I mean, I can get the full article from the publisher's site through my library subscription, but that's beside the point.)
21. Re:Can someone please explain. by Pseudonym · 2019-02-03 13:00 · Score: 1
  
  What part of "flying army of laser cats" didn't you understand?
  
  --
  sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
So they sent laser 'info' in an unknown state. by Fly+Swatter · 2019-02-02 06:16 · Score: 1

How does this help anything, in practical terms? I mean if you don't know what is was you sent, how does it help to know what it was when someone gets it? If you mention the word entanglement I will hit you in the eye with a bazzillion photons of 'unknown' state.
1. Re:So they sent laser 'info' in an unknown state. by HiThere · 2019-02-02 07:13 · Score: 1
  
  Well, it's a preliminary lab result, so it doesn't promise anything directly. But it indicates that quantum states can be maintained indefinitely, and this has strong relationship to scaling quantum computing. I'm rather sure, however, that any quantum computer would use a different source of entanglement.
  
  --
  
  I think we've pushed this "anyone can grow up to be president" thing too far.
Thought experiment ends thought by Kohath · 2019-02-02 06:31 · Score: 2

The cat has jumped the shark.
1. Re:Thought experiment ends thought by Anonymous Coward · 2019-02-02 20:56 · Score: 0
  
  Schrodinger is rolling in his grave...
  or not.
Question by PPH · 2019-02-02 06:38 · Score: 2

In what state is the obligatory cat chasing this laser beam?

--
Have gnu, will travel.
1. Re: Question by Anonymous Coward · 2019-02-02 06:44 · Score: 0
  
  Did you not just read the article? A cat can exist in more than one state or none at all. I bet there will be cliffs notes for the easily bored
Nothing really new here by Anonymous Coward · 2019-02-02 06:43 · Score: 0

Superpositions of states have been known about and created in labs etc for a long time. This is just someone attempting to sell out on the woo-woo part of what is, in essence, a routine application of QM. Sure, the technical skill to make it happen here might be new, but the whole "Schroedinger's Cat" part is complete PR fluff. Shame on the submitter and editor for letting in through.
The laser pulses didn't grow whiskers or paws by Anonymous Coward · 2019-02-02 06:50 · Score: 0

Oh really. Really? REALLY!? it did not grow whiskers or paws!?
What, ffs. are you thinking writing this?
How is this good for quantum computers? by magusxxx · 2019-02-02 07:13 · Score: 2

If it's a cat then won't it just ignore you when you want something from it?

--
Care killed the cat, but satisfaction brought it back.
That's nothing... by LordHighExecutioner · 2019-02-02 07:46 · Score: 1

Schwarzschild's cats are much more interesting...
What? by Anonymous Coward · 2019-02-02 07:46 · Score: 0

Well, sure, but...what?
Cats by jargonburn · 2019-02-02 09:22 · Score: 1

God damn. Someone is seriously desperate have others think they understand what is happening here. REALLY pushing the whole "cat" thing. My eyes glazed over at "[laser cat]". Honestly, this just felt...dumb. Also, while the article may specifically discuss it (didn't bother reading it), I feel the summary could have gone ahead and hyperlinked Schrödinger's cat to something like Wikipedia or whatever.
1. Re:Cats by Tough+Love · 2019-02-02 12:13 · Score: 1
  
  The livescience article is dumb, while the Nature article is serious. The terminology used is cat state, not laser cat.
  
  --
  When all you have is a hammer, every problem starts to look like a thumb.
misuse of squarebraces by Anonymous Coward · 2019-02-02 11:14 · Score: 0

did the writer of the article summary (PolygamousRanchKid ? EditorDavid?) really need to replace the name of the subject being reported upon with some inappropriate simile? There's nothing feline or even mammal about the laser pulse, and saying "cat" repeatedly impresses an inappropriate image on the audience. If nothing else, redacting the name of the subject it makes it more difficult for us to find out more or even to talk about the subject.
I get that you want to be entertaining, but you're just handicapping your journalism.
1. Re:misuse of squarebraces by magusxxx · 2019-02-02 21:02 · Score: 1
  
  I agree. Next they'll replace 'pulse' with 'plush'. And optical fiber with 'hugging'.
  
  --
  Care killed the cat, but satisfaction brought it back.
Ripped off I tells ya!!!! by Anonymous Coward · 2019-02-02 13:21 · Score: 0

When i wear camo and shoot cats I'm hated...
But when I wear a white lab coat and shoot cats it a breakthrough!!!
Headline by Livius · 2019-02-02 13:30 · Score: 2

How can a story that starts out with an army of laser cats turn out to be so disappointing?
live for billions of years ???? by RhettLivingston · 2019-02-02 18:23 · Score: 1

An optical state can live forever. So if we had sent the pulse out into the night sky, it could live for billions of years in its [cat-like] state.
As I understand it, an optical pulse travels at the speed of light and is thus not an instant older when it is billions of light years away than it was at the moment it was produced. No optical pulse ever "lives" beyond a single quanta of time. From its point of view, it "lives" along its entire path from production to destruction in the same instant of time. Am I wrong?
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