(Roughly) Daily

Posts Tagged ‘quantum computing

“If you are not completely confused by quantum mechanics, you do not understand it”*…

 

uchicagoscie

 

If we can harness it, quantum technology promises fantastic new possibilities. But first, scientists need to coax quantum systems to stay yoked for longer than a few millionths of a second.

A team of scientists at the University of Chicago’s Pritzker School of Molecular Engineering announced the discovery of a simple modification that allows quantum systems to stay operational—or “coherent”—10,000 times longer than before. Though the scientists tested their technique on a particular class of quantum systems called solid-state qubits, they think it should be applicable to many other kinds of quantum systems and could thus revolutionize quantum communication, computing and sensing…

Down at the level of atoms, the world operates according to the rules of quantum mechanics—very different from what we see around us in our daily lives. These different rules could translate into technology like virtually unhackable networks or extremely powerful computers; the U.S. Department of Energy released a blueprint for the future quantum internet in an event at UChicago on July 23. But fundamental engineering challenges remain: Quantum states need an extremely quiet, stable space to operate, as they are easily disturbed by background noise coming from vibrations, temperature changes or stray electromagnetic fields.

Thus, scientists try to find ways to keep the system coherent as long as possible…

“This breakthrough lays the groundwork for exciting new avenues of research in quantum science,” said study lead author David Awschalom, the Liew Family Professor in Molecular Engineering, senior scientist at Argonne National Laboratory and director of the Chicago Quantum Exchange. “The broad applicability of this discovery, coupled with a remarkably simple implementation, allows this robust coherence to impact many aspects of quantum engineering. It enables new research opportunities previously thought impractical.”…

Very big news at a very small scale: “Scientists discover way to make quantum states last 10,000 times longer.”

*John Wheeler

###

As we strive for stability, we might send calculated birthday greetings to Brook Taylor; he was born on this date in 1685.  A mathematician, he is best known for his work in describing and understanding oscillation.  In 1708, Taylor produced a solution to the problem of the center of oscillation.  His Methodus incrementorum directa et inversa (“Direct and Indirect Methods of Incrementation,” 1715) introduced what is now called the calculus of finite differences.  Using this, he was the first to express mathematically the movement of a vibrating string on the basis of mechanical principles.  Methodus also contained Taylor’s theorem, later recognized by Joseph Lagrange as the basis of differential calculus.

A gifted artist, Taylor also wrote on the basic principles of perspective, including the first general treatment of the principle of vanishing points.

220px-BTaylor source

 

 

“Moore’s Law is really a thing about human activity, it’s about vision, it’s about what you’re allowed to believe”*…

 

Karen-fungal-computing-2

 

In moments of technological frustration, it helps to remember that a computer is basically a rock. That is its fundamental witchcraft, or ours: for all its processing power, the device that runs your life is just a complex arrangement of minerals animated by electricity and language. Smart rocks. The components are mined from the Earth at great cost, and they eventually return to the Earth, however poisoned. This rock-and-metal paradigm has mostly served us well. The miniaturization of metallic components onto wafers of silicon — an empirical trend we call Moore’s Law — has defined the last half-century of life on Earth, giving us wristwatch computers, pocket-sized satellites and enough raw computational power to model the climate, discover unknown molecules, and emulate human learning.

But there are limits to what a rock can do. Computer scientists have been predicting the end of Moore’s Law for decades. The cost of fabricating next-generation chips is growing more prohibitive the closer we draw to the physical limits of miniaturization. And there are only so many rocks left. Demand for the high-purity silica sand used to manufacture silicon chips is so high that we’re facing a global, and irreversible, sand shortage; and the supply chain for commonly-used minerals, like tin, tungsten, tantalum, and gold, fuels bloody conflicts all over the world. If we expect 21st century computers to process the ever-growing amounts of data our culture produces — and we expect them to do so sustainably — we will need to reimagine how computers are built. We may even need to reimagine what a computer is to begin with.

It’s tempting to believe that computing paradigms are set in stone, so to speak. But there are already alternatives on the horizon. Quantum computing, for one, would shift us from a realm of binary ones and zeroes to one of qubits, making computers drastically faster than we can currently imagine, and the impossible — like unbreakable cryptography — newly possible. Still further off are computer architectures rebuilt around a novel electronic component called a memristor. Speculatively proposed by the physicist Leon Chua in 1971, first proven to exist in 2008, a memristor is a resistor with memory, which makes it capable of retaining data without power. A computer built around memristors could turn off and on like a light switch. It wouldn’t require the conductive layer of silicon necessary for traditional resistors. This would open computing to new substrates — the possibility, even, of integrating computers into atomically thin nano-materials. But these are architectural changes, not material ones.

For material changes, we must look farther afield, to an organism that occurs naturally only in the most fleeting of places. We need to glimpse into the loamy rot of a felled tree in the woods of the Pacific Northwest, or examine the glistening walls of a damp cave. That’s where we may just find the answer to computing’s intractable rock problem: down there, among the slime molds…

It’s time to reimagine what a computer could be: “Beyond Smart Rocks.”

(TotH to Patrick Tanguay.)

* “Moore’s Law is really a thing about human activity, it’s about vision, it’s about what you’re allowed to believe. Because people are really limited by their beliefs, they limit themselves by what they allow themselves to believe about what is possible.”  – Carver Mead

###

As we celebrate slime, we might send fantastically far-sighted birthday greetings to Hugo Gernsback, a Luxemborgian-American inventor, broadcast pioneer, writer, and publisher; he was born on this date in 1884.

Gernsback held 80 patents at the time of his death; he founded radio station WRNY, was involved in the first television broadcasts, and is considered a pioneer in amateur radio.  But it was as a writer and publisher that he probably left his most lasting mark:  In 1926, as owner/publisher of the magazine Modern Electrics, he filled a blank spot in his publication by dashing off the first chapter of a series called “Ralph 124C 41+.” The twelve installments of “Ralph” were filled with inventions unknown in 1926, including “television” (Gernsback is credited with introducing the word), fluorescent lighting, juke boxes, solar energy, television, microfilm, vending machines, and the device we now call radar.

The “Ralph” series was an astounding success with readers; and later that year Gernsback founded the first magazine devoted to science fiction, Amazing Stories.  Believing that the perfect sci-fi story is “75 percent literature interwoven with 25 percent science,” he coined the term “science fiction.”

Gernsback was a “careful” businessman, who was tight with the fees that he paid his writers– so tight that H. P. Lovecraft and Clark Ashton Smith referred to him as “Hugo the Rat.”

Still, his contributions to the genre as publisher were so significant that, along with H.G. Wells and Jules Verne, he is sometimes called “The Father of Science Fiction”; in his honor, the annual Science Fiction Achievement awards are called the “Hugos.”

(Coincidentally, today is also the birthday– in 1906– of Philo T. Farnsworth, the man who actually did invent television… and was thus the inspiration for the name “Philco.”)

[UPDATE- With thanks to friend MK for the catch:  your correspondent was relying on an apocryphal tale in attributing the Philco brand name to to Philo Farnsworth.  Farsworth did work with the company, and helped them enter the television business.  But the Philco trademark dates back to 1919– pre-television days– as a label for what was then the Philadelphia Storage Battery Company.]

Gernsback, wearing one of his inventions, TV Glasses

source

 

 

“A classical computation is like a solo voice—one line of pure tones succeeding each other. A quantum computation is like a symphony—many lines of tones interfering with one another.”*…

 

abstractions-a-419

 

Quantum computers will never fully replace “classical” ones like the device you’re reading this article on. They won’t run web browsers, help with your taxes, or stream the latest video from Netflix.

What they will do—what’s long been hoped for, at least—will be to offer a fundamentally different way of performing certain calculations. They’ll be able to solve problems that would take a fast classical computer billions of years to perform. They’ll enable the simulation of complex quantum systems such as biological molecules, or offer a way to factor incredibly large numbers, thereby breaking long-standing forms of encryption.

The threshold where quantum computers cross from being interesting research projects to doing things that no classical computer can do is called “quantum supremacy.” Many people believe that Google’s quantum computing project will achieve it later this year…

Researchers are getting close to building a quantum computer that can perform tasks a classical computer can’t. Here’s what the milestone will mean: “Quantum Supremacy Is Coming: Here’s What You Should Know.”

* Seth Lloyd, Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos

###

As we get weird, we might recall that it was on this date in 2012 that Ohioan Beth Johnson attempted to break a record that has been set in on this same date 1999 by a group of English college students– for the largest working yoyo in the world.  The British yoyo was 10 feet in diameter; hers, 11 feet, 9 inches.  (It weighed 4,620 lbs.)  Her attempt on this date failed, as did another.  But finally, in September, 2012, she was able successfully to deploy it from a crane in Cincinnati… and earn her way into the Guinness Book of World Records

ss-140909-guinness-08.fit-660w

Beth Johnson and her record-setting creation

source

 

“As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.”*…

 

quantum computing

Quantum computing is all the rage. It seems like hardly a day goes by without some news outlet describing the extraordinary things this technology promises. Most commentators forget, or just gloss over, the fact that people have been working on quantum computing for decades—and without any practical results to show for it.

We’ve been told that quantum computers could “provide breakthroughs in many disciplines, including materials and drug discovery, the optimization of complex manmade systems, and artificial intelligence.” We’ve been assured that quantum computers will “forever alter our economic, industrial, academic, and societal landscape.” We’ve even been told that “the encryption that protects the world’s most sensitive data may soon be broken” by quantum computers. It has gotten to the point where many researchers in various fields of physics feel obliged to justify whatever work they are doing by claiming that it has some relevance to quantum computing.

Meanwhile, government research agencies, academic departments (many of them funded by government agencies), and corporate laboratories are spending billions of dollars a year developing quantum computers. On Wall Street, Morgan Stanley and other financial giants expect quantum computing to mature soon and are keen to figure out how this technology can help them.

It’s become something of a self-perpetuating arms race, with many organizations seemingly staying in the race if only to avoid being left behind. Some of the world’s top technical talent, at places like Google, IBM, and Microsoft, are working hard, and with lavish resources in state-of-the-art laboratories, to realize their vision of a quantum-computing future.

In light of all this, it’s natural to wonder: When will useful quantum computers be constructed? The most optimistic experts estimate it will take 5 to 10 years. More cautious ones predict 20 to 30 years. (Similar predictions have been voiced, by the way, for the last 20 years.) I belong to a tiny minority that answers, “Not in the foreseeable future.” Having spent decades conducting research in quantum and condensed-matter physics, I’ve developed my very pessimistic view. It’s based on an understanding of the gargantuan technical challenges that would have to be overcome to ever make quantum computing work…

Michel Dyakonov makes “The Case Against Quantum Computing.”

* Albert Einstein

###

As we feel the need for speed, we might recall that it was on this date in 1942 that a team of scientists led by Enrico Fermi, working inside an enormous tent on a squash court under the stands of the University of Chicago’s Stagg Field, achieved the first controlled nuclear fission chain reaction… laying the foundation for the atomic bomb and later, nuclear power generation.

“…the Italian Navigator has just landed in the New World…”
– Coded telephone message confirming first self-sustaining nuclear chain reaction, December 2, 1942.

Illustration depicting the scene on Dec. 2, 1942 (Photo copyright of Chicago Historical Society)

source

Indeed, exactly 15 years later, on this date in 1957, the world’s first full-scale atomic electric power plant devoted exclusively to peacetime uses, the Shippingport Atomic Power Station, reached criticality; the first power was produced 16 days later, after engineers integrated the generator into the distribution grid of Duquesne Light Company.

 source

 

Written by LW

December 2, 2018 at 1:01 am

Really small; really, REALLY fast…

Putting an iodine molecule to work

A team of Japanese researchers set out to test an approach to quantum computing, using a single iodine molecule– and discovered that a single molecule can perform a complex calculation thousands of times faster than a conventional computer.

As PopSci reports, the team used a discrete Fourier transform — a common calculation for performing signal analysis, among other things– for their proof-of principle demo…

Using quantum interference – the vibrations of the atoms themselves – the team was able to run the complete discrete Fourier transform extremely quickly by encoding the inputs into an optically tailored vibrational wave packet which is then run through an excited iodine molecule whose atomic elements are oscillating at known intervals and picked up by a receiver on the other side. The entire process takes just a few tens of femtoseconds (that’s a quadrillionth of a second).

To be clear: this isn’t just lots and lots faster than the fastest conventional computers, these are speeds that are physically impossible on any kind of conventional electronic device.

It’s not yet obvious just how this kind of capability can be engineered to address tasks in the way our current computers do– but this astonishing speed is bound to have equally astonishing impact when it is available.

More at PopSci and at Science Daily.

As we try to imagine the difference that broadband has made, magnified thousands of times over, we might recall that it was on this date in 1958 that the trademark for Velcro was registered.  Inspired by burdock burrs that stuck to his clothes and his dog’s fur after hikes, George de Mestral created the hook-and-loop closure system; he named it as a portmanteau of two French words “velours” (“velvet”)  and “crochet” (“hook”).

source

Written by LW

May 13, 2010 at 12:01 am

%d bloggers like this: