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Posts Tagged ‘quantum computing

“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)


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.



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”).


Written by LW

May 13, 2010 at 12:01 am

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