Science-Technology
See other Science-Technology Articles
Title: Physicists manage to 'breed' Schrodinger's cat in breakthrough that could help explain the quantum world
Source:
Daily Mail Online
URL Source: http://www.dailymail.co.uk/sciencet ... -s-cat-breakthrough-study.html
Published: May 2, 2017
Author: Cheyenne MacDonald
Post Date: 2017-05-02 07:39:35 by cranky
Keywords: None
Views: 22393
Comments: 75
Scientists have developed a way to 'breed' Schrodinger's hypothetical cat in a breakthrough experiment that could bridge the gap between the quantum and the visible - or classical - worlds. The cat in the famous thought experiment can be alive and dead at the same time, in a quantum phenomenon known as superposition. But, whether this effect translates to larger objects has long remained a mystery. Physicists have now created a way to amplify pairs of classical states of light to generate 'enlarged' cats, in effort to uncover the limit (if there is one) of the quantum world. 'One of the fundamental questions of physics is the boundary between the quantum and classical worlds,' says CIFAR Quantum Information Science Fellow Alexander Lvovsky. 'Can quantum phenomena, provided ideal conditions, be observed in macroscopic objects? 'Theory gives no answer to this question – maybe there is no such boundary. 'What we need is a tool that will probe it.' In the new experiment, the researchers 'bred' the physical analogue of the Schrodinger cat. This, in this case, is the superposition of two coherent light waves, in which the fields of the electromagnetic waves point in opposite directions at once. Based on an idea first proposed over a decade ago by researchers in Australia, the team bred these states to create optical 'cats' of higher amplitudes. 'In essence, we cause interference of two 'cats' on a beam splitter,' said Anastasia Pushkina, co-author and University of Calgary graduate student. 'This leads to an entangled state in the two output channels of that beam splitter. 'In one of these channels, a special detector is placed. 'In the event this detector shows a certain result, a 'cat' is born in the second output whose energy is more than twice that of the initial one.' Doing this, the researchers converted a pair of negative squeezed 'cats' of amplitude 1.15 to a single positive 'cat' of amplitude 1.85. Doing this, the researchers converted a pair of negative squeezed 'cats' of amplitude 1.15 to a single positive 'cat' of amplitude 1.85. Entangled particles are illustrated above Over the course of the experiment, they generated several thousand of these enlarged cats. According to the researchers the experiment has implications for future work in quantum communication, teleportation, and cryptography. 'It is important that the procedure can be repeated: new 'cats' can, in turn, be overlapped on a beam splitter, producing one with even higher energy, and so on,' says lead author Demid Sychev, a graduate student from the Russian Quantum Center and the Moscow State Pedagogical University. 'Thus, it is possible to push the boundaries of the quantum world step by step, and eventually to understand whether it has a limit.' Schrödinger's cat is a thought experiment created by Austrian physicist Erwin Schrödinger in 1935. In the hypothetical experiment a cat is placed in a sealed box next to a radioactive sample, a Geiger counter, and a bottle of poison. The observer cannot know whether or not an atom of the substance has decayed, and consequently, cannot know whether the vial has been broken, releasing the poison and killing the cat, until the box is opened. This means the cat is both dead and alive inside the box, a mixture of both states, until the box is opened. 'One of the fundamental questions of physics is the boundary between the quantum and classical worlds,' says CIFAR Quantum Information Science Fellow Alexander Lvovsky. 'Can quantum phenomena, provided ideal conditions, be observed in macroscopic objects? 'Theory gives no answer to this question – maybe there is no such boundary. 'What we need is a tool that will probe it.' In the new experiment, the researchers 'bred' the physical analogue of the Schrodinger cat. This, in this case, is the superposition of two coherent light waves, in which the fields of the electromagnetic waves point in opposite directions at once. Based on an idea first proposed over a decade ago by researchers in Australia, the team bred these states to create optical 'cats' of higher amplitudes.
Post Comment Private Reply Ignore Thread
Top • Page Up • Full Thread • Page Down • Bottom/Latest
Begin Trace Mode for Comment # 36.
#1. To: cranky (#0)
No. Quantum phenomena ride on probability waves. Those waves collapse upon observation. The double-slit experiment proves this. A coin can be heads or tails -- until you look at it.
Poor cat
Maybe. Maybe not.
Maybe. Maybe not. He is in two states at the same time. I think this thread is promising. Cultural learnings of the quantum world.
No. This is a common misconception by people who don't understand the issue. The cat is only potentially in one of two states and physicists use this duality to solve certain classes of problems in physics. The cat either is or is not dead. But for the larger purposes of theory, you must treat it as though it is in an undetermined state. There is a fundamental vanity to the common misconception of Schrodinger. We presume that the state of something actually changes depending on whether a human observer is watching. But, if that is true, is Schrodinger's cat still either dead or alive depending on whether another cat sees it? How about a dog? Of course, it is nonsense. Anything that grants to mere human observation something akin to godlike powers is nothing but nonsense. And any physicist would tell you this, that you are greatly misrepresenting Schrodinger's work and that his cat is, indeed, either alive or dead at any given moment in space-time. But for theoretical constructs and calculation, we do need to assume it is both alive and dead at any given time so we can achieve higher-order theoretical constructs without having to worry about whether some guy's cat is alive or dead inside a box. Given my opinion, you can imagine how annoyed I get when people pose philosophical questions like "If a tree falls in a forest and no one is around to hear it, does it make a sound?" It's more nonsense like the common misunderstandings of non-physicists about Schrodinger. Again, the tree has fallen and it has made the same sound regardless of whether a human being heard it or not. Nevertheless, physicists do discuss this issue. I personally disbelieve this legend. Both Bohr and Einstein were too smart to take such a question seriously. Neither believed that, as a matter of physics, that human beings were the center of the universe and of reality itself. It's nothing but arrogance (and weak-minded lazy philosophy) to think otherwise.
No. This is a common misconception by people who don't understand the issue. Cats are different. How do you know, may I ask?
Because I don't fall for cheesy sophomoric pseudo-philosophy masquerading as physics. Let's return to the falling tree. Let us posit that the tree fell and that, by coincidence, someone had a sound recording device present which recorded the sound that the tree may (or may not) have made when it fell. If a human being has never heard that recording of the falling tree, did it make a sound at all? If a human being finally does hear that recording 100 years later, would we say that the tree made no sound when falling but that it finally made a sound when the recording was played 100 years later? This entire line of argument devolves into this kind of nonsense when you examine it. It is a profoundly anti-scientific view, one that denies so many other sound fundamental scientific principles. My friend, you have a vastly overinflated opinion of the importance of human beings and of observers (both human and non-human) in general. This is fundamentally an argument about the primacy of human beings to other human beings, not a serious argument about physics.
Instruments are an extension of human senses. According to one great philosopher who liked to use Occam Razor principle, the real real beings are just souls, and God would not waste his creative energies for the making material (superfluous and epistemologically inaccessible) substrate, for the perceptions and phenomena. He delivers impressions directly to the souls. And He keeps track and integrity in His mind, so recording device will get its stuff all right. What are your arguments to repudiate this?
So what? If a recording is made of the falling tree and not played until a thousand years after the tree fell, then did the sound occur a thousand years earlier (when the tree fell) or did the sound occur a thousand years after the tree fell (when a human being finally listened to that recording? Well, I would try to answer you but you seem to have confused yourself enough already. You have to be joking. This is ignorance on steroids. If you (and all other living persons) have never heard a live performance by the opera singer Enrico Caruso from a century ago, would you then say that Caruso never sang at all despite the many written accounts of his performances? If you do listen to that recording by Caruso, then can Caruso finally be considered to have sung Ave Maria only now, a century later? Or can you rely on rumors and opinions held by others that Caruso did indeed sing Ave Maria? Or did Caruso finally exist for you when you finally heard him sing that song (because God kept all His electrons in line)? Good thing that God is keeping all these pesky details straight for you because you seem far too confused to sort any of it out. OTOH, my practical opinions have no such problems and do not require massive intervention from God to create grammophones, and recording devices and conversions to digital formats and the creation of the internet, all so that I can hear Caruso (or that Caruso can finally be considered by me to have sung Ave Maria). My framework requires only classical physics and an ordinary human agency. Any time you conceive the universe as some great Clockwork that only God can keep wound up and running so it won't collapse upon itself, you have not found a special wisdom or insight. A true god does not have to wind His clock(s) because He does not subject Himself to the mere physical constraints of His own creation or the grossly inadequate understandings of his own (allegedly) intelligent creations.
Isn't this like it's not news unless CNN and Hufpo report it?
Only to people who think Newton and Einstein were ignorant. : ) Who knew you could get this many replies on a physics thread at LF? LOL
There are no replies to Comment # 36. End Trace Mode for Comment # 36.
Top • Page Up • Full Thread • Page Down • Bottom/Latest"Can quantum phenomena, provided ideal conditions, be observed in macroscopic objects?"
#2. To: misterwhite (#1)
#3. To: A Pole (#2)
Poor cat
#5. To: misterwhite, Deckard, Vicomte13, ConservingFreedom, Willie Green, hondo68, calcon, TooConservative (#3)
Poor cat
#6. To: A Pole (#5)
He is in two states at the same time.
Albert Einstein is reported to have asked his fellow physicist and friend Niels Bohr, one of the founding fathers of quantum mechanics, whether he realistically believed that 'the moon does not exist if nobody is looking at it.' To this Bohr replied that however hard he (Einstein) may try, he would not be able to prove that it does, thus giving the entire riddle the status of a kind of an infallible conjecture—one that cannot be either proved or disproved.
#7. To: Tooconservative (#6)
He is in two states at the same time.
Again, the tree has fallen and it has made the same sound regardless of whether a human being heard it or not.
#8. To: A Pole (#7)
How do you know, may I ask?
#9. To: Tooconservative (#8)
Let us posit that the tree fell and that, by coincidence, someone had a sound recording device present which recorded the sound that the tree may (or may not) have made when it fell. If a human being has never heard that recording of the falling tree, did it make a sound at all?
#11. To: A Pole, redleghunter, Vicomte13 (#9)
Instruments are an extension of human senses.
According to one great philosopher who liked to use Occam Razor principle, the real real beings are just souls, and God would not waste his creative energies for the making material (superfluous and epistemologically inaccessible) substrate, for the perceptions and phenomena. He delivers impressions directly to the souls.
And He keeps track and integrity in His mind, so recording device will get its stuff all right.
Ave Maria
#35. To: Tooconservative (#11)
If you do listen to that recording by Caruso, then can Caruso finally be considered to have sung Ave Maria only now, a century later? Or can you rely on rumors and opinions held by others that Caruso did indeed sing Ave Maria? Or did Caruso finally exist for you when you finally heard him sing that song (because God kept all His electrons in line)?
#36. To: redleghunter (#35)
(Edited)
Isn't this like it's not news unless CNN and Hufpo report it?
Replies to Comment # 36.
[Home] [Headlines] [Latest Articles] [Latest Comments] [Post] [Mail] [Sign-in] [Setup] [Help] [Register]