20101217

ScienceTop Breakthrough of the Year Science, UCSB Science Magazine has compiled the top breakthroughs of the year, awarding the most significant scientific advance of 2010 to Andrew Cleland and John Martinis (UCSB). "This year’s Breakthrough of the Year represents the first time that scientists have demonstrated quantum effects in the motion of a human-made object," said Adrian Cho, a news writer for Science. "On a conceptual level it extends quantum mechanics into a whole new realm. On a practical level, it opens up a variety of possibilities ranging from new experiments that meld quantum control over light, electrical currents and motion to—perhaps someday—tests of the bounds of quantum mechanics and our sense of reality. This last grand goal might be achieved by trying to put a macroscopic object in a state in which it’s literally in two slightly different places at the same time."

20101122

TEDxCaltech | Feynman's Vision: The Next 50 Years Caltech In recognition of the 50 year anniversaries of Richard Feynman's visionary talk "There's Plenty of Room at the Bottom" and the inauguration of his revolutionary "Feynman Lectures on Physics," the Institute will host TEDxCaltech on January 14, 2011. TEDxCaltech will be a dynamic celebration of Feynman's spirit, curiosity, and scientific vision, and will take ideas worth sharing from Caltech out into the world by celebrating Nobel Laureate, visionary, and “curious character” Richard Feynman, with the theme “Feynman’s Vision: The Next 50 Years.” Speakers include Scott Aaronson, Immanuel Bloch, Sean Carroll, John Preskill, Lenny SusskindDavid Awschalom, Kip Thorne, Charlie Marcus, Don Eigler, Michael Roukes, Craig Venter, and many more.
Future holds key to quantum physics—Obama awards National Medal of Science to Aharonov National Medal of Science  | As reported in USAToday, Yakir Aharanov of Chapman University was in Washington D.C. to collect a National Medal of Science this past week:

"The future is affecting the past—all the time, on the quantum level—allowing physicists to effectively select the future they want their particles to have, within limits, and amplifying the results for a desired outcome."

"I really believe we are close to a second revolution in physics as big as the one a century ago," Yakir Aharonov says. "I feel we are only beginning to free existing quantum theory and to do so, we must think of time in another way."

20101112



Quantum computers may be much easier to build than previously thought Physical Review Letters physorg, arXiv "Quantum computers should be much easier to build than previously thought, because they can still work with a large number of faulty or even missing components, according to a study published today in Physical Review Letters. This surprising discovery brings scientists one step closer to designing and building real-life quantum computing system—devices that could have enormous potential across a wide range of fields, from drug design, electronics, and even code-breaking."

Moving Towards Quantum Computing New York Times "Three major technologies have the potential to move from demonstration computers to practical, highly powerful machines. 'We’re at the stage of trying to develop these qubits in a way that would be like the integrated circuit that would allow you to make many of them at once,' said Rob Schoelkopf, a physicist who is leader of the Yale group. In the next few years you’ll see operations on more qubits, but only a handful. The good news is that while the number of qubits is increasing only slowly, the precision with which the researchers are able to control quantum interactions has increased a thousandfold."

Seth LloydQuantum effects in Biological Systems MIT cbc.ca "Lloyd's biological research, funded by the US Defense Advanced Research Projects Agency, looks at how living things use quantum computation [...] Bird navigation, plant photosynthesis and the sense of smell all represent ways living things appear to exploit the oddities of quantum physics."

20101021

Google Workshop on Quantum Biology "Surprisingly robust quantum effects have been observed in warm biological systems. At the same time, quantum information technology has moved closer to physical realization. This Workshop on Quantum Biology will examine the significance of mesoscopic quantum coherence, tunneling and entanglement in biomolecular membranes, proteins, DNA and cytoskeleton, with particular attention to recently discovered megahertz ballistic conductance in microtubules. Potential utilization of biomolecular quantum information in regulation of cellular activities will be addressed, along with implications for disease and therapy as well as the future development of quantum computation and artificial intelligence.List of Speakers includes Alán Aspuru-Guzik (Harvard), Anirban Bandyopadhyay (Tsukuba), Stuart Hameroff (Tucson), Masoud Mohseni (MIT), Hartmut Neven (Google), Jiří Pokorný (Czech Republic), Elisabeth Rieper (Singapore), Mohan Sarova (Berkeley), Jack Tuszynski (Alberta), and Luca Turin (MIT)
– Quantum Biology · Agenda · Abstracts · Biographies

20100913

"We believe it is timely to set out on a distinct quantum biology agenda. The burgeoning fields of nanotechnology, biotechnology, quantum technology, and quantum information processing are now strongly converging. As quantum engineering and nanotechnology meet, increasing use will be made of biological structures, or hybrids of biological and fabricated systems, for producing novel devices for information storage and processing, to create [novel sensors], and for other tasks. If experiments can shed further light on our understanding of decoherence in biomolecules, at scales where equilibrium thermodynamics no longer applies, this may provide the required foundation for greatly accelerating our progress in manmade quantum computers." 
– Anita Goel, Gerard Milburn, Sandu Popescu, Jeff Tollaksen 
         (
Quantum Aspects of Life)

20100901


Are we living in a designer universe
 
MIT, Sussex "Creating a new universe would require a machine only slightly more powerful than the LHC—and there is every chance that our own universe may have been manufactured in this way.
  – John Gribbin, Telegraph
"A basement universe possesses a fate independent of its parent: harnessing the zero-point energy to trigger inflation becomes a form of applied cosmological engineering. And if basement universes are a naturally occurring phenomenon, as suggested by inflationary cosmological models, the multiverse then takes on the characteristics of an evolutionary algorithm. Though the parent universe in any branching scenario need not have been of intelligent design, once a suitable set of cosmological constants is found through natural inflation, intelligent life could branch out from this point of origin, forming an expanding wavefront of intelligence and altering the evolution of the multiverse itself [...] 
Given that the conditions of the Drake equation are met, a potential explanation for the silence in our immediate neighborhood of the cosmos is that inter-universe panspermia supercedes local expansion. Vernor Vinge’s Singularity may not be only technological; it may be physical. The most powerful computer we can imagine would for all intensive purposes resemble a black hole."
   – C. Altman, Expansion Scenarios 

20100827

Is reality even stranger than quantum mechanics tells us? 
"We know that quantum correlations can be stronger than classical—but why aren't quantum correlations even stronger? Either we are missing something very significant to define quantum theory, or these other theories are all around us too."
 – Caslav Brukner (New Scientist)

20100812

Any quantum state can be cloned in the presence of closed timelike curves  "The possible existence of closed timelike curves (CTCs) draws attention to fundamental questions about what is physically possible and what is not. An example is the "no cloning theorem" in quantum mechanics — which states that no physical means exists by which an unknown arbitrary quantum state can be reproduced, or copied perfectly. We show here that this theorem can be circumvented in the presence of closed timelike curves, allowing for the cloning of an unknown arbitrary quantum state. Since the "no cloning theorem" has played a central role in the development of quantum information science, it is clear that the existence of CTCs would radically change the rules for quantum information technology.
– Tim Ralph, David Ahn, R. B. Mann (arXiv:1008.0221)

20100806

Molecular Simulation with Superconducting Qubits 
"Because Nature isn't classical, damnit, and if you want to make a simulation of nature, you'd better make it quantum mechanical. " —Richard Feynman 
Georgia, UCSB In arXiv:1008.0701, Pritchett, Martinis et al. introduce a protocol for efficient simulation of molecular dynamics using superconducting qubits. "Recent experimental progress suggests that quantum simulation will be one of the first practical applications of quantum computation. We have shown how quantum computers of only a few qubits can simulate arbitrary quantum systems accurately and quickly, even before they reach the regime of fault tolerant quantum computation."

20100717

Decoherence sources in coupled flux qubits NEC, RIKEN In Phys Rev B and concurrent arXiv preprints, Yoshihara, Nakamura and Tsai study decoherence in coupled superconducting flux qubits. "The microscopic origin of decoherence has been elusive so far. It is crucial to identify and eliminate the source of noise sources in order to improve the performance of these devices—the sensitivity of SQUIDs and coherence of qubits. We have quantified the correlations among flux noise and found that the dominant contribution is by local fluctuations."

20100618

Superconducting qubits as artificial atoms
"The demonstrated resonance wave scattering indicates that superconducting quantum devices can be used as building blocks for controllable, quantum coherent, macroscopic artificial structures — in which a plethora of effects can be realized from quantum optics of atomic systems."
NEC 東京大学 This week's Qulink seminar by Yasunobu Nakamura (NEC) reports on recent developments in exploring the quantum optical properties of a superconducting flux qubit coupled to a 1d microwave transmission line. See also: Electromagnetically induced transparency on a single artificial atom (arXiv); Resonance fluorescence of a single artificial atom (Science); Ultimate on-chip quantum amplifier (Phys Rev Lett).

20100611

Quantum Zeno effect with a superconducting qubit NTT In arXiv 1006.2133, Matsuzaki and Semba provide detailed analysis of the Quantum Zeno effect in superconducting qubits: "Superconducting qubits are a promising system to observe the Quantum Zeno effect. We have studied how a sequence of projective measurements can alter the dephasing process, and suggest experimental requirements to observe the Quantum Zeno effect in existing superconducting qubits. It would be possible to demonstrate our prediction utilizing current technologies."

20100318

First quantum effects seen in visible object UCSB The first ever quantum superposition in an object visible to the naked eye has been observed (New Scientist) "The key was to connect the resonating strip to a superconducting qubit—the qubit acts as a bridge between the microscopic and the macroscopic worlds."

Quantum mechanics harnessed to control macroscopic mechanical system (Wired Science) "The goal of the experiment was to see if we could observe quantum mechanical effects in a large, mechanical object. It’s an exciting piece of work. People are interested in pushing the boundaries of quantum mechanics." The techniques harnessed to measure the effect are based upon research earlier reported in "Quantum Entanglement Visible to the Naked Eye" (Nature, Wired Science, BBC)

Room-temperature quantum coherence in photosynthesis (Wired News)"The Nature findings, made at room temperature in common marine algae, show that macroscopic biological coherence operates under everyday conditions. Moreover, similar results from an experiment on another, simpler light-harvesting structure, announced by Engel’s group last Thursday on the pre-publication online arXiv, suggest that photosynthetic coherence is routine. 'There’s every reason to believe this is a general phenomenon,' said Engel. Scholes’ finding is 'an extraordinary result that shows us a new way to use quantum effects at high temperatures.'"

Nature's hot green quantum computers revealed (New Scientist) "Exactly how these molecules remain coherent for so long, at such high temperatures and with relatively large gaps between them, is a mystery,' says Alexandra Olaya-Castro of University College London, who has been collaborating with Scholes to understand the underlying mechanisms and apply them elsewhere. She believes that the antenna's protein structure plays a crucial role. 'Coherence would not survive without it,' she says. 'The hope is that quantum coherence could be used to make solar cells more efficient. The work is going to change the way we think about photosynthesis and quantum computing, Engel says. 'It's an enormous result.'"

Long-lived quantum coherence in photosynthetic complexes at physiological temperature (arXiv) "We present the first evidence that quantum coherence survives at physiological temperature for at least 300 fs—long enough to perform a rudimentary quantum computational operation. This data proves that the wavelike energy transfer process discovered at 77K is directly relevant to biological function. Microscopically, we attribute this long coherence lifetime to correlated motions within the protein matrix encapsulating the chromophores, and we find that the degree of protection afforded by the protein appears constant between 77K and 277K. The protein shapes the energy landscape and mediates an efficient energy transfer despite thermal fluctuations. The persistence of quantum coherence in a dynamic, disordered system under these conditions suggests a new biomimetic strategy for designing dedicated quantum computational devices that can operate at high temperature."

20100223


Josephson junction neurons via physicsandcake Suzanne Gildert offers insights on a recent Phys. Rev. E preprint that proposes to model biologically realistic neurons using Josephson junction arrays. "These 'Josephson junction neurons' reproduce many characteristic behaviors of biological neurons such as action potentials, refractory periods, and firing thresholds, [and] would be orders of magnitude faster than both traditional computer simulations and biological neural networks." See also Quantum neural networks, backpropagation training, adaptive quantum networks.

Quantum Information ScienceDARPA's New Frontier Collins offers this executive-level report on quantum information research at DARPA. "It's been almost a half-century since Intel founder Gordon Moore first observed that ever-shrinking circuitry on silicon chips leads to the doubling of the performance of these chips every 18 months or so. This has been instrumental in bringing rapid progress to the field of information processing. The era of Moore’s Law has been an interesting one, to say the least, but it is nearing its end: Within less than two decades, circuits will have shrunk to the atomic level."