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"When a control laser is fired at the crystal, a complex quantum-level reaction turns it the opaque crystal transparent. A second light source is beamed into the crystal before the control laser is shut off, returning the crystal to its opaque state. This leaves the light trapped inside the crystal, and the opacity of the crystal keeps the light trapped inside from bouncing around, effectively bringing light to a full stop." is the simple explanation, but I am not sure how this is actually possible with the current laws of physics

There are two ways to make slow light: material slow light and structural slow light, where you either change the material or the structural properties of your system. Here they used EIT to make material slow light, by inducing transparency inside an otherwise opaque material. As you change the absorption properties of a material you also change its dispersion properties, the so-called Kramers-Kronig relations. A rapid positive change in the dispersion properties of a material will give rise to slow light. To effectively stop light they switched off the control beam, bringing back the opaque state. Another control beam is then used to retrieve the probe pulse that was 'frozen' inside the medium. Light will be halted according to the population lifetime on the energy level (~ 100s). They used an evolutionary algorithm to find an optimal pulse preparation sequence to reach close to the maximum possible storage duration of 100s. Interesting paper!

So it is not real storage then in a sense, as you are stimulating an excitation population which retains the phase information of your original pulse? Still it is amazing that they could store this up to 100s and retrieve it with a probe pulse, but light has never been halted.

We discussed this today during coffee. The inventor claims that he claims that a pressure differential can push hydrogen through a proton conductive membrane (thereby stripping off the electrons) which flow through an electric circuit and provide electric power. The type of membrane is fairly similar to that found in a hydrogen fuel cell. If the pressure differential is cause by selective heating this is in essence a heat engine that directly produces electricity. The inventor claims that this could be a high efficiency alternative to thermoelectric devices and could even outperform PV and Sterling engines with an efficiency close to that of fuel cells (e.g., ~60% @ dT=600K). I could not find any scientific publications as the inventor is not affiliated to any University - he has however an impressive number of patents from a very wide field (e.g., the "Super Soaker" squirt gun) and has worked on several NASA and US military projects. His current research seams to be funded by the latter as well. Here are some more links that I found: http://www.theatlantic.com/magazine/archive/2010/11/shooting-for-the-sun/308268/ http://www.johnsonems.com/?q=node/13 http://scholar.google.nl/scholar?q=%22lonnie+g+johnson%22+&btnG=&hl=nl&as_sdt=0%2C5

If you pry open one of today's ubiquitous high-tech devices-whether a cellphone, a laptop, or an electric car-you'll find that batteries take up most of the space inside. Indeed, the recent evolution of batteries has made it possible to pack ample power in small places.

solidstate batteries would be perfect indeed, but up to now I know of no solid electrolyte that can do the trick. The article itself does not mention any material beyond superionic lithium-ion conductors, but does not specify which one in particular. The premis seems to be "if it conducts fast enough, the battery can conduct efficiently"

very nice success by what we called in 2003 "the second space age" ... for Joris: (related to the discussion we had the other day) But the spacecraft will be assembled, integrated and tested in the United States and will include U.S. hardware, meaning they would not be allowed for launch aboard Indian or Chinese rockets under current U.S. regulations.

does he also have to pay property tax?

so how does that state get his money from this type of economy? where is the VAT in there?

Last time I checked the "state" was still loosing money. But their main income is the sale of resources. Mostly new land, but I believe at some point they wanted to sell their initial planet too.

Cosmic Vision missions, some of which to be selected before the end of 2011.. Favorite phrase: "Mindful of the recent criticism the agency has received from member states on the issue of cost overruns, Professor David Southwood, Esa's director of science and robotics, told the teams: "Industry and the science community need to get to work on this; it's a collective responsibility."" :-> reference class forecasting!

Eleven of ESA's 18 Member States are participating in the ExoMars Programme: Austria, Belgium, France, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland, and the United Kingdom, plus Canada. Greece doesn't participate. pfffff national debt, crisis and bullshit

This is the community that states mammals have cognitive maps. Good work, especially by the Moser-couple.

The Schrodinger cat with drums, that's for Nik ;)

CHARLI is the first untethered, autonomous, full-sized, walking, humanoid robot with four moving limbs and a head, built in the United States. His two long legs and arms can move and gesture thanks to a combination of pulleys, springs, carbon fiber rods, and actuators. CHARLI soon will be able to talk as well.

"The mind reader is Gerwin Schalk, a 39-year-old biomedical scientist and a leading expert on brain-computer interfaces at the New York State Department of Health's Wads­worth Center at Albany Medical College. The 28Austrian-born Schalk, along with a handful of other researchers, is part of a $6.3 million U.S. Army project to establish the basic science required to build a thought helmet-a device that can detect and transmit the unspoken speech of soldiers, allowing them to communicate with one another silently." ...

This reminds me... http://www.imdb.com/title/tt1234548/

they have found Christina's dog !!

Non-steady state aerodynamics of flapping flight. Rather for aerospace engineers but in my eyes interesting...

Review about the state-of-the-art in biological nanoengines

Spectral dispersion of light on a finite-size surface plasmon polaritonic (SPP) crystal has been studied. The angular wavelength separation of one or more orders of magnitude higher than in other state-of-the-art wavelength-splitting devices available to

could this also be useful - I doubt so since it seems to use air flow for cooling but don#t really understand the mechanisms ...

he JTEC is an all solid-state engine that operates on the Ericsson cycle. Equivalent to Carnot, the Ericsson cycle offers the maximum theoretical efficiency available from an engine operating between two temperatures.

Recently, it was shown that slowly rotating neutron stars exhibit an interesting correlation between their moment of inertia I, their quadrupole moment Q, and their tidal deformation Love number λ (the I-Love-Q relations), independently of the equation of state of the compact object. By exploiting this relation, we can describe quite accurately the geometry around a neutron star with fewer parameters, even if we don't know precisely the equation of state. Side note: I-Love-Q relations? Some inner chuckles in the Fundamental Physicist community.. :)

12 new NIAC 1 studies - many topics familiar to us ... please have a look at those closest to your expertise to see if there is anything new/worth investigating (and in general to be knowledgeable on them since we will get questions sooner or later on them)
Principal Investigator Proposal Title Organization City, State, Zip Code
Atchison, Justin Swarm Flyby Gravimetry Johns Hopkins University Baltimore, MD 21218-2680
Boland, Eugene Mars Ecopoiesis Test Bed Techshot, Inc. Greenville, IN 47124-9515
Cash, Webster The Aragoscope: Ultra-High Resolution Optics at Low Cost University of Colorado Boulder, CO 80309-0389
Chen, Bin 3D Photocatalytic Air Processor for Dramatic Reduction of Life Support Mass & Complexity NASA ARC Moffett Field, CA 94035-0000
Hoyt, Robert WRANGLER: Capture and De-Spin of Asteroids and Space Debris Tethers Unlimited Bothel, WA 98011-8808
Matthies, Larry Titan Aerial Daughtercraft NASA JPL Pasadena, CA 91109-8001
Miller, Timothy Using the Hottest Particles in the Universe to Probe Icy Solar System Worlds John Hopkins University Laurel, MD 20723-6005
Nosanov, Jeffrey PERISCOPE: PERIapsis Subsurface Cave OPtical Explorer NASA JPL Pasadena, CA 91109-8001
Oleson, Steven Titan Submarine: Exploring the Depths of Kraken NASA GRC Cleveland, OH 44135-3127
Ono, Masahiro Comet Hitchhiker: Harvesting Kinetic Energy from Small Bodies to Enable Fast and Low-Cost Deep Space Exploration NASA JPL Pasadena, CA 91109-8001
Streetman, Brett Exploration Architecture with Quantum Inertial Gravimetry and In Situ ChipSat Sensors Draper Laboratory Cambridge, MA 02139-3539
Wiegmann, Bruce Heliopause Electrostatic Rapid Transit System (HERTS) NASA MSFC Huntsville, AL 35812-0000

Eh, the swarm flyby gravimetry is very similar to the "measuring gravitational fields" project I proposed in the brewery