That's a hard question. Except for ... that it is entirely possible that I am one. And thus I might well be qualified to say something about it.
If that is indeed so, the first thing to say about it is that it feels neither as quantum nor as computational. You know, quantum in the sense of very small pieces, the smallest possible units. It doesn't feel like little bits. It feels like one coherent, continuous something. Analog, not digital.
And does it compute? Is it calculations? Doesn't feel like it. Computation is what you need to do to construct something out of pieces that aren't exactly ri
That's a hard question. Except for ... that it is entirely possible that I am one. And thus I might well be qualified to say something about it.
If that is indeed so, the first thing to say about it is that it feels neither as quantum nor as computational. You know, quantum in the sense of very small pieces, the smallest possible units. It doesn't feel like little bits. It feels like one coherent, continuous something. Analog, not digital.
And does it compute? Is it calculations? Doesn't feel like it. Computation is what you need to do to construct something out of pieces that aren't exactly right for it. Simulation. Making one thing appear to be another. But what about the most basic thing? Doesn't feel like computation is needed there. It is maybe the only thing that isn't computed.
The way we talk about it and think about it is probably far removed from what it really is, and those words are a sign of that. Basically, there's a scarcity of dimension in our ability to understand it. The basic stuff of existence has many dimensions. 11 dimensions if string theory is right. Something that is unified, unbroken and unbounded in a space with many dimensions might well appear to consist of scattered little pieces when seen through a lower number of dimensions. It might take complicated calculations to predict or describe the movement of those pieces in that lower dimensions, whereas in the higher dimension it takes none. And, most likely, a lot of it will appear incomprehensible and entirely random when seen with too few dimensions.
Of course it is meaningful to talk about "what it is like" to be that which everything is made of, that which everything is, that which an infinity of other things can come from. It is wildly pretentious of us humans to even consider the idea that we little temporary 3 dimensional creatures would be the only ones in existence to have a conscious experience, or that it somehow would be a superior experience to all others, and we're the only ones who can figure things out. And what a depressing thought too.
It appears to me that the unified universal process is perfectly well sentient and self-aware. I mean, if 11 dimensions and unbroken unity between all actual and possible events, past, present, or future, in any number of parallel universes - if that wouldn't be enough to be spectacularly conscious, then I don't know what would be. And I'm really understating the whole thing by many orders of magnitude.
What's it like? We can apparently only guess about what it's like to be the whole thing. But at the same time, if our own consciousness is of the same nature, it tells us everything we need to know. You can see the universe in any pebble on the beach. Awareness itself might be basic stuff. It feels like being aware.
It feels like pure awareness. This state is not self-aware or aware in any complex way, it is pure and simple awareness. It is a basic primal apprehension that is the simple reception of and response to information.
Seen from the outside the process seems like a coherent flow and transformation of information (computation), whilst seen from the inside it seems like the coherent apprehension / experience of information (awareness).
First some clarifying remarks before addressing the question in more detail...
Re: 'computation'
To many people the term 'computation' is associated with "something th
It feels like pure awareness. This state is not self-aware or aware in any complex way, it is pure and simple awareness. It is a basic primal apprehension that is the simple reception of and response to information.
Seen from the outside the process seems like a coherent flow and transformation of information (computation), whilst seen from the inside it seems like the coherent apprehension / experience of information (awareness).
First some clarifying remarks before addressing the question in more detail...
Re: 'computation'
To many people the term 'computation' is associated with "something that electronic computers do", which often extends to "calculations that mathematicians do". BTW the term 'computer' was initially the title for a mathematician's assistant who performed routine calculations.
I agree with most of what Flemming says, however I agree with his comments about 'computation' only within the context of this meaning of computation:
And does it compute? Is it calculations? Doesn't feel like it. Computation is what you need to do to construct something out of pieces that aren't exactly right for it. Simulation. Making one thing appear to be another. But what about the most basic thing? Doesn't feel like computation is needed there. It is maybe the only thing that isn't computed.
I agree with this because the state of pure awareness does not involve anything remotely like "performing mental arithmetic", in fact pure awareness is the complete absence of any complex states of being. Hence pure awareness is non-computational given this meaning of the term 'computation'. Lets refer to this meaning as computation(1).
However there is a deeper meaning to 'computation'. In a very general context computation is the coherent flow and transformation of information. In this general sense, some examples of phenomena that exhibit computation are electronic computers, RNA/DNA/protein cycles, perception and interpretation by the mind, evolution of quantum wavefunctions, particle interactions, etc. In fact, every system exhibits this form of computation. Lets call this meaning computation(0).
To understand how the two interpretations of 'computation' relate, consider an analogy of a virtual universe that contains myriad complex dynamical systems, some of which are sentient beings, mathematicians or electronic computers. From the perspective of the sentient beings computation(1) is what mathematicians and electronic computers do. Whilst computation(0) is that which animates the virtual universe and underlies every phenomenon and event within the virtual universe.
Hence electronic computers are an example of a device that can harness computation(0) and convert it into computation(1). This is analogous to how a dynamo converts energy that is inherent in the universe into a usable form that we call electricity. The dynamo doesn't create energy and computers don't create computation(0).
What is it like to be a quantum computation(0)al process?
Computation(0) is not self-aware or aware in any complex way, it is pure and simple awareness. It is a basic primal apprehension that is the simple reception of and response to information. It is this that animates the systemic dynamics within which we are emergent complex systems.
Without its stream awareness a system could not apprehend or interact with other systems. All complex interactions are composed of simpler interactions between sub-systems. Similarly all complex states of consciousness are composed of simpler states of consciousness.
It is only through complex feedback loops and self-organising cognitive structures such as memory, personality, world-view, life-story, etc that awareness becomes aware of awareness and grows towards sentience. Hence that which we experience as awareness, consciousness, mind, sentience etc are all high level complex forms of pure awareness or computation(0).
This is a form of pan-psychism, in particular pan-proto-experientialism, Russellian monism, Type F monism or Neutral monism (google them http://bit.ly/c947lG). These are the view that consciousness is constituted by the intrinsic properties of reality. “On this view, phenomenal or proto-phenomenal properties are located at the fundamental level of physical reality, and in a certain sense, underlie physical reality itself.” (Blackwell Guide to Philosophy of Mind http://bit.ly/apaaPe).
Very simple cases such as the quantum computational process underlying a particle would have a very basic stream of awareness, whilst very complex cases such as that underlying a human being have rather high degrees of sentient consciousness.
There is a discussion of these general issues in the ebook System Science of Virtual Reality http://bit.ly/9XhElB . It takes a very mathematical, systematic approach. Of particular relevance to here, it derives the Schrödinger equation (core dynamical equation of quantum mechanics) within the conceptual framework of simulated systemic virtual reality. Which indicates that quantum processes are isomorphic to the computations of a general system simulator and that classical systems are isomorphic to virtual systems. The computational processes animate the experiential processes within the virtual systems and are thus isomorphic to what we call awareness, consciousness, etc.
For more see:
- Hard Problem of Consciousness
- Consciousness: What is consciousness?
- What is sentience?
- Is the Universe a Simulation?
- Is it possible to create a general system simulator, if so how?
- In simple terms, what does the Stern-Gerlach experiment imply about the nature of quantum systems and observable phenomena?
- What do the results of the PEAR GCP ICRL experiments say about consciousness and how can we scientifically explain them?
The question is ill specified. You guys are just using fancy words in place of having a true understanding. Can any of you please explain what quantum computational processes have to do with consciousness? What would make you even infer such a theory? Quantum computation hasn't even been observed. Even if it had been observed you are discussing the implementation of a computation (consciousness) rather than the computation itself. I believe that consciousness has nothing to do with the hardware that is computing it. I understand that people want to understand how our brain computes consciousne
The question is ill specified. You guys are just using fancy words in place of having a true understanding. Can any of you please explain what quantum computational processes have to do with consciousness? What would make you even infer such a theory? Quantum computation hasn't even been observed. Even if it had been observed you are discussing the implementation of a computation (consciousness) rather than the computation itself. I believe that consciousness has nothing to do with the hardware that is computing it. I understand that people want to understand how our brain computes consciousness, as I myself am one of these people. What I do not understand is trying to answer questions like this by making arbitrary theories that have no basis whatsoever in observed phenomena. I would compare this to trying to sort a list of integers by randomly permuting it until it is finally sorted.
I do believe that consciousness will someday be explained; furthermore I believe that it will someday be programmed. I do not believe the explanations for it will be nearly as contrived this page suggests.
Before this field can move in a positive direction we need to define what it means for something to be conscious. If we cannot do this then there is no way to test whether or not something is conscious; thus any discussion of the matter is moot.
Below is an accurate complete description of quantum computing. We will explain the quantum computer as a shell game without using physics or math. Inside each shell (qubit) there is either a pea or a cashew. We start with a 1,000 qubits like Dwave (see Google and NASA develop the quantum processor 'D-Wave 2X system').
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Game Setup
The game begins with the game setup. Let's take the case where we begin with 360 qubits, which we treat as (walnut) shells. A magician then waves a wand and each shell is 50% likely to have a pea
Below is an accurate complete description of quantum computing. We will explain the quantum computer as a shell game without using physics or math. Inside each shell (qubit) there is either a pea or a cashew. We start with a 1,000 qubits like Dwave (see Google and NASA develop the quantum processor 'D-Wave 2X system').
-----------------------------------------------------------------------
Game Setup
The game begins with the game setup. Let's take the case where we begin with 360 qubits, which we treat as (walnut) shells. A magician then waves a wand and each shell is 50% likely to have a pea inside, and 50% likely to have a cashew inside. The magician again waves his wand and each of the 360 shells has four numbers written inside it, one red one green one black one white, all equal to 1/2. We denote the colored numbers as {R,G,B,W}. The remaining 640 shells are occupied by cashews, and inside is written in color {R,G,B,W}={0,0,1,0}. As the game progresses we get to swap peas and cashews and mess around with the colored numbers. But we never get to look inside until game over. By the way the colored numbers give the probabilities, probability of (pea)=the sum of the squares of R and G, likewise probability of (cashew) is the sum of squares of B and W.
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Game Rules
Now the game starts. At each stage in the game You, the quantum programmer, are allowed to do only three things, without ever being allowed to look into any shell. The game is over whenever you choose to open up all the shells. Programming a quantum computer is all about choosing which moves to make in what order so when you open up the shells you find the list of ones [peas] and zeros [cashews] equal the "exact" answer you seek.
Wait what? This is not at all how we program digital computers!
If you open the shells and don't get the correct answer after a few preassigned number of tries the house (quantum) wins. If you get the answer you seek within the allotted tries you win. We have proofs that we can indeed solve certain important math problems, assuring the house loses with very very high probability. This is the only game where you are (nearly) guaranteed to beat the house instead of vice versa!
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The Three Permissible moves at each play
1) Double tap move: To begin we need to introduce the concept of a flip. In a flip move the pea becomes a cashew if we started with a pea or the cashew becomes a pea if we started with a cashew. You tap any one of the 1,000 shells with your left hand and tap another shell with your right hand. The magician assures that right hand shell is flipped if there is a pea in the left hand shell, and the right hand shell is left the way it started if the left hand shell is a cashew. Again you are not allowed to look into any shell before during or after this or any other move.
2) Color number swap: You pick any shell, and you pick either the pair of numbers {R,G} or {B,W}. Call the choice {a,b}.
Replace {a,b} by {[math]\frac{a+b}{\sqrt{2}},\frac{a-b}{\sqrt{2}}[/math]}. No further operation is required since probabilities are unaffected.
3) Probability fiddle: You again can point to any one shell. Then the magician waves his wand and the new colored numbers are
{[math]\frac{R+B}{\sqrt{2}},\frac{G+W}{\sqrt{2}},\frac{R-B}{\sqrt{2}},\frac{G-W}{\sqrt{2}}[/math]}. The magician waves his wand again and replaces the pea or cashew with the ensuing probability. [This move and only this move requires quantum systems to execute.]
That's all there is to it! The above rules are simple and complete. Yet, you should convince yourself that under the shell a lot of stuff is happening. For example if we execute move 3 a sum total of 1,000 times we have generated up to [math]~10^{300}[/math] different outcome lists. This is a lot! Even for 360 moves to just list, let alone optimize over, all the possible combinations of peas, and cashews, classically [i.e. using Newton's laws which digital computers do] would require every atom in the universe starting from the beginning of time, printing out one 360 bit combination one billion times a second. Thus, Quantum computers can optimize over lists that cannot even be described "Newtonially" by all the universe's atoms, printing lists at a 1GHz rate, using all the time since time began. This is causing some philosophers fits! I just think it is really really exciting! [The challenge is that the programming shell game is very hard as the odd rules below evince. Another challenge: We must assume there is a way to quickly check if your answer is correct or else everything falls apart.]
For you quantum experts out there you may recognize that I have described the universal Quantum gate set [math]R(\pi/4) [/math], controlled-not, and Hadamard, and that colored markings are the real and imaginary entries of the unitary qubit operator. I obviously used an arbitrary initial state, and don't discuss post measurement iteration such as needed in Shor's algorithm, nor do I discuss convergence rate, I don't "warn people" that the Dwave is only adiabatic not general, I leave out almost surely asymptotic, reversibility, yadda yadda. These are true but irrelevant facts you don’t need to know them to play the described quantum shell game. I claim the game itself adequately describes exactly what quantum computing is.
It is like being a theorist, a coder and an experimenter all at once. And it is a lot of fun!
The first step in doing computational physics is the theory. You pick the kind of model you want to employ to the study the class of systems you are interested in. Of course, there are going to be various approximations involved. You have to find the right balance between finding a model that is good enough to study the system but at the same time tractable through theory and computation. Then you do the actual math. In the case of electromagnetism, this would involve a lot of vector calculus. There is
It is like being a theorist, a coder and an experimenter all at once. And it is a lot of fun!
The first step in doing computational physics is the theory. You pick the kind of model you want to employ to the study the class of systems you are interested in. Of course, there are going to be various approximations involved. You have to find the right balance between finding a model that is good enough to study the system but at the same time tractable through theory and computation. Then you do the actual math. In the case of electromagnetism, this would involve a lot of vector calculus. There is a lot of scribbling in notebooks and on whiteboards, and a lot of Mathematica.
Typical whiteboard in the office. Ignore the creepy German guy on the right.
Once the math is done comes the part where you translate all that into code. This involves coding a lot and swearing a lot at compiler errors and obscure library dependencies. Of course it never works correctly the first time. Or the hundredth time, for that matter. So you stare at plots till you can figure out where the errors come from, and at numbers till you find the source. And you debug and debug and debug…
Ninja amoeba, the fierce guardian of numerically inaccurate magnetic fields. Don't remember how many debugging cycles it took to fix this guy.
Hmm, the error has to be here somewhere…
Once it is all fixed (or so you think), comes the most fun part - numerical experimentation. Find interesting systems and study interesting physical phenomena. Think wild, and experiment. You are not constrained by the experimenter's nightmares. You can simulate hollow nanoparticles sitting in vacuum, and why not?
Life cycle of a simulation : Simulate, post-process, plot and discard…
How many cores and how much RAM did you say your comp has?
And while studying some systems, you have that Eureka moment when you find something totally unexpected. After the initial excitement has subsided, you go and check to make sure that it is not a numerical error. If not, yaaaaaay.
In the end, you get some nice-looking figures. This one from Internal optical forces in plasmonic nanostructures, © 2015 Optical Society of America.
Of course, things are not so linear as presented here. Many a time, you have to go back and improve the math or the code when you find that the method is not so accurate as you wished. There is also quite a bit of code modification later to improve the speed of the program when the whole lab starts using it to do hundreds of simulations. There is also the "bargaining" discussion with real experimenters, which goes roughly like this:
I want to fabricate this system and study this effect. Can you simulate it?
No, I can't. Because this, this and that.
But I want to simulate it. It will be really interesting.
Hmm, well, I can approximate the system with this. This thing will change, but the feature you are looking for should still arise at roughly the same wavelength.
But the system has this.
Dude, this is all the program can do. Everything will have to be completely rewritten to incorporate this thing that you want. And even if I do, we don't have the computational power for that. Have you seen how your fabricated structures look? Trust me, the fabrication defects will affect the result way more than this simplification.
Okay…
C'est la vie.
PS: I defended my PhD thesis titled "Modelling of plasmonic systems: Advanced numerical methods and applications" recently. My thesis involved developing computational tools based on a numerical method called surface integral equation to study the response of metallic nanostructures to light. I was interested in various effects like scattering, optical forces and rotation, surface charges and Raman scattering.
Thanks for the A2A.
Well, you tell me. We are all in the ‘quantum’ realm. The universe is largely quantum mechanical. The laws of quantum physics account for most of the phenomena that we observe in the universe. It is the single most successful theory in physics ever discovered.
On the other hand, several notions about quantum physics that Ant Man discusses aren’t true. For instance, its not true that time and space lose all meaning in the quantum realm. In fact, time and space both occupy a very special place in quantum physics. Quantum physics can also be constructed to be compatible with rel
Thanks for the A2A.
Well, you tell me. We are all in the ‘quantum’ realm. The universe is largely quantum mechanical. The laws of quantum physics account for most of the phenomena that we observe in the universe. It is the single most successful theory in physics ever discovered.
On the other hand, several notions about quantum physics that Ant Man discusses aren’t true. For instance, its not true that time and space lose all meaning in the quantum realm. In fact, time and space both occupy a very special place in quantum physics. Quantum physics can also be constructed to be compatible with relativity.
Lots of questions.
Look, you are right to be suspicious of hype. I wish more people were. I wish the guys who cooked up the term “quantum teleportation” would be made to suffer for it! But quantum information processing (QUIP) is real enough, and the people who work in the field inventing ingenious algorithms to do calculations by manipulating entangled qubits are doing serious work that will probably have real applications in the coming decade. The guys at D-wave (some of whom started out in our CIfAR group at UBC) have sold several expensive “quantum computers” already; I put the term in quot
Lots of questions.
Look, you are right to be suspicious of hype. I wish more people were. I wish the guys who cooked up the term “quantum teleportation” would be made to suffer for it! But quantum information processing (QUIP) is real enough, and the people who work in the field inventing ingenious algorithms to do calculations by manipulating entangled qubits are doing serious work that will probably have real applications in the coming decade. The guys at D-wave (some of whom started out in our CIfAR group at UBC) have sold several expensive “quantum computers” already; I put the term in quotation marks because they admit that theirs are not “full-blown” QUIP machines — but they do do some things really fast, I hear.
Beyond the confusion produced by unbridled hype, there are a couple of problems with QUIP:
- Difficulty: I mean difficult to understand. I went to a few lectures by Bill Unruh when he was trying to bring us (his colleagues) up to speed on QUIP, and while I was excited and enthusiastic for the first 2 or 3 hours, after that it all went over my head. It became obvious that I was not going to be able to understand the autocorrection algorithm without a great deal of real work, I decided to be satisfied with an “informed layman’s” understanding. Shame on me! So you should beware of taking my opinions too seriously. However, I suspect I am not alone in this. Beware of QUIP pontifications generally!
- Decoherence: in order to do QUIP with entangled qubits (whatever kind you prefer — D-wave uses superconducting qubits made from d-wave cuprates, hence the name) you have to keep them coherent and entangled long enough to finish the manipulation. This turns out to be difficult, for a variety of reasons. They are, after all, quantum states of very small and delicate things. The “decoherence time” is a popular figure of merit — the longer the better.
- Utility: contrary to popular misconceptions, QUIP is not going to make your smartphone apps or your web browser or your email run faster; “classical” computers (the kind we have now) do that just as well as QUIP, probably better! And speculations about QUIP facilitating virtual consciousness are almost certainly just more examples of unbridled hype. What QUIP is really good for is
- Busting encryption. If your public/private keys involve the product of two huge prime numbers, the NSA dream-QUIP would be able to report what those factors were in one swift operation. Goodbye privacy! Hence the megabucks being poured into such research by spy agencies.
- Modeling quantum systems. If you are trying to predict the behavior of a large number of quantum mechanical entities strongly coupled together (like in magnetism, superconductivity or protein folding), what better way to simulate same than coupling together a large number of entangled qubits in an analogous scheme? This does mean that any high-end desktop gaming computer in 2030 will feel totally left out without a QUIP peripheral processor. And probably the VR you upload your consciousness into in 2050 will have a whole stack of them! ;-)
- Identifying a good problem to solve is as important as actually solving it
(not unique to the field, but particularly pertinent) - Making sure you have the technical background for a given problem is even more important - you may need anything from combinatorics and number theory to numerical analysis and Lie groups, matrix decompositions and various algorithms, of course quantum theory, and of course digital logic.
- It is really easy to overlook something fundamental or some research done on the same problem, but worded very differently.
- Once you solve an interesting problem, it's not entirely cle
- Identifying a good problem to solve is as important as actually solving it
(not unique to the field, but particularly pertinent) - Making sure you have the technical background for a given problem is even more important - you may need anything from combinatorics and number theory to numerical analysis and Lie groups, matrix decompositions and various algorithms, of course quantum theory, and of course digital logic.
- It is really easy to overlook something fundamental or some research done on the same problem, but worded very differently.
- Once you solve an interesting problem, it's not entirely clear where to publish the results and what presentation style to use for the paper - is your work Math, Computer Science, Engineering or Physics? Even once you decide where to publish, it's not entirely clear how to motivate the work.
- People not working on quantum information processing can have very different attitudes to the field, ranging from "oh, cool" to "that's just bad science, man".
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Where do I start?
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Here is a list of the top savings accounts available today. Deposit $5 before moving on because this is one of the biggest mistakes and easiest ones to fix.
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The quantum realm in physics is the scale where quantum mechanical effects become important when studied as an isolated system. Typically, this means distances of 100 nanometers or less or at very low temperature. More precisely, it is where the action or angular momentum is quantized.
I majored in quantum physics and minored in philosophy. Or rather, I did what I think is the equivalent to that in a Danish university (half year of philosophy studies, two and a half years of physics, and a thesis on quantum information theory).
It’s awesome. Quantum mechanics and especially quantum information science are probably the most mindblowing subjects I’ve encountered. I view it as a huge privilege to have had the ability to spend the time and get the guidance to get a grasp of it.
There are side effects I hadn’t considered before I chose my specialization. For some reason, many peopl
I majored in quantum physics and minored in philosophy. Or rather, I did what I think is the equivalent to that in a Danish university (half year of philosophy studies, two and a half years of physics, and a thesis on quantum information theory).
It’s awesome. Quantum mechanics and especially quantum information science are probably the most mindblowing subjects I’ve encountered. I view it as a huge privilege to have had the ability to spend the time and get the guidance to get a grasp of it.
There are side effects I hadn’t considered before I chose my specialization. For some reason, many people are convinced that the prefix ‘quantum’ automatically makes any given subject ten times more difficult, so for instance, if you tell people you study physics, many will have a ‘meh’ reaction, whereas if you say you study ‘quantum’ physics, (some) people will be blown away by how intelligent they think you are, even though in truth, no subfield is inherently more difficult than another.
It also means that you’ll catch yourself giggling nine out of ten times you hear someone starting a sentence with ‘well, according to quantum mechanics’.
Thanks for the A2A! To any answer that says completely that they know what Quantum Physics entail, they’re completely wrong. We have no idea what Quantum Physics really means, so I’m going to go with what we have so far. Quantum physics is what is extremely small, so small that it’s smaller than the nuclei of atoms, and the electrons in an atom. But the Quantum Particles are extremely fast. As an example, let’s say that there is a girl named Eva, and her quantum twin, Ave. If Ave was on one side of the universe, and Eva was on the other, they would do the exact same thing. This is extremely im
Thanks for the A2A! To any answer that says completely that they know what Quantum Physics entail, they’re completely wrong. We have no idea what Quantum Physics really means, so I’m going to go with what we have so far. Quantum physics is what is extremely small, so small that it’s smaller than the nuclei of atoms, and the electrons in an atom. But the Quantum Particles are extremely fast. As an example, let’s say that there is a girl named Eva, and her quantum twin, Ave. If Ave was on one side of the universe, and Eva was on the other, they would do the exact same thing. This is extremely important in Quantum Computing, as this makes it so that they can communicate at speeds faster than light, without killing anyone. They Quantum particles also have a superposition, making it so that if the Quantum particle was a nickel, it would be on it’s side, rather than being on A or B, which is how normal computers work. They are either on A or B, so because of this, the Quantum Particle as a processor would be extremely fast. Why don’t we do this already then, you may ask? The reason is because the superposition only works at temperatures of (or very close to) absolute zero. However, Quantum computing, if harnessed, would be as comparable to normal computers as a cell phone is to an abacus.
The obvious answer would be: it entails almost everything we know about Nature! (with the notable exception of General Relativity) However I will assume that the question was more specific and philosophical : what is the single most important implication of quantum mechanics for the way we see Nature? In that case my answer would be the following: the impossibility to observe Nature without affecting it irreversibly. Before QM the accepted vision of science was quite deterministic: the real world follows some laws, humans can discover these laws and therefore predict the future behaviour of an
The obvious answer would be: it entails almost everything we know about Nature! (with the notable exception of General Relativity) However I will assume that the question was more specific and philosophical : what is the single most important implication of quantum mechanics for the way we see Nature? In that case my answer would be the following: the impossibility to observe Nature without affecting it irreversibly. Before QM the accepted vision of science was quite deterministic: the real world follows some laws, humans can discover these laws and therefore predict the future behaviour of any system. In practise this could be extremely difficult or require huge computational power, but in principle it should be possible. In short we believed in deterministic laws. QM changed that vision completely as it turned out that every measurement affects a quantum system in unpredictable ways. For instance if I was to see an electron I have to shine a photon on it, but the energy of the photon will completely change the state of the electron! Obviously if I shine a bit of light to take a photo of a tennis ball I will not affect it in any observable way, as the energy of light in this case is so much smaller than the energy of the ball. However for quantum objects this to true. This is a pure experimental fact of QM and it cannot be deduced by any logical deduction. Indeed I would consider it the main axiom of QM. There has been very recently considerable effort in theoretical research to reformulate the foundations of QM in order to reflect this principle.
If you are starting to fantasize about the mind changing the physical world, multiple versions of yourselves and other more or less misguided interpretations of the consequences of this principle, I need to disappoint you. Such misguided visions are mostly popularised by people who never studied QM. Even physicists applying every day the formalism of QM struggle with its comprehension, as a physicist I certainly do. I believe the misinterpretation comes from implying the presence of human beings in the measurement process. After all a single atom cannot ‘measure’ another atom, or can it? Indeed it turns out that it can!
The correct formulation of the principle stated before should indeed be in informational terms. A system A cannot acquire information about a system B without disturbing it irreversibly. Information is a physical quantity, at par with energy, as it is well understood in thermodynamics. I believe this single fact of Nature has dramatic consequences for our vision of the world. Determinism collapses. The quantum world is continuously in the process of being made, mostly in unpredictable ways. The whole universe is not a gigantic mechanic clock like we thought 100 years ago. It is more like a living being, evolving, complex, with a ‘life of its own’.
What I said is not the only discovery of QM. For instance QM also says that there is a minimum amount of information that 2 systems can exchange (a quantum precisely, corresponding to Plank constant). Entanglement, non locality and other weirdnesses entails from these 2 basic principles put together. However I personally feel that the axiom of information=disturbance has the most important consequences for the way we see the world and human knowledge.
Q:What would gaming be like using quantum computers?
You would win all your games and lose all your game in parallel at exactly the same time.
First of all, this is all hypothetical and my point of view.
Let's start playing quantum ping-pong.
The Quantum realm starts from nearly 100 nanometers or less. So to play quantum ping-pong we need to get that small in scale and dimension. Also, it needs a low temperature. Now our size is comparable to a few atoms.
The net is made up of a 2d infinite potential barrier. A single electron is used as the ball.
Let's see how it will be different from the normal table tennis we play in the macroscopic world.
- By using an infinite potential barrier, there is quite a large probability that even if you hit
First of all, this is all hypothetical and my point of view.
Let's start playing quantum ping-pong.
The Quantum realm starts from nearly 100 nanometers or less. So to play quantum ping-pong we need to get that small in scale and dimension. Also, it needs a low temperature. Now our size is comparable to a few atoms.
The net is made up of a 2d infinite potential barrier. A single electron is used as the ball.
Let's see how it will be different from the normal table tennis we play in the macroscopic world.
- By using an infinite potential barrier, there is quite a large probability that even if you hit the ball in the net, it will act as a wave and lose some of its energy but will pass through the barrier. So better be active while playing. It is unpredictable.
- The first point was still a bit easy. But now, in the quantum realm, the electrons behave weirdly. The electron can be at multiple places at one instance. But there's a catch! Your size is too comparable to an electron and so you can also be at multiple places. So it is hard to imagine that there will be multiple balls on the table and you will be playing all the balls at once.
- Now comes the spooky effect. If there is another electron entangled with your ball then there will be another table where the ball will exactly behave the same. And its action will be highly predictable.
If you want to see how it goes then you should probably experiment it on a quantum computer and see the results.
It would look something like this:
Enjoy imaging how it feels playing quantum ping pong....
Quantum Computing is a relatively new branch of computing developed through Quantum Mechanics.
In classical computers,
The smallest pieces of information are on something called “Bits”.
Each bit can have a value of either 1 or 0.
With 1 bit, there can be 2 values possible.
With 2 bits, 4 values
With 3, 6 values and so on.
The quantum computing uses the principle of Quantum entanglement and Quantum Superposition.
In Quantum Superposition, a subatomic particle is said to be in all possible states at the same time. Only when it is observed does it assign itself a particular value.
In Quantum entanglement,
Quantum Computing is a relatively new branch of computing developed through Quantum Mechanics.
In classical computers,
The smallest pieces of information are on something called “Bits”.
Each bit can have a value of either 1 or 0.
With 1 bit, there can be 2 values possible.
With 2 bits, 4 values
With 3, 6 values and so on.
The quantum computing uses the principle of Quantum entanglement and Quantum Superposition.
In Quantum Superposition, a subatomic particle is said to be in all possible states at the same time. Only when it is observed does it assign itself a particular value.
In Quantum entanglement, the particles are entangled i.e when 1 particle is observed, it takes a specific value and its entangled pair takes the opposite value at the same instant, irrespective of how far they are !
So in Quantum computing, instead of bits they use qubits i.e Quantum bits.
While bits take either 1 or 0 as its value,
Qubits take both 1 and 0 as its value.
With 1 qubit, 2 values
With 2, 4 values
With 3, 8 values
With 4, 16 values and so on.
In short,
while bits take values which are multiples of 2
Qubits take values which are POWERS OF 2.
THIS MAKES THE CALCULATION PROCESS insanely fast.
To break into a 64 bit encryption will take a classical computer decades,
A Quantum computer will do the job in minutes.
That is how insanely powerful Quantum Computers are.
On the scale of worst to best-
Classical conputers< Super Computers < Quantum Computers.
The future is Quantum Computing and with it Artificial Intelligence is just a few minutes ago. Quantum Computers are the key to the evolution of the Human Race and the its becoming an Inter- Galactic Civilization!!!!!!!!!!
Let me compare this to working hard to build a beautiful, ornate subway station, hoping that the trains will come and have somewhere else to go. Every hour, someone new walks in and says "I think I hear a train coming,... oh never mind". Don't get frustrated because it wasn't even clear you could build what you have built --- keep up the great work! Then it turns out that there is a whole bunch of people building subway stations (of different designs) in many places, some people are digging tunnels, and there are even new tracks in several places. But the trains haven't showed up yet. Should b
Let me compare this to working hard to build a beautiful, ornate subway station, hoping that the trains will come and have somewhere else to go. Every hour, someone new walks in and says "I think I hear a train coming,... oh never mind". Don't get frustrated because it wasn't even clear you could build what you have built --- keep up the great work! Then it turns out that there is a whole bunch of people building subway stations (of different designs) in many places, some people are digging tunnels, and there are even new tracks in several places. But the trains haven't showed up yet. Should be here any minute now!
For those saying quantum computers wouldn't be useful, this is highly likely incorrect.
We don't know the full space of quantum algorithms yet but we do know that it's good at quantum/physical calculations (ie, materials modeling, quantum phenomena modeling).
This in addition to the fact that we'll be pushing most aspects of gaming onto the cloud means that we'll likely be using hybrid classical quantum simulations for games. With quantum likely giving massive gains in rendering/materials, physics simulation, and AI.
It is unlikely to be used for the basic logic of a game though. Although if ever
For those saying quantum computers wouldn't be useful, this is highly likely incorrect.
We don't know the full space of quantum algorithms yet but we do know that it's good at quantum/physical calculations (ie, materials modeling, quantum phenomena modeling).
This in addition to the fact that we'll be pushing most aspects of gaming onto the cloud means that we'll likely be using hybrid classical quantum simulations for games. With quantum likely giving massive gains in rendering/materials, physics simulation, and AI.
It is unlikely to be used for the basic logic of a game though. Although if everything moves over to a purely systems approach and there is no set logic, just basic physical rules. It could all be quantum yeah.
How did you come to imagine there is such a thing as a ‘quantum realm’? All the word ‘quantum’ means is a minimum quantity of a form of energy, like a quark, or photon, or electron, etc. These quantum entities are called in QFT (quantum field theory) ‘excitations of the field’. A field is a physical expression of opposing forces in dynamic equilibrium; the dynamism of that energetic transaction results in the field oscillating and the quantum excitations are the peaks of those oscillations. Not a realm, just a condition of nature.
The answer that follows is somewhat vague, but should give a general idea. It is difficult to be precise without delving too deeply into the quantum mechanics.
A conventional computer works by performing operations on bits that can be in two states: zero or one. A computer with N bits can then be in 2^N possible states. According to quantum mechanics, however, an object can exist in more than one state simultaneously - we say that such an object is in a superposition of states. In principle, any object can be in a superposition of states, but controlling and observing this phenomenon can be
The answer that follows is somewhat vague, but should give a general idea. It is difficult to be precise without delving too deeply into the quantum mechanics.
A conventional computer works by performing operations on bits that can be in two states: zero or one. A computer with N bits can then be in 2^N possible states. According to quantum mechanics, however, an object can exist in more than one state simultaneously - we say that such an object is in a superposition of states. In principle, any object can be in a superposition of states, but controlling and observing this phenomenon can be quite tricky. If you can make a system of bits that exist for a long enough time in a superposition of their possible states, you can sort of perform many computations simultaneously.
For example, consider an operation that takes two bits as an input, and gives two bits as an output. There are four input and output states, which we can write as |01>, |10>, |00>, and |11>. In a classical computer, you can choose one of them as your input and see what the output is. In a quantum computer, you can input all four states at once, in a superposition, |01>+|10>+|00>+|11>. (In general, you can input all 2^N states at once, with N quantum bits.) Unfortunately, then your output may also come out as a superposition, and measuring and interpreting this state is quite tricky. This is why designing algorithms for quantum computers is very difficult, and only a handful have been developed. But for the algorithms that do exist (one notable one being for factoring large numbers), the speedup is supposed to be exponential, roughly corresponding to trying one input at a time in the classical case vs. all 2^N inputs at the same time in the quantum case.
Moore's law is always on your side so your laptop is a supercomputer that your predecessors from the 90's would have dreamed to work on. Software and coding is now awesome to where you don't have to always work out the nitty-gritty of difficult algorithms. Physics prefers simpler problems so you don't spend as much time studying complex technicalities as you would CS or engineering. Still you get to make a career out of trying to make computers your bitch. Overall it's great.
Let us understand how a quantum computer works, by using the Deutsch–Jozsa algorithm.
A classical computer scenario:
- Suppose there are eight persons in a theater where you are a gatekeeper. To find out whether more people are males or females, you will need to observe at least first five persons while they are exiting.
- [math]2^{n-1} + 1[/math] observations are needed for deciding the polarity of [math]2^{n}[/math] (classical-type) objects, which are not in quantum entanglement.
A quantum computer scenario:
- Suppose there are eight bidirectional fans in a theater where you are a gatekeeper. To find out whether more fans are f
Let us understand how a quantum computer works, by using the Deutsch–Jozsa algorithm.
A classical computer scenario:
- Suppose there are eight persons in a theater where you are a gatekeeper. To find out whether more people are males or females, you will need to observe at least first five persons while they are exiting.
- [math]2^{n-1} + 1[/math] observations are needed for deciding the polarity of [math]2^{n}[/math] (classical-type) objects, which are not in quantum entanglement.
A quantum computer scenario:
- Suppose there are eight bidirectional fans in a theater where you are a gatekeeper. To find out whether more fans are facing the gate or facing the stage, you will need to observe only once whether the air is blown towards the gate.
- [math]1[/math] observation is sufficient for deciding the polarity of [math]2^{n}[/math] (quantum-type) objects, which are not in quantum entanglement.
Specific problems depend on the choice of information carriers, such as photons, nuclear spins, trapped ions, superconducting currents, etc. However, the general problem is the fragility of quantum states - they tend to decay and must be isolated as much as possible from everything else, which complicated operations on quantum states.
Photons have zero rest mass, so it's difficult to "store" them. Superconductors require very small temperatures. Nuclear spins are difficult to address individually if you are maintaining many of them. Trapped ions are typically arranged on a line, and only neares
Specific problems depend on the choice of information carriers, such as photons, nuclear spins, trapped ions, superconducting currents, etc. However, the general problem is the fragility of quantum states - they tend to decay and must be isolated as much as possible from everything else, which complicated operations on quantum states.
Photons have zero rest mass, so it's difficult to "store" them. Superconductors require very small temperatures. Nuclear spins are difficult to address individually if you are maintaining many of them. Trapped ions are typically arranged on a line, and only nearest neighbors can interact (it's a bit more complicated, but you get the idea).
Maintaining a large number of controllable and addressable particles is difficult - experimentalists have not figure out how this can be done. Also, the frequent errors require large amounts of error-correction, which requires more particles.
Ah, I see the question has changed between the A2A that arrived in my mailbox, and its current manifestation. The one I was responding to was, “How would quantum computing work?” I will leave my reply for the moment, but will remove it once there are some answers to your revised version of the question.
The best analogy (well, really more a back-of-the-envelope model) that I have seen is for finding solutions to the traveling salesman problem.
Imagine taking a map of the country in question, and sticking pins in the cities that the salesman has to visit, and then stretching an elastic band so th
Ah, I see the question has changed between the A2A that arrived in my mailbox, and its current manifestation. The one I was responding to was, “How would quantum computing work?” I will leave my reply for the moment, but will remove it once there are some answers to your revised version of the question.
The best analogy (well, really more a back-of-the-envelope model) that I have seen is for finding solutions to the traveling salesman problem.
Imagine taking a map of the country in question, and sticking pins in the cities that the salesman has to visit, and then stretching an elastic band so that it visits each and every pin. Then, you press some sort of “run” button, and the elastic band shortens itself down (so that it is less stretched) by sorting out a bit order of visiting each of the pins.
The challenges therefore can be seen to lie in how we represent the map to the quantum computer, how we represent the need to remain in contact with each and every pin, and how to read out the final configuration of the elastic band. The pressing of the “run” button is surprisingly the least of the problems, since it is only an instruction to tell the machine to find its least energy position, which is what it was wanting to do anyway.
Yes - but you shouldn’t do it for the money.
Assuming you do love quantum computing though, here is some extra motivation for you:
There is a lot of money (24,000,000,000 US dollars) being pumped into this industry and it is only going to grow.
Yes - but you shouldn’t do it for the money.
Assuming you do love quantum computing though, here is some extra motivation for you:
There is a lot of money (24,000,000,000 US dollars) being pumped into this industry and it is only going to grow.
Quantum computer is an application of quantum mechanics which is called quantum computing, so to understand what quantum computer do for us you need to understand quantum mechanics.
The computers we have been using since early 19th, the are application of Electromagnetism a field of physics which gave us transistors, once we had transistors we made those computer which we modified their speed and size through time, the speed of those computers are enough for personal usage even today, even to carry out some ordinary stuffs, the transistors based computers are binary meaning they only spin on an
Quantum computer is an application of quantum mechanics which is called quantum computing, so to understand what quantum computer do for us you need to understand quantum mechanics.
The computers we have been using since early 19th, the are application of Electromagnetism a field of physics which gave us transistors, once we had transistors we made those computer which we modified their speed and size through time, the speed of those computers are enough for personal usage even today, even to carry out some ordinary stuffs, the transistors based computers are binary meaning they only spin on and off possiblity, when it comes to quantum it's is called qubit meaning it can spin infinite possible ways, but we need quantum computs to modify Health sector ( quantum computer will help us find new complex medicines) it will help us in industrial production by making a copy of chamicals which are limited in nature, so that our agricultural sector will rise again, it will improve every sector, because it deals with high energy and it consider every possible way to solve a problem…
Quantum computers perform calculations based on the probability of an object's state before it is measured - instead of just 1s or 0s - which means they have the potential to process exponentially more data compared to classical computers.
Classical computers carry out logical operations using the definite position of a physical state. These are usually binary, meaning its operations are based on one of two positions. A single state - such as on or off, up or down, 1 or 0 - is called a bit.
In quantum computing, operations instead use the quantum state of an object to produce what's known as qub
Quantum computers perform calculations based on the probability of an object's state before it is measured - instead of just 1s or 0s - which means they have the potential to process exponentially more data compared to classical computers.
Classical computers carry out logical operations using the definite position of a physical state. These are usually binary, meaning its operations are based on one of two positions. A single state - such as on or off, up or down, 1 or 0 - is called a bit.
In quantum computing, operations instead use the quantum state of an object to produce what's known as qubit. These states are the undefined properties of an object before they've been detected, such as the spin of an electron or the polarization of a photon.
Rather than having a clear position, unmeasured quantum states occur in a mixed 'superposition', not unlike a coin spinning through the air before it lands in your hand.
These superposition can be entangled with those of other objects, meaning their final outcomes will be mathematically related even if we don't know yet what they are.
The complex mathematics behind these unsettled states of entangled 'spinning coins' can be plugged into special algorithms to make short work of problems that would take a classical computer a long time to work out... if they could ever calculate them at all.
Such algorithms would be useful in solving complex mathematical problems, producing hard-to-break security codes, or predicting multiple particle interactions in chemical reactions.
Quantum computing supremacy
For the time being, classical technology can manage any task thrown at a quantum computer. Quantum supremacy describes the ability of a quantum computer to outperform their classical counterparts.
Some companies, such as IBM and Google,claim we might be close, as they continue to cram more qubits together and build more accurate devices.
Not everybody is convinced that quantum computers are worth the effort. Some mathematicians believe there are obstacles that are practically impossible to overcome, putting quantum computing forever out of reach.
Time will tell who is right.
Yes. A lot of graph theory stuff lately, and some predictive models. Here's a talk my research partner and I gave at PyData Miami 2019 (Xanadu's qumodes simulator to mimic their hardware in Python): https://www.slideshare.net/ColleenFarrelly/pydata-miami-2019-quantum-generalized-linear-models
Many quantum hardware companies provide Python packages that simulated their machines. Researchers and some small start-ups have access to the actual device and can use it for benchmarking new algorithms against classical solutions.
For background, I worked in quantum computing for a couple of years at IBM Research. I wouldn’t say that I “went into the field of quantum computing” because there are very few actual jobs outside academia in quantum computing. This is because there aren’t actually any commercially useful quantum computers in existence and pretty much all of the jobs are in research.
( And yes, there is DWave, which has a quantum annealer which is commercially available, but it is not considered a general purpose quantum computer and I don’t know that many jobs exist using, maintaining or programming them. )
Absolutely! They are just very difficult to keep in the proper state. Usually they are thick, protecting walls in freezing chambers and liquid nitrogen, perhaps, and definitely magnetic confinement. Particles from the world, the “outside” world, can mess up the order that is needed to compute anything, or particles from space (cosmic rays) do the same. It is hard to shield the atoms we use to compute properly, hence arrayed correctly, in their magnetic bottles of confinement. So we have a hard time quantum computing because the quantum particles which are what gives the quantum computer its po
Absolutely! They are just very difficult to keep in the proper state. Usually they are thick, protecting walls in freezing chambers and liquid nitrogen, perhaps, and definitely magnetic confinement. Particles from the world, the “outside” world, can mess up the order that is needed to compute anything, or particles from space (cosmic rays) do the same. It is hard to shield the atoms we use to compute properly, hence arrayed correctly, in their magnetic bottles of confinement. So we have a hard time quantum computing because the quantum particles which are what gives the quantum computer its power in the first place, are so darn delicate. But we do have them. The Chinese, to our American dismay, have already used quantum entanglement (one important aspect of QC) between one of their orbiting satellites containing entangled particles, and with the entangled entangled particles, in a lab here on the ground, to “send a message” of a sort (quantum entanglement is complicated, but basically — if you mess with one entangled particle its partner in entanglement automatically — instantly, faster than light, no matter how far away or where it is located — truly instantly reacts, FTL communication, but we really cannot use it. The problem is that any information sent either way, if you will, still has to travel at best at the speed of light. So Einstein’s speed limit still applies. We can’t send any information FTL. So how can we use this property of quantum particles ? Figure it out and you will win a Nobel Prize for sure).
Also, QC use “QUBITS” as their “unit,” similar to how we use BITS. QC make use of quantum mechanical properties in their QUBITS that allow the simultaneous computation of trillions of different possible problem solutions, and can crack any code we can devise. So the current 1024-bit (or whatever number of bits it is up to) and RSA code system will be useless. But think of the math problems we can solve! Think of the AI we can create! There you go. Soon, I’m sure we are 30 years farther along over at DARPA (google this acronym), than the public knows.
So think of a way to use quantum entanglement’s FTL communication to send meaningful information FTL! Win that Nobel!
Yes, this subject is complicated as heck.
“why do conscious observers like us perceive the particular Hilbert space factorization corresponding to classical space (rather than Fourier space, say), and more generally, why do we perceive the world around us as a dynamic hierarchy of objects that are strongly integrated and relatively independent? This fundamental problem has received almost no attention in the literature” Max Tegmark, MIT Physicist: http://arxiv.org/pdf/1401.1219v3.
While the obvious answer is that the quantum world is exactly what it looks like today, to you; it is interesting to speculate as to how an alternative “Hilb
“why do conscious observers like us perceive the particular Hilbert space factorization corresponding to classical space (rather than Fourier space, say), and more generally, why do we perceive the world around us as a dynamic hierarchy of objects that are strongly integrated and relatively independent? This fundamental problem has received almost no attention in the literature” Max Tegmark, MIT Physicist: http://arxiv.org/pdf/1401.1219v3.
While the obvious answer is that the quantum world is exactly what it looks like today, to you; it is interesting to speculate as to how an alternative “Hilbert space factorization” might look.
My answer to the Quora Question: What are quantum effects in simpler terms? explains six effects:
1. Interference
2. superposition
3. probabilistic outcomes
4. entanglement
5. Action at a distance
6. The uncertainty principle
None of these effects show themselves at human everyday scales. Instead, we experience the averaged result of these effects operating on billions of particles at scales smaller than the nano.
Qubits are the core of a quantum computer, and they use the weirdness of atomic physics to do things that seem literally impossible.
A qubit doesn't have "true" and "false" but rather "any mixture of true and false" - some state a(true)+b(false) such that a+b =1.
Alone, that would be relatively less useful, except for the curious property of entanglement:
two qubits aren't individually mixtures of true and false once entangled. Instead, they're a combined mixture of TT, TF, FT, and FF (with 4 coefficients adding up to 1).
The basic idea in quantum computing is that you can run algorithms that ta
Qubits are the core of a quantum computer, and they use the weirdness of atomic physics to do things that seem literally impossible.
A qubit doesn't have "true" and "false" but rather "any mixture of true and false" - some state a(true)+b(false) such that a+b =1.
Alone, that would be relatively less useful, except for the curious property of entanglement:
two qubits aren't individually mixtures of true and false once entangled. Instead, they're a combined mixture of TT, TF, FT, and FF (with 4 coefficients adding up to 1).
The basic idea in quantum computing is that you can run algorithms that take in those entanglements of lots of combinations of true and false, and the algorithm, in a (very real) sense, runs on each of the individual combinations of T and F.
For example, an algorithm that maps the second bit to true would turn the above from aTT+bTF+cFT+dFF into (a+b)TT+(c+d)FT.
[disclaimer: it wouldn't actually. this is a huge simplification of the math involved]
I'm being extremely imprecise here, but: if you can imagine making a huge set of entangled states represent "every possible answer" to something at the same time, and then applying algorithms that collapse all of those states into only the correct answer, you can see how a quantum computer can do so much more than a classical one. By collapsing a huge entangled state into a small one, we can (sorta) crunch an algorithm on an exponential number of inputs ( 2^ the number of entangled qubits) simultaneously.
This means previously unrealistic problems that took exponentially long for large inputs become somewhat more tractable.
Among other things, the ability to factor prime numbers quicker than we currently can would mean that all modern cryptography would be useless and you could (in theory) break into banks and intercept messages and really do whatever you wanted. Fortunately quantum computers should also allow for more safe communication to counteract that.
Of course, quantum computing is still in its infancy, and it's considerably more complicated than classical computers were to develop. Someday in the future, though, we all might have quantum modules in our laptops that do all our cryptography/prime factoring, and maybe many years after that we'll do everything on quantum circuitry.
IBM scientists have built a quantum processor that users can access through a first-of-a-kind quantum computing platform delivered via the IBM Cloud onto any desktop or mobile device. IBM believes quantum computing is the future of computing and has the potential to solve certain problems that are impossible to solve on today's supercomputers.
The cloud-enabled quantum computing platform, called IBM Quantum Experience, will allow users to run algorithms and experiments on IBM's quantum processor, work with the individual quantum bits (qubits), and explore tutorials and simulations of what might
IBM scientists have built a quantum processor that users can access through a first-of-a-kind quantum computing platform delivered via the IBM Cloud onto any desktop or mobile device. IBM believes quantum computing is the future of computing and has the potential to solve certain problems that are impossible to solve on today's supercomputers.
The cloud-enabled quantum computing platform, called IBM Quantum Experience, will allow users to run algorithms and experiments on IBM's quantum processor, work with the individual quantum bits (qubits), and explore tutorials and simulations of what might be possible with quantum computing.
I'll interpret the question as what I do as a computational condensed matter physicist.
It may also be helpful to read Quora User's answer to What is it like to be a theoretical condensed matter physicist?
Building theoretical models
A great deal of my time at work is spent on building theoretical models of condensed matter systems that I am interested in. These models can be quite complicated since I am not constrained by the necessity to solve them on pen and paper. In a sense, I am like an architect designing a building but what I make are a set of equations that I will like to be solved so
I'll interpret the question as what I do as a computational condensed matter physicist.
It may also be helpful to read Quora User's answer to What is it like to be a theoretical condensed matter physicist?
Building theoretical models
A great deal of my time at work is spent on building theoretical models of condensed matter systems that I am interested in. These models can be quite complicated since I am not constrained by the necessity to solve them on pen and paper. In a sense, I am like an architect designing a building but what I make are a set of equations that I will like to be solved so that I can learn something about their physical properties.
Here's are some examples:
Example 1: The model can be a set of equations I need to calculate to get the scattering rates of electrons moving in a crystal. Their solutions are then plugged into another set of equations used to compute their mobility in the solid. This is mostly a number-crunching exercise.
Example 2: I have a set of equations modeling the propagation of lattice waves in solids. The equations however depends on certain statistical correlations which can only be extracted from the output of a molecular dynamics simulation. After these correlations are extracted, I plug them into another program which takes the equations and converts them into meaningful physical quantities.
Solving mathematical models on the computer
I write computer programs to solve these equations. Sometimes, it is necessary to solve the models from scratch. On other occasions, it really just entails modifying an existing program that I have or that is on the shelf. Here, I am more like a structural engineer where I am in charge of building the thing.
There is a lot of coding. However, the choice of language depends on the type of problem. If the problem is one where the underlying mathematical equations needs to be refined or modified frequently, I use Matlab or Python which are more flexible even though they are slow. On the other hand, if the emphasis is on speed and scalability involving huge amounts of memory and if the underlying mathematical model is not going to be changed much, then I may use something like C, C++ or Fortran.
I also sometimes use codes like LAMMPS or Quantum Espresso to calculate parameters that I need to plug into my own code. Some time is spent writing scripts or modules interfacing my own code to these programs. This can be quite frustrating because the documentation for these programs is not as thorough as I will like them to be. Understanding how they work in specific cases requires me to trawl their online help forums. On the rare occasion, I need to modify the program and this usually is very time-consuming because it basically involves reverse-engineering the code. There is also no guarantee that the code won't break if you modify it.
Also, a lot of time is spent waiting for the simulation codes to run on a shared supercomputing cluster. This can take a long time when there are 5,000+ jobs in the queue. When possible, I avoid running codes on the cluster. I have a 12-core workstation, inherited from a colleague who left around the time I joined my current employers, that I use for debugging and running small simulations before I try them on the cluster.
Most of the research work is done on Linux or Unix. However, I have Windows on my office laptop because that I have to run certain Windows-only programs (e.g. Origin Pro, MS Office, EndNote, Adobe Pro, etc). It's somewhat inconvenient but I can live with it.