What is Quantum Computers || The Hype Over Quantum Computers, Explained

 

What is Quantum Computers

Even though we experience the benefits of classical computing every day, there are problems above a certain size and complexity that would take a traditional computer an impractical amount of time to solve. Enter quantum computing. All computers rely on a fundamental ability to store and manipulate information. Current computers manipulate individual bits, which store information as binary 0 and 1 states. For example, when our human eyes see the letter "A", our computer sees a specific string of zeroes and ones. From social media to spreadsheets (show examples of classical computer: Word, Excel, social media, video games, etc), everything is done through these sequences of zeroes and ones (matrix style string of bits). Where current computers use bits, quantum computers use qubits.The bits in our current computers can only be either one or zero, but not both. But qubits can represent a one and a zero at the same time. So if computers were coins, current models would be a coin flip with either heads or tails as the only outcomes. But quantum computing would be like spinning the coin; the computer doesn't have to choose one or the other. This allows quantum computers to look at many different variables simultaneously. The good news is that quantum computers would be thousands of times faster than our current computers, possibly reducing the time to solve a complex problem from hundreds of thousands of years to mere seconds. The bad news? Quantum computers are very fragile and need to be perfectly isolated from heat and vibration. One quantum computer is kept cool at 0.015 Kelvin, or about 180 times colder than interstellar space. Although quantum computers promise to power exciting advances such as better batteries or new disease-curing medicines, conventional computers will still be the easiest and most economical solution for tackling most problems.

Quantum Computers Explained – Limits of Human Technology

For most of our history, human technology consisted of our brains, fire, and sharp sticks. While fire and sharp sticks became power plants and nuclear weapons, the biggest upgrade has happened to our brains. Since the 1960's, the power of our brain machines has kept growing exponentially, allowing computers to get smaller and more powerful at the same time. But this process is about to meet its physical limits. Computer parts are approaching the size of an atom. To understand why this is a problem, we have to clear up some basics. A computer is made up of very simple components doing very simple things. Representing data, the means of processing it, and control mechanisms. Computer chips contain modules, which contain logic gates, which contain transistors. A transistor is the simplest form of a data processor in computers, basically a switch that can either block, or open the way for information coming through. This information is made up of bits which can be set to either 0 or 1. Combinations of several bits are used to represent more complex information. Transistors are combined to create logic gates which still do very simple stuff. For example, an AND Gate sends an output of 1 if all of its inputs are 1, and a output of 0 otherwise. Combinations of logic gates finally form meaningful modules, say, for adding two numbers. Once you can add, you can also multiply, and once you can multiply, you can basically do anything. Since all basic operations are literally simpler than first grade math, you can imagine a computer as a group of 7-year-olds answering really basic math questions. A large enough bunch of them could compute anything from astrophysics to Zelda. However, with parts getting tinier and tinier, quantum physics are making things tricky. In a nutshell, a transistor is just an electric switch. Electricity is electrons moving from one place to another. So, a switch is a passage that can block electrons from moving in one direction. Today, a typical scale for transistors is 14 nanometers, which is about 8 times less than the HIV virus' diameter, and 500 times smaller than a red blood cell. As transistors are shrinking to the size of only a few atoms, electrons may just transfer themselves to the other side of a blocked passage via a process called Quantum Tunneling. In the quantum realm, physics works quite differently from the predictable ways we're used to, and traditional computers just stop making sense. We are approaching a real physical barrier for our technological progress. To solve this problem, scientists are trying to use these unusual quantum properties to their advantage by building quantum computers. In normal computers, bits are the smallest unit of information. Quantum computers use qubits which can also be set to one of two values. A qubit can be any two level quantum system, such as a spin and a magnetic field, or a single photon. 0 and 1 are this system's possible states, like the photons horizontal or vertical polarization. In the quantum world, the qubit doesn't have to be just one of those, it can be in any proportions of both states at once. This is called superposition. But as soon as you test its value, say, by sending the photon through a filter, it has to decide to be either vertically or horizontally polarized. So as long as it's unobserved, the qubit is in a superposition of probabilities for 0 and 1, and you can't predit which it'll be. But the instant you measure it, it collapses into one of the definite states. Superposition is a game changer. Four classical bits can be in one of two to the power of four different configurations at a time. That's 16 possible combinations, out of which you can use just one. Four qubits in superposition, however, can be in all of those 16 combinations at once. This number grows exponentially with each extra qubit. Twenty of them can already store a million values in parallel. A really weird and unintuitive property qubits can have is Entanglement, a close connection that makes each of the qubits react to a change in the other's state instantaneously, no matter how far they are apart. This means when measuring just one entangled qubit, you can directly deduce properties of it's partners without having to look. Qubit Manipulation is a mind bender as well. A normal logic gate gets a simple set of inputs and produces one definite output. A quantum gate manipulates an input of superpositions, rotates probabilities, and produces another superposition as its output. So a quantum computer sets up some qubits, applies quantum gates to entangle them and manipulate probabilities, then finally measures the outcome, collapsing superpositions to an actual sequence of 0s and 1s. What this means is that you get the entire lot of calculations that are possible with your setup, all done at the same time. Ultimately, you can only measure one of the results and it'll only probably be the one you want, so you may have to double check and try again. But by cleverly exploiting superposition and entanglement, this can be exponentially more efficient than would ever be possible on a normal computer. So, while quantum computers will not probably not replace our home computers, in some areas, they are vastly superior. One of them is database searching. To find something in a database, a normal computer may have to test every single one of its entries. Quantum computers algorithms need only the square root of that time, which for large databases, is a huge difference The most famous use of quantum computers is ruining IT security. Right now, your browsing, email, and banking data is being kept secure by an encryption system in which you give everyone a public key to encode messages only you can decode. The problem is that this public key can actually be used to calculate your secret private key. Luckily, doing the necessary math on any normal computer would literally take years of trial and error. But a quantum computer with exponential speed-up could do it in a breeze. Another really exciting new use is simulations. Simulations of the quantum world are very intense on resources, and even for bigger structures, such as molecules, they often lack accuracy. So why not simulate quantum physics with actual quantum physics? Quantum simulations could provide new insights on proteins that might revolutionize medicine. Right now, we don't know if quantum computers will be just a specallized tool, or a big revolution for humanity. We have no idea where the limits of technology are, and there's only one way to find out.

 Hype Over Quantum Computers, Explained

Quantum computers use the natural world to produce machines with staggeringly powerful processing potential. I think it's gonna be the most important computing technology of this century, which we are really just about one fifth into. We could use quantum computers to simulate molecules, to build new drugs and new materials and to solve problems plaguing physicists for decades. Wall Street could use them to optimize portfolios, simulate economic forecasts and for complex risk analysis. Quantum computing could also help scientists speed up discoveries in adjacent fields like machine learning and artificial intelligence. Amazon, Google, IBM and Microsoft, plus a host of smaller companies such as Rigetti and D-Wave, are all betting big on Quantum. If you were a billionaire, how many of your billion would you give over for an extra 10 years of life? There are some simply astonishing financial opportunities in quantum computing. This is why there's so much interest. Even though it's so far down the road. But nothing is ever a sure thing. And dealing with the quirky nature of quantum physics creates some big hurdles for this nascent technology. From the very beginning, it was understood that building a useful quantum computer was going to be a staggeringly hard engineering problem if it was even possible at all. And there were even distinguished physicists in the 90s who said this will never work. Is Quantum truly the next big thing in computing, or is it destined to become something more like nuclear fusion? Destined to always be the technology of the future, never the present. In October 2019, Google made a big announcement. Google said it had achieved quantum supremacy. That's the moment when quantum computers can beat out the world's most powerful supercomputers for certain tasks. They have demonstrated with a quantum computer that it can perform a computation in seconds. What would take the world's fastest supercomputer? Years, thousands of years to do that same calculation. And in the field, this is known as quantum supremacy and it's a really important milestone. Google used a 53 qubit processor named Sycamore to complete the computation, a completely arbitrary mathematical problem with no real world application. The Google Quantum computer spit out an answer in about 200 seconds. It would have taken the world's fastest computer around 10000 years to come up with a solution, according to Google scientists. With that, Google claimed it had won the race to quantum supremacy. But IBM had an issue with the findings. Yes, IBM, the storied tech company that helped usher in giant mainframes and personal computing. It's a major player in quantum computing. IBM said one of its massive supercomputer networks, this one at the Oak Ridge National Laboratories in Tennessee, could simulate a quantum computer and theoretically solve the same problem in a matter of days, not the 10000 years that Google had claimed. Either way, it was a huge milestone for quantum computers, and Silicon Valley is taking notice. Venture capital investors are pouring hundreds of millions of dollars into quantum computing startups, even though practical applications are years or even decades away by 2019. Private investors have backed at least 52 quantum technology companies around the world since 2012, according to an analysis by nature. Many of them were spun out of research teams at universities in 2017 and 2018. Companies received at least $450 million in private funding more than four times the funding from the previous two years. That's nowhere near the amount of funding going into a field like artificial intelligence. About $9.3 billion with a venture capital money poured into AI firms in 2018. But the growth in quantum computing funding is happening quickly for an industry without a real application. Yet it is not easy to figure out how to actually use a quantum computer to do something useful. So nature gives you this very, very bizarre hammer in the form of these this interference effect among all of these amplitudes. Right. And it's up to us as quantum computer scientists to figure out what nails that hammer can hit. That's leading to some backlash against the hype and concern that quantum computing could soon become a bubble and then dry up just as fast if progress stalls. Quantum computers are also notoriously fickle. They need tightly controlled environments to operate in. Changes in nearby temperatures and electromagnetic waves can cause them to mess up. And then there's the temperature of the quantum chips themselves. They need to be kept at temperatures colder than interstellar space, close to absolute zero. One of the central tenets of quantum physics is called superposition. That means a subatomic particle like an electron can exist in two different states at the same time. It was and still is super hard for normal computers to simulate quantum mechanics because of superposition. No, it was only in the early eighties that a few physicists, such as Richard Feynman had the amazing suggestion that if nature is giving us that computational lemon, well, why not make it into lemonade? You've probably heard or read this explanation of how a quantum computer works. Regular or classical computers run on bits. Bits can either be a 1 or a zero. Quantum computers, on the other hand, run on quantum bits or cubits. Cubits can be either 1 or zero or both or a combination of the two at the same time. That's not wrong per say, but it only scratches the surface. According to Scott Aaronson, who teaches computer science and quantum computing at the University of Texas in Austin. We asked him to explain how quantum computing actually works. Well, let me start with this. You never hear your weather forecaster say we know there's a negative 30 percent chance of rain tomorrow. Right. That would just be non-sense, right? Did the chance of something happening, as always, between 0 percent and 100 percent. But now quantum mechanics is based on numbers called amplitudes. Amplitudes can be positive or negative. In fact, they can even be complex numbers involving the square root of negative one. So so a qubit is a bit that has an amplitude for being zero and another amplitude for being one. The goal for quantum computers is to make sure the amplitudes leading to wrong answers cancel each other out. And it scientists reading the output of the quantum computers are left with amplitudes leading to the right answer of whatever problem they're trying to solve. So what does a quantum computer look like in the real world? The quantum computers developed by companies such as Google, IBM and Rigetti were all made using a process called superconducting And this is where you have a chip the size of an ordinary computer chip and you have little coils of wire in the chip, you know, which are actually quite enormous by the standards of cubits. There are, you know, nearly big enough to see with the naked eye. But you can have two different quantum states of current that are flowing through these coils that correspond to a zero or a one. And of course, you can also have super positions of the two. Now the coil can interact with each other via something called Josef's injunctions. So they're laid out in roughly a rectangular array and the nearby ones can talk to each other and thereby generate these very complicated states, what we call entangled states, which is one of the essentials of quantum computing and the way that the cubists interact with each other is fully programmable. OK. So you can send electrical signals to the chip to say which cube it should interact with each other ones at which time. Now the order for this to work, the whole chip is placed in that evolution refrigerator. That's the size of a closet roughly. And the calls it do about one hundredth of a degree above absolute zero. That's where you get the superconductivity that allows these bits to briefly behave as cubits. And IBM's research lab in Yorktown Heights, New York, the big tech company, houses several quantum computers already hooked up to the cloud. Corporate clients such as Goldman Sachs and JP Morgan are part of IBM's Q Network, where they can experiment with the quantum machines and their programming language. So far, it's a way for companies to get used to quantum computing rather than make money from it. Quantum computers need exponentially more cubits before they start doing anything useful. IBM recently unveiled a fifty three cubic computer the same size as Google's sycamore processor. We think we're actually going to need tens of thousands, hundreds of thousands of qubits to get to real business problems. So you can see quite a lot of advances and doubling every year or perhaps even a little faster is what we need to get us there. That's why it's 10 years out, at least. Quantum computing would need to see some big advances between then and now, bigger advances than what occurred during the timeline of classical computing and Moore's Law. Oh, we need better than Moore's Law. Moore's Law is doubling every two years. We're talking doubling every year. And occasionally some really big jumps. So what's quantum computers become useful? What can they do? Scientists first came up with the idea for quantum computers as a way to better simulate quantum mechanics. That's still the main purpose for them. And it also holds the most moneymaking potential. So one example is the caffeine molecule. Now, if you're like me, you've probably ingested billions or trillions of. Caffeine molecules so far today. Now, if computers are really that good, really that powerful. We have these these tremendous supercomputers that are out there. We should be able to really take a molecule and represented exactly in a computer. And this would be great for many fields, health care, pharmaceuticals, creating new materials, creating new flavorings anywhere where molecules are in play. So if we just start with this basic idea of caffeine, it turns out it's absolutely impossible to represent one simple little caffeine molecule in a classical computer because the amount of information you would need to represent it, the number of zeros and ones you would need is around ten to forty eight. Now, that's a big number. That's one with forty eight zeros following it. The number of atoms in the earth are about 10 to 100 times that number. So in the worst case, one caffeine molecule could use 10 percent of all the atoms in the earth just for storage. That's never going to happen. However, if we have a quantum computer with one hundred and sixty cubits and this is a model of a 50 kubert machine behind me, you can kind of figure, well, if we make good progress, eventually we'll get up to 160 good cubits. It looks like we'll be able to do something with caffeine, a quantum computer, and it's never going to be possible. Classical computer and other potential use comes from Wall Street. Complex risk analysis and economic forecasting. Quantum computing also has big potential for portfolio optimization. Perhaps the biggest business opportunity out of quantum computing in the short term is simply preparing for the widespread use of them. Companies and governments are already attempting to quantum proof their most sensitive data and secrets. In 1994, a scientist at Bell Labs named Peter Shaw came up with an algorithm that proved quantum computers could factor huge numbers much more quickly than their classical counterparts. That also means quantum computers is powerful and efficient enough could theoretically break RSA encryption. RSA is the type of encryption that underpins the entire internet. Quantum computers, the way they're built now, would need millions of cubits to crack RSA cryptography. But that milestone could be 20 or 30 years away and governments and companies are beginning to get ready for it. For a lot of people, that doesn't matter. But for example, for health records, if health records to be opened up that could compromise all kinds of things. Government communications. Banking records. Sometimes even banking records from decades ago contain important information that you don't want exposed. But the problem we've got is we don't really know when we'll be able to do this or even if we'll ever build one big enough to do this. But what we do now, is that if you don't update your cryptography now, all the messages you send over the next few years and the ones in history could potentially be read. What this means, for example, is if you're a Cisco selling networking equipment, you're going to offer quantum-safe encryption as an option in the very near future. Becayse even though it doesn't look like you need it right away. If your product doesn't have it and a competitor does, guess which product gets bought? One big issue facing quantum computing, other than increasing the number of cubits while keeping things stable, is that no one actually knows the best way to build a quantum computer. Yet the Quantum computers, a Google of IBM and other companies show off are very much still experiments. There's also a big education gap. Not many people are studying quantum computing yet. China is pouring billions into quantum computing education, and the U.S. Congress passed a law in 2018 called the National Quantum Initiative Act in order to help catch up watching people get rid of him. Which means that you want to invest in them now. You want to be hiring people with quantum computing knowledge. Not necessarily to do quantum computing, but because you want that intelligence in your organisation so you can take advantage of it when it shows up. Now China, with its promised $10 billion in it, is really upping stakes in terms of the number of Chinese quantum physics PhDs that are going to start appearing. And you know if that hair restoration or life extension drug happens to be property of the Chinese government, what does that do to the world economy? That's much more powerful than making war Other experts have compared Google's announcement to Sputnik, the Soviet satellite launched into orbit in 1957. The beach ball sized satellite was the first manmade object to orbit the Earth. But Sputnik didn't really do anything useful other than prove launching something into space was possible. Many people are surprised that where exactly we are. For those who are just getting started, they like to make noise about vacuum tubes and Sputnik and things like this. But let me give you some numbers. IBM has had quantum computers on the cloud for three and a half years since May of 2016. We're not in any sort of Sputnik error. We're not landing on the moon. But for those of you who like space history, I think we're probably well into Mercury or Gemini.

What is a quantum computer used for?

 Quantum computers are machines that use the properties of quantum physics to store data and perform computations. This can be extremely advantageous for certain tasks where they could vastly outperform even our best supercomputers.

Does NASA have a quantum computer?

In a partnership with Google and independent, nonprofit research corporation Universities Space Research Association (USRA), Ames has established the Quantum Artificial Intelligence Laboratory (QuAIL) at its NASA Advanced Supercomputing (NAS) facility. The laboratory houses a 512-qubit D-Wave Two™ quantum computer.

What is quantum computing in simple terms?

Quantum computing is the study of how to use phenomena in quantum physics to create new ways of computing. Quantum computing is made up of qubits. Unlike a normal computer bit, which can be 0 or 1, a qubit can be either of those, or a superposition of both 0 and 1.

What is the difference between a quantum computer and a regular computer?

What is a quantum computer and how does it differ from classical computers? ... It's not using zeros and ones like classical computers are – bits and bytes – but it is actually able to work with something called qubits. 'Qubits are quantum bits, and have the special property that at the same time they can be zero and one.

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