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Quantum technologies

A hub about quantum calculations

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Quantum Computers Without Math and Philosophy

Reading time 13 min
Views 1.7K

In this article, I will break down all the secrets of quantum computers piece by piece: what superposition (useless) and entanglement (interesting effect) are, whether they can replace classical computers (no) and whether they can crack RSA (no). At the same time, I will not mention the wave function and annoying Bob and Alice that you might have seen in other articles about quantum machines.

The first and most important thing to know is that quantum computers have nothing to do with conventional ones. Quantum computers are analog in nature, they have no binary operations. You have probably already heard about Qubits that they have a state of 0, 1 and 0-1 at the same time and with the help of this feature calculations are very fast: this is a delusion. A qubit is a magnet (usually an atom or an electron) suspended in space, and it can rotate on all three axes. In fact, the rotations of a magnet in space are the operations of a quantum computer. Why can it speed up calculations? It was very difficult to find the answer, but the most patient readers will find it at the end of the article.

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Total votes 8: ↑6 and ↓2 +4
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Quantum Scientists Make Multiple Qubits Team Up to Improve Error-Correction

Reading time 3 min
Views 604

This shows the Bacon–Shor subsystem code implemented on a 15-ion chain.

Multiple heads are better than one in real world calculations. Now, a team of University of Maryland-led quantum engineers report that multiple qubits may be better than one when it comes to error-corrections.

In what’s been described as a foundational step toward using quantum computers to tackle practical problems, the team combined nine qubits — a quantum bit — to make a single, improved logical qubit. A logical qubit can be used to probe for mistakes that extremely sensitive quantum computers are subject to, according to the researchers.

In the paper, which was just published in Nature, the team write that “Although fault-tolerant design works in principle, it has not previously been demonstrated in an error-corrected physical system with native noise characteristics. Here we experimentally demonstrate fault-tolerant circuits for the preparation, measurement, rotation and stabilizer measurement of a Bacon–Shor logical qubit using 13 trapped ion qubits.”

Nine of the qubits were termed data qubits and the four remaining are referred to as ancilla — or extra — qubits. The logical qubit was based on a quantum error correction code to easily detect and correct errors and made it to be fault-tolerant, or minimize the negative effects of errors.

“Qubits composed of identical atomic ions are natively very clean by themselves,” said Christopher Monroe, who is a Fellow of the Joint Center for Quantum Information and Computer Science and a College Park Professor in the Department of Physics at the University of Maryland in a university news release. “However, at some point, when many qubits and operations are required, errors must be reduced further, and it is simpler to add more qubits and encode information differently. The beauty of error correction codes for atomic ions is they can be very efficient and can be flexibly switched on through software controls.”

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The QC House of Cards

Reading time 4 min
Views 696
There’s Gold in Them Thar Hills

Gold rushes can make people crazy. 1848 was enough of an indicator of that. When Sam Brannan announced to the world: ‘Gold! Gold! Gold from the American River!’, half the world’s population (or so it seemed to the tiny California population which lived there at the time) descended on the soon to be the newest state of the union.

San Francisco, before a small hamlet with a few hundred pioneers living there, became a centre of vice, murder and debauchery overnight.

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Two hundred years before tulip mania hit Europe, and like in California with its argonauts or 49ers, it impoverished more than it made rich. In the early 2000s, too, the Dot.Com bubble created a speculative tendency in people when irrationality took over all reason.
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Four Ways Quantum Computing Will Change Artificial Intelligence Forever

Reading time 4 min
Views 1.8K
If science were a dating app, quantum physics and machine learning probably wouldn’t be a match. They’re from completely different fields and often require completely different backgrounds and skills. But, throw in a little quantum computing and, suddenly, that science-matchmaking app becomes Tinder and the attraction between the two is palpable.

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(Credit: cmo.adobe.com/articles/2017/5/how-will-artificial-intelligence-impact-business-tlp-ptr.html#gs.5zlifl)

Even though the extent of change that quantum computing will unleash on AI is up for debate, many experts now more than suspect that quantum computing will definitely alter AI at some level. Analysts from bank holding company BBVA, for example, point toward the natural synergy between quantum computing and AI as reasons why quantum machine learning will eventually best classical machine learning.

“Quantum machine learning can be more efficient than classic machine learning, at least for certain models that are intrinsically hard to learn using conventional computers,” says Samuel Fernández Lorenzo, a quantum algorithm researcher who collaborates with BBVA’s New Digital Businesses area. “We still have to find out to what extent do these models appear in practical applications.”
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Could Quantum Computing Help Reverse Climate Change?

Reading time 4 min
Views 984
The unique powers of quantum computation may give humanity an important weapon — or several weapons — against climate change, according to one quantum computer pioneer.
One of the possible solutions for the excess carbon in the atmosphere and to reach global climate goals is to suck it out. It sounds pretty easy, but, in fact, the technology to do so cheaply and easily isn’t quite here yet, according to Jeremy O’Brien Chief Executive Officer, PsiQuantum, a quantum computing startup.

Currently, there is no way to simulate large complex molecules, like carbon dioxide. Current classical computers cannot simulate these types of molecules because the problem grows exponentially with the size or complexity of the simulated molecules, according to O’Brien, who wrote an article outlining the issue at the World Economic Forum’s annual meeting held recently.

“Crudely speaking, if simulating a molecule with 10 atoms takes a minute, a molecule with 11 takes two minutes, one with 12 atoms takes four minutes and so on,” he writes. “This exponential scaling quickly renders a traditional computer useless: simulating a molecule with just 70 atoms would take longer than the lifetime of the universe (13 billion years).”
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Total votes 5: ↑3 and ↓2 +1
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Scientists Turn a Quantum Computer into a Time Machine — At least, for a Second…

Reading time 5 min
Views 1.8K
Scientists said they were able to return the state of a quantum computer a fraction of a second into the past, according to a university press release. The researchers, who are from the Moscow Institute of Physics and Technology, along with colleagues from the U.S. and Switzerland, also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study came out recently in Scientific Reports.
“This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time: from the past to the future,” commented the study’s lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.

While the researchers don’t expect you to take a trip back to the high school prom just yet, they added that the time reversal algorithm could prove useful for making quantum computers more precise.

“Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors,” Lebedev explained.

The researchers said that the work builds on some earlier work that recently garnered headlines.

“We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell’s demon,” Lesovik said. “The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”
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The World’s Top 12 Quantum Computing Research Universities

Reading time 5 min
Views 3.9K
In just a few years, quantum computing and quantum information theory has gone from a fringe subject offered in small classes at odd hours in the corner of the physics building annex to a full complement of classes in well-funded programs being held at quantum centers and institutes at leading universities.

The question now for many would-be quantum computer students is not, “Are there universities that even offer classes in quantum computing,” but, rather, “Which universities are leaders at quantum computing research.”

We’ll look at some of the best right now:

The Institute for Quantum Computing — University of Waterloo


The University of Waterloo can proudly declare that, while many universities avoided offering quantum computing classes like cat adoption agencies avoided adoption applications from the Schrodinger family, this Canadian university went all in.

And it paid off.
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A Second Year of Q#

Reading time 3 min
Views 978
You can see all of the release notes for the year here.

Remember How We Started


Our first release of our second year, 0.4, was a triumph! we got a customer request for a big integer type on January 1st, and were able to respond by shipping a new BigInt data type just 29 short days later!!! Remember, we’re outside Seattle, pretty far north, so our winter days are really short.

Our secret? We had started working on the BigInt type in December.

We also decided to change our release cadence for our second year of Q#. Our first year, we had shipped releases sporadically, when we had some major feature to share, or possibly just a fix to an annoying bug. For our second year, we moved to a more regular release cadence, putting out a new release every month. We hoped that this would make things more predictable for our users and easier for us to manage.

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Microsoft Q# Coding Contest – Winter 2019

Reading time 3 min
Views 1.7K

Microsoft’s Quantum team is excited to announce the Q# Coding Contest – Winter 2019! In this contest you can put your quantum programming skills to the test, solving quantum computing tasks in Q#. Winners will receive a Microsoft Quantum T-shirt!


Quantum computing is a radically different computing paradigm compared to classical computing. Indeed, it is so different that some tasks that are believed to be classically intractable (such as factoring integers or simulating physical systems) can be performed efficiently on a quantum computer. In 2017 Microsoft introduced the Quantum Development Kit which includes the Q# programming language. Q# can be used with Visual Studio, Visual Studio Code or the command line, on Windows, macOS, and Linux.


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