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in title, tags, annotations or urlSeismic Metamaterials Could Cloak Dams and Power Stations - Technology Review - 2 views
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Metamaterials that absorb seismic waves rather than steer them, might be a better way to protect some buildings, say engineers
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what are seismic metamaterials?
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must look funny ... They calculate the properties of such a metatmaterial and how it might be constructed with a basic repeating unit in the form of a concrete cylinder some 18 metres in diameter, with four perpendicular holes in its sides (see picture). These cylinders, perhaps varying in size to absorb a range of seismic wavelengths, would need to surround the foundations of a building in cylindrical shells some 60 metres across. That needn't be prohibitively expensive but it would be a big structure that could only be constructed around isolated buildings (thereby somewhat negating the supposed benefit that other buildings in the earthquake 'shadow' might also be protected).
Artificial Braneworlds Made to Collide In Lab - Technology Review - 4 views
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Physicists have simulated two universes colliding inside a metamaterial-- Now, this is cool (if it is true...)
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Hm, they use more or less everything I don't especially like. They are nonmagnetic, so the relation materialGR is already rather weak. Usually, experimentalists prefer nonmagnetic media, since they are cheaper and broadband. At least the broadband is no argument here, since the frequency defines the "mass", which I find a rather strange point of view. And finally, they use strong anisotropy as a model of "time", which is rather problematic. Of course, the spatial direction with eps<0 appears in the wave equation with the same sign as time. But this does not mean that it behaves like time. But to teach material physicists that time is more than just a different sign in the wave equation seems to be as hopeless as to teach them that a black hole is more than something that absorbs all light... SIGHHH
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Luzi I miss you ...
A Brain Wave Worth a Thousand Words - ScienceNOW - 0 views
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In a new study, neuroscientists connected a network of electrodes to the hearing centers of 15 patients' brains (image above) and recorded the brain activity while they listened to words like "jazz" or "Waldo." They saw that each word generated its own unique pattern in the brain. So they developed two different computer programs that could reconstruct the words a patient heard just by analyzing his or her brain activity.
Gravitational waves: have US scientists heard echoes of the big bang? - 1 views
Dolphin inspired radar #biomimicry - 2 views
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The device, like dolphins, sends out two pulses in quick succession to allow for a targeted search for semiconductor devices, cancelling any background "noise",
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Could it be used to measure ocean acidification? I found a study that links sound wave propagation with ocean acidity. Maybe we are able to do such measurement from space even? "Their paper, "Unanticipated consequences of ocean acidification: A noisier ocean at lower pH," published last week in the journal Geophysical Research Letters, found that fossil fuels are turning up the ocean's volume. Since the beginning of the Industrial Revolution, the overall pH of the world's oceans has dropped by about 0.1 units, with more of the changes concentrated closer to the poles. The authors found that sound absorption has decreased by 15 percent in parts of the North Atlantic and by 10 percent throughout the Atlantic and Pacific"
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The last time I asked an oceanographer for the use of acoustic waves, she said it is still a bit problematic method to take into account its data, but we were referring to measuring ocean circulation. It may be more conclusive for PH measurements, though. The truth is that there is a whole underwater network with pulse emmitters/receivers covering the North Atlantic basin, remnant infrastructure for spying activities in the WW2 and in the cold war, that stays unexploited. We should look more into this idea
Time 'Emerges' from #Quantum Entanglement #arXiv - 1 views
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Time is an emergent phenomenon that is a side effect of quantum entanglement, say physicists. And they have the first exprimental results to prove it
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I guess I tentatively agree with you on both points. In the end there might anyway be surprisingly little overlap between the way that we describe what nature does and HOW it does it... :-D
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Congratulations! 100% agree.
Electromagnetism generated by symmetry breaking in dielectrics - 0 views
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Using dielectric materials as efficient EM radiators and receivers can scale down these antenna's to the chip level, reducing both weight and power consumption. The infamous internet-of-things one step closer. But could we also transmit power this way?? "In dielectric aerials, the medium has high permittivity, meaning that the velocity of the radio wave decreases as it enters the medium," said Dr Dhiraj Sinha, the paper's lead author. "What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years." The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration The researchers found that by subjecting the piezoelectric thin films to an asymmetric excitation, the symmetry of the system is similarly broken, resulting in a corresponding symmetry breaking of the electric field, and the generation of electromagnetic radiation.
Mapping Turbulence in the Solar Wind - 0 views
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a team reports studying the turbulent flow of solar wind particles by monitoring the accompanying waves of magnetic field. The team used a cluster of satellites to measure the field in unprecedented spatial detail. They found that the waves aren't equally strong in all directions but are larger in certain preferred directions, as theorists had predicted. The observation will help astrophysicists better understand the consequences of the solar wind, including its effect on the transmission of cosmic rays, particles that arrive at Earth from elsewhere in our galaxy.
Lockheed Martin buys first D-Wave quantum computing system - 1 views
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D-Wave develops computing systems that leverage the physics of quantum mechanics in order to address problems that are hard for traditional methods to solve in a cost-effective amount of time. Examples of such problems include software verification and validation, financial risk analysis, affinity mapping and sentiment analysis, object recognition in images, medical imaging classification, compressed sensing and bioinformatics.
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According to the company's wikipedia page, the computer costs $ 10 million. Can we then declare Quantum Computing has officially arrived?! quotes from elsewhere in the site: "first commercial quantum computing system on the market"; "our current superconducting 128-qubit processor chip is housed inside a cryogenics system within a 10 square meter shielded room" Link to the company's scientific publications. Interestingly, this company seems to have been running a BOINC project, AQUA@home, to "predict the performance of superconducting adiabatic quantum computers on a variety of hard problems arising in fields ranging from materials science to machine learning. AQUA@home uses Internet-connected computers to help design and analyze quantum computing algorithms, using Quantum Monte Carlo techniques". List of papers coming out of it.
Resource Efficiency: The Sixth Wave of Innovation | Epicenter | Wired.com - 7 views
SpringerLink - Buchkapitel - 1 views
Google Wave Preview - 2 views
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Looks really cool! And it's open source :)
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Don't know if you've noticed, but the current version is becoming more and more usable... did you try it already in your collaborative work?
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We've used it a bit with Juxi and Leopold for the work on the new issue of acta futura, and I think it is quite nice. The problem right now is that only a few people in the team have an account (and I have exhausted my invitations). Maybe you have one or two you are willing to share? :)
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