"Quantums" here and now (part 1)
I think this topic may interest many, for recently it has become quite popular, and most importantly relevant. Well, and in order not to rant idly, I will immediately outline the direction of my stories. The main topics of my reasoning and, ideally, discussions with you, I would like to identify areas such as quantum communication and quantum computing .
But, before discussing such things, I would like to receive from you any information about what you personally would be pleased to start with. In my opinion, any conversation about quantum things of any kind should begin with an account of the basic tenets of quantum physics, but not in the form that is often presented in Russian schools and universities, but in a slightly different, more intuitive way. All that is required of you, in my opinion, is purely imagination and the presence of at least some ideas about the world around us, and it will not hurt, of course, at least some kind of built-up logic. However, I have not the slightest doubt that the readers of this portal have all this with interest. So let's get started.
But I still prefer not to start completely with this. First of all, I would like to raise the issue of relevance. Why is all this necessary? Some kind of quantum communications, quantum calculations, whether they are three times wrong, as if the classical ones are no longer suitable. What is it? Why is this? Why does modern society pay so much attention to this? The answer to madness is simple - such a hype around quantum things is caused by two main advantages: much higher performance with the highest computing power and, of course, the absolute secrecy and safety of your personal data. And, it should be noted that a significant part of the interest of the modern world community is attracted by the opportunity to leave your data unread, absolutely secret. And here the conversation is not at all about some kind of secrecy, due to the supposedly insufficient power of modern devices, but rather about the fundamental, absolute secrecy that follows from the fundamental principles of quantum mechanics. This opens up radically new opportunities for their owner, not subject to the "mere mortal."
But, it should be noted, everything is far from simple, this question is nothing more than a double-edged sword, in fact, like everything in this world. Starting from here, it is possible to trace how quantum mechanics intervenes in our reasoning. Already here we come across such a concept as superposition. In this case, it is a superposition of good and bad. Of course, this is an absolutely philosophical question, but, here I am forced to note that physics and philosophy have always been inextricably linked with each other. So let's go back to a superposition. Of course, absolute confidentiality is the dream of so many people in this world, in addition, many companies, if not all the structures and banks associated with the army, are ready to sell for the impossibility of hacking their data almost their souls. And here I propose to think about this: is absolute secrecy so good as it seems at first glance? I will leave this question solely for your consideration and I invite everyone to decide for themselves how this relates.
I want to draw attention to the fact that I personally relate to this issue exclusively from the side of a research scientist, and I would like to someday still achieve an understanding, albeit in theory, of how this should work and how to come to a replacement for the usual ones for us Now, quantum communication systems. And, consequently, in my further narration I will adhere to this point of view, perhaps I emphasize, perhaps , periodically departing in the direction of philosophical reflection, but I will try to resort to this as little as possible.
Also, do not forget about quantum computing. I would like to devote the first part of my articles to them, covering in them the basic concepts of quantum informatics mixed with the necessary mathematical knowledge. I will try to make this presentation as accessible as possible so that all information is accessible even to people without any training in the field of computer science or physics. You can ask a reasonable question - why is this necessary and what is the benefit of this? I will try to briefly answer the questions that have arisen. In the field of quantum information and quantum computing, information processing problems are being studied, which, as you can guess, can be realized and executed using quantum-mechanical schemes. Logical and simple, right? But, as it usually happens, throughout the entire history of the development of science, a rather long period of time has passed, before scientists came to this. To understand why everything was just like that, it will not be out of place to consider each of the areas that contributed to the development of this direction: computer science, quantum mechanics, information theory, linear algebra, and, of course, cryptography. It will be difficult enough to do, but I will try to present it the most interesting and exciting.
It all started with the fact that in physics at the end of the XIX century there was a significant crisis of ideas, leading to a large number of paradoxes. In view of the current situation, it was necessary to find some solution to this problem. Initially, this was an introduction to classical physics of individual special hypotheses, but, with an improved understanding of many properties of atoms and radiation, by the 20s of the XX century the necessary critical mass of knowledge had accumulated to create a new theory. She became quantum mechanics, which was successfully used to describe all kinds of objects and phenomena. So what is quantum mechanics? Quantum mechanics is nothing but a mathematical apparatus used to construct a physical theory. Roughly speaking, this is a kind of crutch necessary to build a beautiful and harmonious theory. Its principles are simple enough, but even leading experts find them contrary to ordinary human intuition. This is also evidenced by the opinions of many of the founders of this direction, who could not fully reconcile, get used to what they came up with. The sources of quantum information and quantum computing, if desired, can be seen just in the desire of physicists to better understand quantum mechanics and adapt its predictions to human intuition.
Just one of the tasks in this direction is the search for tools that would help make understanding of quantum mechanics more intuitive, and not contradicting our traditional ideas about the world. It’s much more difficult for you and me to do this, because they started laying a much more approximate and already outdated understanding of the world in us from school, and ideally, we should try to build logic differently from the very beginning, I personally see the solution in this.
For example, in the early 80s. scientists began to wonder whether it is possible to use quantum effects to transmit a signal faster than the speed of light contrary to Einstein's theory. The solution to this problem was reduced to the fact that it was necessary to understand whether it was possible to copy an unknown quantum state. If this turned out to be a completely possible thing, then it would be possible to transmit information much faster than the speed of light. It was then that the theorem on the impossibility of cloning appeared . For classical information, copying is a fairly simple and ordinary operation, while in quantum mechanics this is generally not possible.
In addition, another area of research made a significant contribution to this area, which appeared in the 70s. interest in gettingfull control over single quantum systems . Prior to this, control was usually carried out on bulk samples containing a huge number of quantum-mechanical systems, and not one was directly accessible. Here, particle accelerators came to the aid of scientists, which helped to gain limited access to this notorious control of individual systems, but it still was incomplete.
To control single quantum-mechanical systems, a large number of methods have subsequently been developed that allow one to learn many new aspects of the behavior of such systems.
So why all these delights and tricks in the direction of gaining control over such systems? If we discard various technological reasons and leave them to be exclusively scientific, the answer will be ridiculously simple - the researchers proceeded from intuitive considerations. In science, often many significant discoveries are made when a sufficient mass of results is accumulated in a new field of research. So now we are taking only the first steps in mastering this, but we have already managed to get some interesting and unexpected results. So what can we expect when we still learn to fully control individual quantum-mechanical systems and transfer these algorithms and understanding to the management of ensembles of such systems?
It is precisely the direction of quantum computing and the quantum theory of information that pushes us to search for new ways to manage these systems and to search for possibilities of applying the acquired knowledge.
And, unfortunately, despite all the efforts and popularity of this area, the results that we have today are rather poor. Modern technology is represented only by small quantum computers with a limited number of quantum bits ( qubits), as well as some optical quantum circuits. There are even implementations of quantum cryptographic systems that can make data transmission over long distances with absolute secrecy, but at the moment these are only prototypes of the necessary systems. Nevertheless, even they can now they can be quite useful in some practical specialized applications.
Let's get back to the original questions. What awaits us in the future? What is so special that quantum computing and quantum information can offer science, technology and all of humanity? What are the main problems that need to be addressed?Quantum computing and quantum information taught us to think about computing physically, so we discovered a huge number of new opportunities in the field of communication and information processing. Of course, these areas pose a lot of problems for physicists and engineers, although it is not entirely clear what this will lead to in the long run. Quantum computing and quantum information provide new opportunities to move from the simpler to the more complex. In addition, ideas from these areas allow us to form new views on physics, which is also important.
In the proposed article, some key goals and motivations that underlie the data of the areas of interest to us were rather briefly and surveyed. In addition, I tried to give a very short historical digression on the part of physics, showing part of the background that led to the advent of quantum computing and the quantum theory of information. In addition to physics, it would not hurt to consider, as I said, the history of the development of computer science, information theory and cryptography. All this I will leave for the following articles, if it causes someone interest. And today, perhaps, that's all.
Thanks for attention!
But, before discussing such things, I would like to receive from you any information about what you personally would be pleased to start with. In my opinion, any conversation about quantum things of any kind should begin with an account of the basic tenets of quantum physics, but not in the form that is often presented in Russian schools and universities, but in a slightly different, more intuitive way. All that is required of you, in my opinion, is purely imagination and the presence of at least some ideas about the world around us, and it will not hurt, of course, at least some kind of built-up logic. However, I have not the slightest doubt that the readers of this portal have all this with interest. So let's get started.
Relevance.
But I still prefer not to start completely with this. First of all, I would like to raise the issue of relevance. Why is all this necessary? Some kind of quantum communications, quantum calculations, whether they are three times wrong, as if the classical ones are no longer suitable. What is it? Why is this? Why does modern society pay so much attention to this? The answer to madness is simple - such a hype around quantum things is caused by two main advantages: much higher performance with the highest computing power and, of course, the absolute secrecy and safety of your personal data. And, it should be noted that a significant part of the interest of the modern world community is attracted by the opportunity to leave your data unread, absolutely secret. And here the conversation is not at all about some kind of secrecy, due to the supposedly insufficient power of modern devices, but rather about the fundamental, absolute secrecy that follows from the fundamental principles of quantum mechanics. This opens up radically new opportunities for their owner, not subject to the "mere mortal."
But, it should be noted, everything is far from simple, this question is nothing more than a double-edged sword, in fact, like everything in this world. Starting from here, it is possible to trace how quantum mechanics intervenes in our reasoning. Already here we come across such a concept as superposition. In this case, it is a superposition of good and bad. Of course, this is an absolutely philosophical question, but, here I am forced to note that physics and philosophy have always been inextricably linked with each other. So let's go back to a superposition. Of course, absolute confidentiality is the dream of so many people in this world, in addition, many companies, if not all the structures and banks associated with the army, are ready to sell for the impossibility of hacking their data almost their souls. And here I propose to think about this: is absolute secrecy so good as it seems at first glance? I will leave this question solely for your consideration and I invite everyone to decide for themselves how this relates.
I want to draw attention to the fact that I personally relate to this issue exclusively from the side of a research scientist, and I would like to someday still achieve an understanding, albeit in theory, of how this should work and how to come to a replacement for the usual ones for us Now, quantum communication systems. And, consequently, in my further narration I will adhere to this point of view, perhaps I emphasize, perhaps , periodically departing in the direction of philosophical reflection, but I will try to resort to this as little as possible.
Prerequisites in quantum mechanics.
Also, do not forget about quantum computing. I would like to devote the first part of my articles to them, covering in them the basic concepts of quantum informatics mixed with the necessary mathematical knowledge. I will try to make this presentation as accessible as possible so that all information is accessible even to people without any training in the field of computer science or physics. You can ask a reasonable question - why is this necessary and what is the benefit of this? I will try to briefly answer the questions that have arisen. In the field of quantum information and quantum computing, information processing problems are being studied, which, as you can guess, can be realized and executed using quantum-mechanical schemes. Logical and simple, right? But, as it usually happens, throughout the entire history of the development of science, a rather long period of time has passed, before scientists came to this. To understand why everything was just like that, it will not be out of place to consider each of the areas that contributed to the development of this direction: computer science, quantum mechanics, information theory, linear algebra, and, of course, cryptography. It will be difficult enough to do, but I will try to present it the most interesting and exciting.
It all started with the fact that in physics at the end of the XIX century there was a significant crisis of ideas, leading to a large number of paradoxes. In view of the current situation, it was necessary to find some solution to this problem. Initially, this was an introduction to classical physics of individual special hypotheses, but, with an improved understanding of many properties of atoms and radiation, by the 20s of the XX century the necessary critical mass of knowledge had accumulated to create a new theory. She became quantum mechanics, which was successfully used to describe all kinds of objects and phenomena. So what is quantum mechanics? Quantum mechanics is nothing but a mathematical apparatus used to construct a physical theory. Roughly speaking, this is a kind of crutch necessary to build a beautiful and harmonious theory. Its principles are simple enough, but even leading experts find them contrary to ordinary human intuition. This is also evidenced by the opinions of many of the founders of this direction, who could not fully reconcile, get used to what they came up with. The sources of quantum information and quantum computing, if desired, can be seen just in the desire of physicists to better understand quantum mechanics and adapt its predictions to human intuition.
Just one of the tasks in this direction is the search for tools that would help make understanding of quantum mechanics more intuitive, and not contradicting our traditional ideas about the world. It’s much more difficult for you and me to do this, because they started laying a much more approximate and already outdated understanding of the world in us from school, and ideally, we should try to build logic differently from the very beginning, I personally see the solution in this.
For example, in the early 80s. scientists began to wonder whether it is possible to use quantum effects to transmit a signal faster than the speed of light contrary to Einstein's theory. The solution to this problem was reduced to the fact that it was necessary to understand whether it was possible to copy an unknown quantum state. If this turned out to be a completely possible thing, then it would be possible to transmit information much faster than the speed of light. It was then that the theorem on the impossibility of cloning appeared . For classical information, copying is a fairly simple and ordinary operation, while in quantum mechanics this is generally not possible.
In addition, another area of research made a significant contribution to this area, which appeared in the 70s. interest in gettingfull control over single quantum systems . Prior to this, control was usually carried out on bulk samples containing a huge number of quantum-mechanical systems, and not one was directly accessible. Here, particle accelerators came to the aid of scientists, which helped to gain limited access to this notorious control of individual systems, but it still was incomplete.
To control single quantum-mechanical systems, a large number of methods have subsequently been developed that allow one to learn many new aspects of the behavior of such systems.
So why all these delights and tricks in the direction of gaining control over such systems? If we discard various technological reasons and leave them to be exclusively scientific, the answer will be ridiculously simple - the researchers proceeded from intuitive considerations. In science, often many significant discoveries are made when a sufficient mass of results is accumulated in a new field of research. So now we are taking only the first steps in mastering this, but we have already managed to get some interesting and unexpected results. So what can we expect when we still learn to fully control individual quantum-mechanical systems and transfer these algorithms and understanding to the management of ensembles of such systems?
It is precisely the direction of quantum computing and the quantum theory of information that pushes us to search for new ways to manage these systems and to search for possibilities of applying the acquired knowledge.
And, unfortunately, despite all the efforts and popularity of this area, the results that we have today are rather poor. Modern technology is represented only by small quantum computers with a limited number of quantum bits ( qubits), as well as some optical quantum circuits. There are even implementations of quantum cryptographic systems that can make data transmission over long distances with absolute secrecy, but at the moment these are only prototypes of the necessary systems. Nevertheless, even they can now they can be quite useful in some practical specialized applications.
Conclusion
Let's get back to the original questions. What awaits us in the future? What is so special that quantum computing and quantum information can offer science, technology and all of humanity? What are the main problems that need to be addressed?Quantum computing and quantum information taught us to think about computing physically, so we discovered a huge number of new opportunities in the field of communication and information processing. Of course, these areas pose a lot of problems for physicists and engineers, although it is not entirely clear what this will lead to in the long run. Quantum computing and quantum information provide new opportunities to move from the simpler to the more complex. In addition, ideas from these areas allow us to form new views on physics, which is also important.
In the proposed article, some key goals and motivations that underlie the data of the areas of interest to us were rather briefly and surveyed. In addition, I tried to give a very short historical digression on the part of physics, showing part of the background that led to the advent of quantum computing and the quantum theory of information. In addition to physics, it would not hurt to consider, as I said, the history of the development of computer science, information theory and cryptography. All this I will leave for the following articles, if it causes someone interest. And today, perhaps, that's all.
Thanks for attention!