Category Archives: Quantum Computer
How to defend against quantum computing attacks – ScienceBlog.com – ScienceBlog.com (blog)
The encryption codes that safeguard internet data today wont be secure forever.
Future quantum computers may have the processing power and algorithms to crack them.
Nathan Hamlin, instructor and director of the WSU Math Learning Center, is helping to prepare for this eventuality.
He is the author of a new paper in the Open Journal of Discrete Mathematics that explains how a code he wrote for a doctoral thesis, the Generalized Knapsack Code, could thwart hackers armed with next generation quantum computers.
The paper clarifies misunderstandings about the complex field of public key cryptography and provides a common basis of understanding for the technical experts who will eventually be tasked with designing new internet security systems for the quantum computing age.
Designing security systems to protect data involves experts from many different fields who all work with numbers differently, Hamlin said. You are going to have pure and applied mathematicians, computer programmers and engineers all involved in the process at some point. For it to work in real life, all of these people need to have a common language to communicate so that they can make important decisions about how to safeguard online transactions and personal communications in the future.
Preparing for the future
Quantum computers operate on the subatomic level and theoretically provide processing power that is millions, if not billions of time faster than silicon-based computers. A hacker armed with a next generation quantum computer could in theory decrypt any internet communication that was sent today, Hamlin said.
In order to create an online security system better prepared for future demands, Hamlin and retired mathematics professor William Webb created the Generalized Knapsack Code in 2015 by retrofitting a previous version of the code with alternative number representations that go beyond the standard binary and base 10 sequences todays computer use to operate.
In his paper, Hamlin breaks down how the generalized knapsack code works in terms that computer scientists, engineers and other experts outside the field of pure mathematics can understand. He explains that by disguising data with number strings more complex than the 0s and 1s conventional computers use to operate, the generalized knapsack offers a viable security method for defending against quantum computing hacks.
The Generalized Knapsack Code expands upon the binary representations todays computers use to operate by using a variety of representations other than 0s and 1, Hamlin said. This lets it block a greater array of cyberattacks, including those using basis reduction, one of the decoding methods used to break the original knapsack code.
Hamlin said his hope is that his paper, Number in Mathematical Cryptography, clears up misunderstandings he has run into professionally so that the generalized knapsack code can be developed for future use.
Quantum computing will change how we handle data and we, as a society, are going to have to make some important decisions about how to prepare for it, Hamlin said. A code like this can be implemented on conventional hardware and yet it would also be secure from a hacker with a quantum computer. I think it is time for us to consider this code very seriously for adapting commerce and perhaps communication in light of the possibility of quantum computing.
View original post here:
How to defend against quantum computing attacks - ScienceBlog.com - ScienceBlog.com (blog)
Researchers Have Directly Tested Two Quantum Computing … – Futurism
In Brief
If you arent already, youre likely soon to find yourselflooking forward to the day when quantum computers will replace regular computers for every day use. The computing power ofquantum computersis immense compared to what regular desktops or laptops can do. The downside is, current quantum computing technology are limited by the bulky frameworks and extreme conditions they require in order to function.
Quantum computers need specialized setups in order to sustain and keep quantum bits the heart of quantum computing working. These qubits are particles in a quantum state of superposition, which allows them to encode and transmit information as 0s and 1s simultaneously. Most computers run on binary bit systems which useeither0s or 1s. Sincequantum computers can use both at the same time, they can process more information faster. That being said,Sustaining the life of qubitsis particularly difficult, but researchers are investigating quantum computing studies are trying to find ways to prolong the life of qubits using various techniques.
Now, for the first time ever, two quantum computers have been pitted against one another. One is a chip developed by IBM and used qubits made from superconducting materials. The other is a chip designed by the University of Maryland thatrelies on electromagnetic fields to trap a quantum material called ytterbium ions, which can be harvested forfor its qubits. Although they used different methods, both chips run algorithms the same way and worked with just five qubits.
Because both were still modest in power, the test couldnt really show which had better qubits. While IBMs quantum computer proved to be faster, it was also less reliable. IBMs qubits also broke down much easier than the University of Marylands. The latter had qubits that were interconnected thanks to the nature of ytterbium which made them capable of sharing information with each other. IBMs, on the other hand, needed a central hub to swap information.
Still, it was a valuable experiment, and definitely a sign of improving quantum computing technology. It also stands tohelp researchers figure out which qubit technology would more efficient and viable for further development. For a long time, the devices were so immature that you couldnt really put two five-qubit gadgets next to each other and perform this kind of comparison, said Simon Benjamin, a University of Oxford physicist who wasnt part of the study. Its a sign that this technology is maturing.
Read the original here:
Researchers Have Directly Tested Two Quantum Computing ... - Futurism
Two Quantum Computers Face-Off for the First Time in History! – Interesting Engineering
Supercomputers are about to jump to an entirely new level. Quantum computing is evolving fast, and now, two quantum computers faced off for the first time in history.
[Image Source:Ars Electronica via Flickr]
Earlier this year, researchers at Cornell University pitted two quantumcomputers against each other in an epic virtual battle. The challenge was to perform and solve an algorithm to compare and determine which quantum computer is the most effective. Both computers are state-of-the-art 5-qubit quantum computers which operate on two entirely different platforms.
Despite their differences, the researchers discovered a way to program the computers in such a way that is blind to the operating hardware. The results determined one computer was more reliable, and the other could carry out operations faster.
For a long time, the devices were so immature that you couldnt really put two five-qubit gadgets next to each other and perform this kind of comparison, says Simon Benjamin, a physicist at the University of Oxford in the United Kingdom, who is not affiliated with the study. Its a sign that this technology is maturing.
The two competingcomputers are made from two entirelydifferent setups,making it especiallyintriguing for scientists to test which of the two are better. One computer which belongs to the University of Maryland. Its setup relies on a trapped-ion system.In it, fiveytterbium ions are held in place by a strong electromagnetic trap. The ions are actuated by lasers to carry out the programmed algorithms.
On the other hand is IBMs computer with an entirely different configuration.In contrast, IBMs computer relies on multiple superconducting loops which carry out algorithms using microwave signals. Their computer is also the first one in history to be publically accessible via cloud computing. Its ability to be programmed by online users was the reason the experimentcould be carried out.
Unlike classical computers, quantum computers rely on qubits instead of the more commonly used bit. Traditional computers use transistors which operate in binary- a system which relies on ones and zeros. Quantum bits (or qubits), can represent one, zero, or both one and zero simultaneously- a property better-knownas superposition. Things that exist insuperpositions have an equalprobability of being in multiple positions at a certain time.
The superposition of a quantum computer does not allow the qubits to be explained by the individual part (on or off), but rather, the system as a whole- what is it doing, where it is doing it, and what it needs to do. This is known as entanglement,where one piece of information directly relies on exactly what another bit is doing at that very instant- unlike classical computers where calculations are carried out in a singular train. More complex calculations can be carried out with this new phenomena to re-imagine what computers can do.
In the tests, the computers could carry out operations with varying success. The algorithms which were carried out were completely blind to the underlying hardware. In this experiment, the ion computer maintained a77.1 percent success rate. However, IBMs computer could only operate the same algorithms with 35.1 percentaccuracy. The test confirmed the ion computer is more effective more constantly with the given algorithm. However, IBMs computer can operate faster.
The results were recentlypublishedlast week on arXiv.
Superpositions are incredibly delicate. Simply observing them can ruin their properties entirety. The biggest challenge at the moment is developing a system which can reliably carry out algorithms with precision.
If you have enough coherence, it doesnt matter how long the whole operation of your algorithm might take.
Read the original here:
Two Quantum Computers Face-Off for the First Time in History! - Interesting Engineering
Split decision in first-ever quantum computer faceoff | Science | AAAS – Science Magazine
Ion traps can make for a reliable quantum computer.
S. Debnath and E. Edwards/JQI
By Gabriel PopkinFeb. 21, 2017 , 3:00 AM
In a new study, two quantum computers fashioned from dramatically different technologies have competed head-to-head in an algorithm-crunching exercise. One computer was more reliable, and the other was faster. But whats most important, some scientists say, is that for the first time, two different quantum computers have been compared and tested on the same playing field.
For a long time, the devices were so immature that you couldnt really put two five-qubit gadgets next to each other and perform this kind of comparison, says Simon Benjamin, a physicist at the University of Oxford in the United Kingdom, who was not involved in the study. Its a sign that this technology is maturing.
One of the computers is built around five ytterbium ions held in an electromagnetic trap and manipulated by lasers. It belongs to a lab led by Chris Monroe, a physicist at the University of Maryland in College Park, and co-founder of the startup company ionQ. The other computer belongs to IBM. At its heart are five small loops of superconducting metal that can be manipulated by microwave signals. It is also the worlds only quantum computer that can be programmed online by users, rather than exclusively by scientists in the laba fact that allowed Monroes team to design the experiment.
Neither device has much computing power, but they demonstrate the principle that many think will eventually make quantum computers a major technology. Unlike conventional computers bits, which can be in states of only 0 or 1, quantum computers rely on quantum bits, or qubits, that can be teased into combinations, or superpositions, of both 0 and 1. In Monroes computer, each qubit is an ion in which an electron can be placed at one energy level to signify 0, another to signify 1, or both levels at once. In each of IBMs superconducting circuits, electric current can circulate with one of two different strengths, or at both levels simultaneously. Its also possible to join the superposition states of many qubits. This gives a quantum computer a potential calculating power that grows exponentially with every added bit.
But the states of qubits are also fragile: Small perturbations from the outside world can easily collapse the superpositions to just a 0 or a 1. So computers must carefully maintain superposition states as a computation proceeds. In the test, the two computers both had two-qubit gate fidelities, or probabilities of successfully completing a single two-qubit logical operation, of about 97%considerably below what will ultimately be needed for any real world operation.
IBMs five-qubit chip made of superconducting loops was faster but less reliable than a quantum computer made of ions.
IBM research/flickr
To test their performance, Monroes team ran a set of standard algorithms on each device, and compared the output. The ion computer got the right answer more often in each case. For one particular exercise, the contrast was especially dramatic: The ion computer achieved a 77.1% success rate, whereas the superconducting computer succeeded only 35.1% of the time. The scientistspublished their resultslast week on arXiv.
The performance difference arises not from the qubits themselves, but from how they are wired together, Monroe says. Each of his ions can interact with every other ion, reducing the number of operations needed for many tasksand the chances that a superposition will collapse. In the IBM computer, by contrast, four of the superconducting loops were connected only to one central one, often necessitating additional operations to swap information among the loops. Because no operation is 100% reliable, the overall success rate declines as the number of operations grows. Connectivity matters, Monroe says.
Jerry Chow, a physicist who leads IBMs quantum computing team at the companys Yorktown Heights, New York, lab, acknowledges that connectivity is important. But ultimately, he expects that qubit superposition states will last longer and be more coherentwhich would mean that his computers lower connectivity wont necessarily drag down its overall reliability in the long run. If you have enough coherence, it doesnt matter how long the whole operation of your algorithm might take. He also notes that IBMs online computer now features more qubit connections than it did when Monroes team ran its test, which would likely bring it closer to equaling the ion computers performance. And both labs are already working on more reliable next-generation devices with more qubits.
Indeed, the study compares the embryonic form of the two front-running approaches to quantum computing, Benjamin says. A practical device made of either ions or superconducting loops will need thousands of qubits, and the web of interconnections between them will grow far more complex. He also notes that whereas the ion computer is more reliable at the moment, the superconducting computer is faster. IBMs device completes a two-qubit operation in 250 to 450 nanoseconds, up to 1000 times faster than the ion computer.
The study also provides food for thought for quantum software designers like Krysta Svore, a Microsoft researcher in Redmond, Washington. Understanding how quantum computers specific architectures affect performance will be critical for optimizing future algorithms, she says. Its a great step to start that conversation.
Please note that, in an effort to combat spam, comments with hyperlinks will not be published.
Read more:
Split decision in first-ever quantum computer faceoff | Science | AAAS - Science Magazine