The development is another important step on the long road to developing a quantum computer
The basic unit of modern electronic computers, the transistor, can be in one of two possible states (eg, zero or one). Therefore, the testing of the solutions using it is done serially. In contrast, a quantum transistor may exist in several states at the same time. This feature is at the core of the effort to build quantum computers, which, it is hoped, will be able to test a huge number of solutions in parallel, and thus be infinitely more efficient and faster than today's computers.
The parallel operation capability of a quantum transistor stems from a basic feature of quantum theory, according to which the given particles in a closed system can be simultaneously in several states. This phenomenon, called superposition, exists only if no one observes or measures the particles. That is, when a quantum system is observed or measured, its parallel existence collapses into one of the possibilities of "only" existence. Therefore, in order to maintain the parallel operation capability of a transistor, it is forbidden to "peek" into the system. From a practical point of view, this means that the system must be well isolated, to prevent any leakage of information from the system to the outside, and that any interaction between the system components and themselves, and between them and the external environment, must be prevented.
In fact, complete preservation of the superposition is currently possible only in very simple systems, consisting, for example, of individual atoms, which communicate with each other through individual photons (particles of light). Photons are particularly good candidates to serve as the basis of communication within such quantum systems, because by their nature they do not interact easily.
Now they did Dr. Barak Dayan and the members of his group - Itai Shomaroni, Serge Rosenblum, Yulia Lovsky, Oral Bechler and Gabriel Gendelman - from the Department of Chemical Physics in the Faculty of Chemistry at the Weizmann Institute of Science, a significant step in this direction. They succeeded, for the first time in the world, in building a photonic transistor - a quantum device based on a single atom that performs a switching operation for individual photons (similar to an electronic transistor that switches electric currents).
At the heart of the system developed by the scientists is an atom that can be in one of two states, and accordingly transfers photons to the right or left - according to the instruction it received from the previous photon: in one state, photons coming from the right are transmitted by it to the left. The arrival of a photon from the left causes it to be returned in the same direction, reversing the state of the atom. In the opposite state, photons arriving from left to right are transmitted, and a photon arriving from the right is returned, reversing the state of the atom. In this way, an alternating circuit breaker is created, which is activated exclusively by means of single photons - without the need to activate other external fields on the system. Thanks to this, it is possible in principle to attach the basic units to each other in a complex system. The units will pass the photon stream between them, and each of them will activate the next one in line and determine its directionality.
This achievement,Published this week in the scientific journal Science, was made possible thanks to the combination of two innovative technologies. One technology makes it possible to trap and fix atoms inside an empty cell using laser beams and magnetic fields for a long enough period of time to have an encounter with the photon stream. Another technology is responsible for bringing the photons to the meeting. Their capture is carried out in tiny resonators (resonators) on a chip, in which the photons circulate for an extended period of time. Resonators of this type, produced by photolithographic methods similar to the technology used to manufacture chips, are considered the best resonators in the world today, and enable the well-controlled interaction between the photons and the atom. Dr. Dayan was a partner in the effort to combine these two technologies several years ago, during his post-doctoral research at the California Institute of Technology, and today his laboratory at the Weizmann Institute of Science is one of a handful of laboratories around the world that implements them.
Dr. Dayan: "The road to building a quantum computer is still long; But the system we created demonstrates basic principles that may be applicable in future architectures of such a computer. The principles we demonstrated in this device, in which a single atom functions as a transistor - or toggle switch - for photons, can form the basis for building future quantum networks where there will be many passive devices that communicate with each other only through photons, including networks that will be based on base components that are not necessarily atoms. In the following studies we hope to demonstrate more such devices, which will be operated exclusively by photons, such as a quantum memory or a logic gate".
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"Originally" because there are additional dimensions here and also the influence of things from the future, I am honored that in this post I have not yet been smeared in a "serious" way. Thank you blowing water
Honorable Mr. Shmulik, it is difficult to eliminate probabilities completely because there will always be missing knowledge that we can do statistics on, however the multiplicity of worlds eliminates the need to say that the randomness that statistics are applied to is a fundamental property of nature in the original
Nissim and elbentzo Thank you very much for the answers.
Miracles, the article is fascinating. I didn't really understand what it means to "remove randomness from quantum mechanics". The two-slot experiment would still show entanglement and besides, doesn't Everett's multiplicity of worlds inherently eliminate probabilities?
thank you for the answer.
There is an interpretation by three Italian scientists, if I remember correctly, who talk about a very rare spontaneous collapse at the level of the individual particle. According to them, once there are many particles together, it is likely that at least one will collapse and drag the entire measuring system and the measured particle after it, if I understood correctly.
I'm not a physicist, so it's possible that I'm talking nonsense, but maybe it can be said that there is a very rare particle in nature that simply doesn't enter a state of superposition (perhaps it doesn't have particle-wave duality) and in a measuring device that contains masses of particles, it's likely that it will too and will drag the whole system after it? Or to say that there is a rare combination of particles that causes the wave function to collapse and in a measuring device it is likely that this combination will be found?
Just an idea…
Hello Elijah,
My point is that physicists who are not involved in the field can afford to choose the interpretation that suits them only based on what is most intuitive to them. Among the people who deal with interpretations (by the way, this field is between physics and philosophy and many of the physicists who study it publish articles in philosophy magazines) have other considerations, so I do not pretend to speak for them. Since I don't work with these people either, my experience doesn't teach me about their opinions.
My personal opinion, as I wrote, is that as long as we do not have an experiment (or a thought experiment) that indicates differences between the interpretations, each physicist is allowed to choose the interpretation that is most intuitive to him. I find an interpretation of the collapse of the superposition as a result of a forced transition from the quantum to the classical world much more intuitive than a splitting into different worlds. But as usual, I will emphasize that I do not pretend to claim that the interpretation that is convenient for me is correct or that the others are wrong.
elbentzo
You say that "among physicists who do not deal with the basics of quantum mechanics (that is, whose research does not concern questions like "What is the correct interpretation?"), the most popular interpretation in my experience is Copenhagen." Does this mean that for those who do deal with the subject, the accepted interpretation is *not* Copenhagen?
By the way, what is your personal opinion on the matter?
And one more thing, I used to think that whoever would explain or sell the knowledge of how to turn back time would earn a lot of money. I made billions from returns, but again, but - transparent
Something about superposition in the classical world, superposition in the classical world is possible after time reversals even if its size and complexity is greater than a particle. For example - you will sit on an armchair after repeating the time, you will put the name of a chair, if you treat both in a similar way in your behavior, you will feel them in a super position and although intelligence is also involved in the example, you will be able, for example, in the armchair to feel the virtual and partial folding of the legs resulting from the transparent chair. Respectfully blowing water
Hello Shmulik,
I will start by emphasizing that this is currently a popularity test, since we do not (yet) have an experiment that differentiates between the different interpretations. I wouldn't want you to think I'm saying that the multiple worlds interpretation is wrong.
So yes, among the physicists who do not deal with the basics of quantum mechanics (that is, whose research does not concern questions like "What is the correct interpretation?"), the most popular interpretation in my experience is Copenhagen. Contrary to Carroll's words, her mechanism is not so far-fetched, although it is not explicitly found in the Schrödinger equation (and in this sense, the mathematical structure of the multiple worlds is more compact).
Carroll presents things the way he thinks is right, and although you can't complain about that (each of us presents things as he sees and understands them), he doesn't give the reader enough room to understand why people reject the interpretation. As he himself wrote, he doesn't really say anything in favor of it but mainly shows that it is not ridiculous and that it brings the same results we know (through the decoherence mechanism). The criticisms about her that he rejects are a bit stupid and therefore there is a kind of straw man here - to show that a stupid criticism is stupid does not mean that the claim criticized is true.
At the end of the day, I can't point out his mistake to you, and that's because these are interpretations - and not (as far as we know) distinct physical theories. He addresses this in one line, but this is an important detail - if the whole issue is indeed indistinguishable from an experimental point of view and it is only about bookkeeping means, then it is natural to choose an approach that provides us with a better intuition. There is no doubt that the Copenhagen approach is much more intuitive, so it is natural that many physicists will use it to interpret quantum mechanics.
The strongest demagogic element in the blog (demagoguery is a strong word that suggests malicious intent. I use it in the sense of "rhetoric that sounds logical but is actually misleading" and not claiming that Carroll is lying or deliberately misleading) is in his analysis of system development with a measuring device. He "shows" that by the simple requirement that the measuring device can also be in superposition, it is guaranteed that several parallel wave functions exist and decoherence causes them to not interact - that is, multiple worlds. But in fact there is an implicit assumption here of how the measurement works. In the same way, we could take an approach that says that the measuring device (which is necessarily classical) cannot be found in superposition (just as no classical system can be found in superposition), and the interaction between the device and the quantum system is expressed in a unitary operator that imposes the state on one of the eigenstates that make it up. Sorry for the somewhat technical language, if it's not clear it's not the end of the world. The bottom line is that we could have done a different treatment of the problem that would not have allowed multiple worlds and would have resulted in the same result. Therefore, the argument in favor of the multiple worlds put forward by Carroll contains an implicit assumption that the correct treatment of the problem is the one that is consistent with multiple worlds.
And again to finish, I'm not trying to say that the interpretation is wrong. I don't deal in this field and I don't understand a lot about it. But it is important to understand that multiple worlds, at least as of today, is one approach among many that leads to exactly the same result and that it is less intuitive than the alternatives.
Shmulik
Here's an interesting article on:
http://www.wired.com/2014/08/multiverse
Miracles,
Say, you don't recognize a ghost when you smell a troll like that? 🙂
elbentzo
What is the popular interpretation of quantum mechanics today? Copenhagen yet?
How about Shane Carroll's column? He often tells thanks to Everett's multiple worlds:
http://www.preposterousuniverse.com/blog/2014/06/30/why-the-many-worlds-formulation-of-quantum-mechanics-is-probably-correct/
Ainsh,
The uproar I started was over the form of expression of your response (something I did not find in your response to me), it was very violent and out of place.
Because Albenzo, who wanted to help, first of all wrote 'Shema Shetel said'... then he added more information. What's wrong with adding more information? It helps people like me who find it very difficult to understand quantum physics to understand it little by little...
If you didn't want them to get confused, you should have written something along the lines of: "Don't get confused, superposition does not directly answer Yona and Yossi's questions."
See the difference?
As something tries to help, don't attack it, it doesn't help anyone. Even if I think I'm right, I don't yell (unless I'm yelled at).
I'm not a so-so gentle person, in my previous response I tried to understand why you used such a firm tone? Now I see you want to help too, just not in the right way.
Allow me to help you in the future (I hope this doesn't come across as condescending, that's not the intention):
Don't attack people personally, don't use expressions like "confuse the mind", say the content you want to say without offending the other.
It's simple, it's much nicer and most importantly it will make people take you seriously and not as a troll.
I hope I also helped in some way.
Best regards,
winter
X
The things I said do not appear in the article. In the second paragraph, the principle of superposition is explained without mentioning the fact of measuring it in the laboratory or describing a simple experiment that does this, and later the transistor is described that is built on the principle's existence, but again - it is not explained to the lay reader how to see that this principle does exist in nature.
I did not address the original question because Tal gave an explanation that, in relation to its essence, is completely clear and reasonable, and therefore (contrary to your claims) I chose not to "confuse the minds" of the other commenters by corrupting empty words.
I advise you to stop and disappear. You entered the pit, you can't get out. You tried to come off as smart, to get an ego boost, but you just sink into your comments which are not only quite nasty but also full of stupidity:
1. You accused me of not understanding the question when I clearly wrote that I was not answering the question but adding an interesting piece of information.
2. You claimed that I explained what superposition is, when I did not give any explanation for it, but only described an experiment that shows how it is measured in the laboratory.
3. You wrote that the interpretation of the multiple worlds is popular among the world of physics...
4. You wrote that if Hawking believes in something, then we should all worship him because he is smarter than us (the most anti-scientific attitude I have come across). By the way, when you said Hawking put me in the small pocket, then based on which of my publications did you say that? I mean, which works of mine did you read, understand and based on which you determined that there is no place to hear my opinion? I'd love to talk to you about the work I'm posting, I'm sure you could enlighten my eyes and teach me a thing or two about physics.
5. You claimed that an explanation for the existence of superposition as a measurable physical phenomenon and a description of an experiment that measures it appears in the article, when it does not.
You don't get smarter and smarter with each comment. So like I said, either you derive satisfaction from the very antagonism you create here (=troll), or you don't understand what a joke you are making of yourself. Anyway, good luck.
Einstein
Is your name a first or second derivative of the name Einstein? Why are you a scientist? I deal with quantum processes of non-linear photons in parallel universe number 4.
bootleg
It might be necessary - so I won't risk it and - in advance I apologize for what I will write, because you are probably a very gentle person.
I draw your attention to two questions that were asked here at the beginning of the discussion. Yossi and Yona's reactions.
The story went like this:
Yossi asks:
"Why does the system crash when you watch? How does viewing affect at all? Is there something physical that goes through the viewing? please the smart one"
Please note: commenter Yossi uses the word "watching" 3 times.
He uses the word "watching" in every one of his sentences.
(He also asked us to wise him up... or wise him up or something like that - and you are not ashamed!)
The second event was when the commenter Yona asked: "Why does watching a phenomenon change it?? What passes from the observer to the observed???"
Note 2: Commentator Yona used the word "viewing" 3 times.
He used the word "watching" in every one of his sentences.
(He even used the word "viewing" twice in one sentence! Interesting right?)
Now notice how many times they used the word "view".
Hmmm.. I wouldn't have guessed the correct lottery numbers if their emphasis was on the word "watching".
Like a good scientist, I suspect (for now only suspicions) that they (Yossi and Yona) wanted to know (as I wrote in my first response): why observing a photon causes a wave function to collapse (when the emphasis is on the word "observation").
And to this I tried to draw the wandering attention of Albenzo. that's it. I don't understand what the commotion and all the traram you created is about. My reaction was completely legitimate. All the best.
Albanzo
You say you didn't write what superposition is. But, you actually contributed to the discussion when you added information about the principle of superposition... hmm..
In fact, the article itself already had this information. I mean, not only did you not answer a question asked here. In general, you gave a different answer to a question that was not asked. (On the science website this phenomenon is called "miracles" syndrome)
What you added..already existed. There was no need for you to add what you added. This essentially makes the value of your donation zero.
So your last comment was unnecessary. It would be better if you answered the question instead of confusing the readers who do not know physics at the level of Stephen Hawking (or…… as in your level/Einstein/Podolsky), even more.
Do you want me to remind you of the question they asked?
There is no point in referring. Either it's a troll, or just an idiot. Anyway, have fun.
And for the benefit of the other readers - I'll just clarify (although I'm pretty sure it's clear from the original response) that contrary to what was said here, I did not explain what superposition is, but contributed to the discussion the fact that the collapse of the Hegel wave is not just a mathematical structure but a physical effect measured in a laboratory.
Einstein
Einstein would throw up if he read your ugly comment.
Einsteinzo, why violently though?
"Instead of confusing the brain", "Put you in the little pocket"
Your formulations are irrelevant, everyone here is trying to help. Instead of creating a discussion you create a battle.
Correction: affects the photon in this way.
Albanzo
You have a reading comprehension error.
Ask: Why does the cause of the collapse of a photon's wave function affect the collapse in this way.
And no: what is superposition.
You, as someone who claims to be a scientist, should know that there is no answer to this yet, and from that your answer should have been: I don't know. (instead of confusing the minds of the readers).
My second point: the interpretation of the multiple worlds is actually the most popular among the interpretations and one of its supporters is Stephen Hawking.
You will probably agree with me that Hawking has you in the small pocket when it comes to physics.
So why should we listen to you and not someone who understands many times more than you on the subject?
Tuthomas
to dirt You can laugh a little, you can't curse.
Honorable Mr. Thutomas, it's good to have this
Water blowing
The stupidity blows out of your throat and pollutes the environment. Please fold up, enter one of your worlds and stay there, lest you contaminate the remaining worlds with your failures.
Dear Mr. Skeptic, because I write a bit like Beda Zeh Vu, and remember a little the spirit of future responses, and their spirit, I sometimes skip the next answer and write before it in order to change a little bit and maybe delete in the future, a response that I am not satisfied with, I do not object with all my might, but if They laugh and write in my name and nickname, be respectful
to blowing water,
to each one of them.
Assuming that there are parallel worlds and in each parallel world there is another surfer named "Blowing Water" - is it possible that all the aforementioned surfers are able to meet each other and argue with each other in the forum?
Isn't it appropriate for each such surfer to use a nickname with a specific marking for the parallel world to which he belongs? After all, without marking, we will part with great confusion.
Sincerely.
Honorable Mr. Albanzo, after I got to rub it in a bit, also on the practical side, it was easier for me to talk about it. With respect also according to the interpretation of the parallel worlds
It is important to note that the multiple worlds interpretation mentioned here is only one of several interpretations of quantum mechanics, and not even the most popular of them. I would not use it to explain quantum mechanics because, contrary to what Tal and I have written, it is not in the scientific consensus and has no proof or evidence to its credit that has been tested in the laboratory. It is an idea that may or may not be true, but without a doubt quantum mechanics lives and breathes even without it.
As usual, they started laughing and writing in my name, a short continuation, and regarding what goes on if you watch, it's a bit like every action has a reaction, only that the reaction is in parallel worlds and therefore statistical. Shia also with respect
From many transitions between parallel worlds I lost direction. Are any of the readers willing to reset me? please i come
And continue to the honorable Mr. Yossi, when you stand on the parallel world of the particle or in other words its superposition, there is a standing on your world through the connection between the parallel worlds and as we know it returns in time through its connection and "collapses" in time. Again with respect to blowing water
Honorable Mr. Yona, when you observe a particle and it is in superposition, or in similar words and somewhat at an angle, it is in parallel worlds, you stand on its world, and if it has a broad statistical expression, it is reduced to your world. Respectfully blowing water
In my previous response there are many typographical errors due to the fact that I wrote it on the phone. Hope it's clear though.
The things that Tal wrote are completely correct, but I would like to add one important point to them: the collapse of the superposition can be verified and measured in the laboratory.
The privatization experiment can be described as follows: a particle is introduced into the system, a kind of maze that has one entrance and several exits. We don't look at all what happens inside the maze, that is, we have no idea which of the different tracks the particle is already on. Years detectors at the different exits from the maze and check from which exit the particle came out. We repeat the experiment many times until we have the probability distribution that the pieces came out of each exit. This distribution is mathematically consistent with the description of a particle going through all trajectories simultaneously! On the other hand, if we put detectors inside the maze to see what's going on inside, suddenly the experiment has completely different results that fit the classical description of a particle that goes through only one of the randomly chosen paths.
That is, when we did not measure the position of the particle while inside the maze, it could be in a superposition of states (go through several paths at the same time), but the interaction with the measuring device in the second version of the experiment caused the "collapse" of the wave function and forced the particle to move in one path only.
Yossi Viona: In order to "observe" a quantum system, or measure certain values from it, some kind of interaction with it is necessary. In order for us to receive meaningful information (a number displayed on a screen for example), the interaction must be with a "classical" system, i.e. ordinary objects from our world (for example an ordinary electronic chip), of classical physics. A "classical" system has one definite permanent state (if we don't enter into different interpretations and theories), which we perceive with our normal senses. The interaction between the quantum and classical world "causes" the collapse of the quantum system (again, without different interpretations such as multiple worlds, etc.).
To read more about the "measurement problem" on Wikipedia:
http://he.wikipedia.org/wiki/%D7%91%D7%A2%D7%99%D7%99%D7%AA_%D7%94%D7%9E%D7%93%D7%99%D7%93%D7%94
Why does viewing a phenomenon change it?? What goes from the viewer to the thing being watched???
Why does the system crash when watching? How does viewing affect at all? Is there something physical that goes through the viewing? Please be smart