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Progress in atomic, optical and quantum science1, 2 has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard3, 4, 5. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks6, 7, their accuracy has remained 16 times worse8, 9, 10. Here we demonstrate a many-atom system that achieves an accuracy of 6.4 × 10−18, which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard-stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units11, the search for time variation of fundamental constants12, clock-based geodesy13 and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering14 (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

They were able to compare the ticking rates of two optical clocks separated by 2000 km, with the objective of computing sea level based on the effect gravity has on the clock ticking rate. They did the experiment using glass optical fibers, but I wonder if we could one day do the same from orbit, to measure the gravitational field around Earth.

isn't this is effectively what pacome has been doing with his time for the last few years? e.g. http://arxiv.org/pdf/1308.6766v1.pdf also mentioning the ACES experiment

The accuracy of these new clocks is insane. Hope there will be soon some of these in space :)

Soon caesium in your watch !

very nice indeed ... how much more accurate are our galileo clocks?

This small clock is around 10^-12 @1d in stability (loose 1 second after 300000 years) and 50 ns in accuracy. For comparison Galileo and GPS clocks are around 10^-14 @1d in stability and 1 ns in accuracy. And ACES/PHARAO will be around 3*10^-16 @1d in stability and 0.3 ps accuracy.

an alarm clock for Marco!

"Our system of five clocks connects with an unprecedented consistency the optical and the microwave worlds." Interesting?

cool! i will be working on the link and the data!

so it took us 70% of the time Earth is in the habitable zone to develop, would this be normal or could it be much faster? In other words, would all forms of life that started on a planet that originated at a 'similar' point in time like us, be equally far developed?

That is actually quite tricky to estimate rly. If for no other reason than the fact that all of the mass extinctions we had over the Earth's history basically reset the evolutionary clock. Assuming 2 Earths identical in every way but one did not have the dinosaur wipe-out impact, that would've given non-impact Earth 60million years to evolve a potential dinosaur intelligent super race.

The opposite might be true - or might not be ;-). Since usually the rate of evolution increases after major extinction events the chance is higher to produce 'intelligent' organisms if these events happen quite frequently. Usually the time of rapid evolution is only a few million years - so Earth is going quite slow. Certainly extinction events don't reset the evolutionary clock - if they would never have happened Earth gene pool would probably be quite primitive. By the way: dinosaurs were a quite diverse group and large dinosaurs might well have had cognitive abilities that come close to whales or primates - the difference to us might be that we have hands to manipulate our environment and vocal cords to communicate in very diverse ways. Modern dinosaur (descendents), i.e. birds, contain some very intelligent species - especially with respect to their body size and weight.

BECs and Clocks, 6th and 7th place, metamaterials 4th place :)

nice list! thanks Pacome!

To survive the winter in the north.

nice ...Sante?

Asimov's Foundation meets ACT's Tipping Point Prediction?

still, some interesting thoughts in there ... "Then you have the 50-year cycles of violence. Turchin describes these as the building up and then the release of pressure. Each time, social inequality creeps up over the decades, then reaches a breaking point. Reforms are made, but over time, those reforms are reversed, leading back to a state of increasing social inequality. The graph above shows how regular these spikes are - though there's one missing in the early 19th century, which Turchin attributes to the relative prosperity that characterized the time. He also notes that the severity of the spikes can vary depending on how governments respond to the problem. Turchin says that the United States was in a pre-revolutionary state in the 1910s, but there was a steep drop-off in violence after the 1920s because of the progressive era. The governing class made decisions to reign in corporations and allowed workers to air grievances. These policies reduced the pressure, he says, and prevented revolution. The United Kingdom was also able to avoid revolution through reforms in the 19th century, according to Turchin. But the most common way for these things to resolve themselves is through violence. Turchin takes pains to emphasize that the cycles are not the result of iron-clad rules of history, but of feedback loops - just like in ecology. "In a predator-prey cycle, such as mice and weasels or hares and lynx, the reason why populations go through periodic booms and busts has nothing to do with any external clocks," he writes. "As mice become abundant, weasels breed like crazy and multiply. Then they eat down most of the mice and starve to death themselves, at which point the few surviving mice begin breeding like crazy and the cycle repeats." There are competing theories as well. A group of researchers at the New England Complex Systems Institute - who practice a discipline called econophysics - have built their own model of political violence and

It's not the scientific activity described in the article that is uninteresting, on the contrary! But the way it is described is just a bad joke. Once again the results itself are seemingly not sexy enough and thus something is sold as the big revolution, though it's just the application of the oldest scientific principles in a slightly different way than used before.

For the first time scientists have identified monthly hormonal cycles in human males

After graphene and blue brain, the European Commission has quietly announced plans to launch a €1-billion Euro project to boost a raft of quantum technologies - from secure communication networks to ultra-precise gravity sensors and clocks.

:-)

Well, it's not yet confirmed... That error would be worse than the magnetic moment of the muon about 10 years ago. There, it was "at least" a conflict of conventions used in the computer codes!

In a statement based on an earlier press release from the OPERA collaboration, CERN said two possible "effects" may have influenced the anomalous measurements. One of them, due to a possible faulty connection between the fiber-optic cable bringing the GPS signals to OPERA and the detector's master clock, would have caused the experiment to underestimate the neutrinos' flight time, as described in the original story. The other effect concerns an oscillator, part of OPERA's particle detector that gives its readings time stamps synchronized to GPS signals. Researchers think correcting for an error in this device would actually increase the anomaly in neutrino velocity, making the particles even speedier than the earlier measurements seemed to show. CERN's statement says OPERA scientists are studying the "potential extent of these two effects" but doesn't indicate which source of error (if either) is likely to outweigh the other. However, Lucia Votano, director of the Gran Sasso laboratory, says the "main suspicion" focuses on the optical-fiber connection. She adds that OPERA researchers deserve credit for "having tenaciously followed this particular evidence via checks completed in the last few days." The two effects will get a new round of tests in May, when the two labs are scheduled to make velocity measurements with short-pulsed beams designed to give readings much more precise than scientists have achieved so far.

good news for LISA...!