 Hello and welcome to NewsClick. A recently leaked research paper of Google made the claim that Google has achieved quantum supremacy through its quantum computer, C.Camor. To talk more about this, we have with us Prabir Pukhayastha. So, Prabir, first can you tell us more about what this quantum computer, C.Camor was able to achieve, what does quantum supremacy mean? And does this mean we are in a new age of computing? Well, we certainly in the age of new age of computing as well, but it is not that all the old computers now we have to throw away. It is not that vacuum tubes are superseded by transistors, then by what would be called solid state devices, that is not what is happening. We have a different class of computers which have now come into being, what is we called quantum computers and quantum supremacy is a very narrow and restricted definition. All it means is that quantum computer should be able to do one computation, one computation for a specifically designed problem, which is faster than what a classical computer can do and it has shown yes it can do so, it is a 53 qubit and we will talk about what a qubit is as opposed to a bit, qubit computer, the Google C.Camor and it has computed a specific problem in about 200 seconds, which took take a classical supercomputer, a supercomputer working on classical physics, it would take 10,000 years. So, that yes, in this sense quantum supremacy has been satisfied because that is all it was designed to be, one problem to be solved faster than a supercomputer and a specifically designed problem. But of course, is a huge set of technical challenges doing even this kind of test and this is the first test that a quantum computer is passed doing this kind of computation. So, I think a huge step yes, showing that quantum computers are possible, but what class of problem they will solve, that is still an open issue and when we wear and when can we apply them and what kind of environment will do need and can it be something that we can put in our rooms and around our wrists, carry in our pockets, which you do for all computers as we know that the cell for today is more powerful than what used to be considered an almost a supercomputer say the 20, 25 years back. So, I think those are the kind of issues that we need to address. So, what is the difference between a quantum computer and a classical computer in terms of the way they are built, the way they function? It is a good question and I am not sure that I or anybody can answer that question very easily, because as Feynman said, we do not understand what really the quantum world is. The physics of the quantum world is not something we can understand because we are not in the quantum world. We are in our world which takes over from the atomic atom and outward, so to say. So, the quantum effects which are really some atomic effects are not realized, we do not understand what it is because we are not in that world. So, the quantum world as we now know has a lot of properties which are not what we shall we say not really explicable to us because we cannot have those properties in our world. One is the principle of what is called superposition that an electron can be in two states apparently simultaneously unless it is measured. When it is measured, it is only in one state, it collapses to one state or the other. When it is not measured which is not observed in the terms of quantum mechanics or it can be in either up state or down state which means it could be in two states. In fact, the argument is it is in both states and it only when it is observed the states collapse to one. Now, we are not going to get into what this is because it is not about quantum mechanics but what it does for a quantum computer. The second phenomena which has also been well known which is what is called entanglement that two electrons are entangled with each other in a way that even if they separate it at a distance they still continue to be entangled and the share shall we say opposite properties. If one is up the other one will be down. So, complementarity will be shared across these two electrons which are entangled. Now, this is also what is used. So, we get what are what would we call bits in the computing world instead of that in the quantum world you would call them qubits which therefore have these properties of superposition and entanglement. And this allows you as Feynman and Professor Feynman had predicted this allows you to set up problems which classical computers cannot solve because they need to deal with very large numbers of probabilities and dealing them with the classical world means very long computations. It could be in this case 10,000 years was the calculation that was supposed to be if it was a classical computer. But because the quantum world is probabilistic and the qubits therefore deal with the probabilistic world inherently therefore they have the ability to compute these things much faster. And the interesting part is as you go up qubits number of qubits increase your computational power increases exponentially and therefore you have the ability to crack very large problems in a short phase of time. So, there are three problems that the quantum computer is really faced what is what is called classical error correction. We know that computers need error correction and you need to check errors. So, how does errors propagate? The second was will it last for enough time? So, this was the second issue and the third was was there a credible problem which could be solved and we know the answer is correct. So, the third one is being checked out is the answer being corrected super computers are being used to check the results. But the other two tests it is passed it is shown yes it could be done for 200 seconds and it seems error correction did work and they did have error correction in the 53 qubit machine which Google has produced. So, I think we would say we are two and a half times sure that it is okay we need it to have a number of three all these three conditions satisfied to say yes it is true. But it looks like that the third condition that it is that it was the correct answer is also probably true and the reason that the paper probably has not been published as yet is they are waiting to verify the results before the publish it. So, that it is it is going to obviously come in the major science journal but that is the reason it is beheaded up. So, I would say yes in the narrow definition of quantum supremacy this Google has shown and of course there are lot of other companies in the race but it has shown and I think it is a very significant achievement because it shows yes quantum computers can really solve problems. The sort of threats quantum computing poses to the kind of digital security measures we have in place right now. So, can you tell us about that? Well, there is somebody called Professor Shor who so showed that essentially what we have as the most common cryptographic measure the public private key that you have two very large numbers prime numbers which you multiply and while if you have the keys if you don't have the keys it is difficult to crack it by just looking at the number and using brute force methods. So, the question the answer was to put the public key in a key in public domain and retain your private key and then when people would send you after coding it using your public key would send you the message you could factor it because you had the private key. This kind of encryption Shor had shown quantum computing will crack. But we are not there yet let us be very clear that what we have seen as a particular problem which has been solved this is not Shor's algorithm and even if the Shor's algorithms or other algorithms are found to break this it looks like it could be decades away it could be five years away we don't know but at the moment it doesn't look like this cryptography is under threat as it is being talked about but yes in a some future date we don't know when this cryptography is going to fail that is almost sure. So, we have to move to more secure cryptographic measures which are quantum hack proof and those are being worked on at the moment. So, your entire digital infrastructure the internet protocols will be built on those rather than the current cryptographic measures. But you know I would also still leave one danger that we would have it is that existing whatever we have encrypted which is available today because people think that if it is encrypted it can be public nobody can really read it. Those all those documents will then be readable. So, whatever is currently encrypted if it is available that they all this will become publicly available in uncrypted form and there are dangers therefore of the Bitcoin blockchain kind of systems which cannot retrospectively now recode their cryptographic algorithm. So, I think this does pose a real problem from Bitcoin kind of systems which anyway have never been real money but have been something else. So, I think those kind of systems are definitely at risk therefore yes some things will be at risk but fortunately most of the things we deal with and as you know secrets are no longer secrets after 20 years those hopefully will not have major repercussions but certainly the cryptographic world is going to change in the near in the future we do not know in the near future or decades in the future that is an open question. And finally what are the challenges in the development of quantum computers and where do we where do different countries stand in achieving the development of quantum computers? Let us put it there are various aspects of quantum applications of quantum computers and the larger issue of how to apply quantum effect itself. So, you have quantum communication you have quantum devices these are also being worked on they share certain similarities but they are not identical to quantum computers. So, you are really talking about a whole field which has to advance not just quantum computers. So, you have to invest in this entire field of physics and its applications in terms of technology. So, I think quantum technology if it has to advance it needs money it needs people and you cannot have people unless you have an infrastructure because you are dealing with some almost near zero temperatures within which this quantum computers are created and this qubits exist that also for a brief period of time. So, you are really talking about technological advances and huge investments in technology in order to have either the quantum effects be visible or quantum computers do competitions or you have quantum communication which is secure communication and which Chinese seem to have shown. So, all of this needs as I said capital and human beings. So, if you take money at the moment China and the US are far ahead they are investing in the excess of last 2 to 2 or 2 and a half years 3 years both of them have been spending roughly the amount of 10 billion dollars to 12 billion dollars each of these countries. All others you take European Union put together put we probably somewhere near 1 billion 1.5 billion in the same period. So, about 10 to 15% of what each China and the United States is spending India spending just about 1% of that we have an 80 crore programs 110 million dollars roughly and that spent over 3 years. So, that is really nothing we have a 3 qubit machine at the moment. China has shown a 24 qubit machine the US 50, 60, 70 they are talking about that range. So, we are really way behind. So, not even at the moment we are not even in the race forget about being in there. So, I think it is something which at the moment seems to be a 2 horse race between China and the United States. The United States is still ahead in terms of functional qubit sized devices with China is producing more papers and is also seems to be also having more patents and they have a broader focus in quantum communication they seem to be more advanced than what the US has done. So, if you put all of it together I will say at the moment it seems to be a 2 horse race and if countries like India want to be even remotely in the race then the kind of money we are spending and the kind of infrastructure we have is not even sufficient to have a toe in the door. So, I think that is something that we have to think about do we want to be in the game or shall we decide that we are not in the game we will align with one or the other by the technology which the government seems to believe that it can do and then be dependent on others forever. So, thank you Prabir for joining us for this discussion and that is all the time we have today. Thank you for watching NewsClip.