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Unlike any other living thing on Earth, electric bacteria use energy in its purest form - naked electricity in the shape of electrons harvested from rocks and metals. We already knew about two types, Shewanella and Geobacter. Now, biologists are showing that they can entice many more out of rocks and marine mud by tempting them with a bit of electrical juice. Experiments growing bacteria on battery electrodes demonstrate that these novel, mind-boggling forms of life are essentially eating and excreting electricity.

Interesting article about theoretical physics theories vs. experimental verification. Can we state that a theory can be so good that its existence supplants the need for data and testing ? If a theory is proved to be untestable experimentally, can we still say that it is a scientific theory ? (not in my opinion)

There is an interesting approach by Feynman that it does not make sense to describe something of which we cannot measure the consequences. So a theory that is so removed from experiment that it cannot be backed by it is pointless and of no consequence. It is a bit as with the statement "if a tree falls in the forrest and nobody is there to hear it, does it make a sound?". We would typically extrapolate to say that it does make a sound. But actually nobody knows - you would have to take some kind of measurement. But even more fundamentally it does not make any difference! For all intents and purposes there is no point in forcing a prediction that you cannot measure and that therefore has noto reflect an event in your world.

"Mathematics is the model of the universe, not the other way round" - M. R.

In a work published on Nature (http://www.nature.com/nature/journal/v517/n7536/full/nature14090.html#affil-auth) a new DFT based simulation of convection in Earth's Core iron shows that electron-electron scattering has a similar contribution to electron's thermal vibration. The outcome is that using the old dynamo theory the simulation matches the Earth magnetic field experimental results, solving an 80 years old puzzle.

Yay to science! I'm always intrigued by related experiments that try to measure material properties at the GPa range. Especially, the efforts of reaching 'metallic hydrogen' (http://en.wikipedia.org/wiki/Metallic_hydrogen), requiring pressures above 25GPa at which hydrogen becomes conductive. It is thought that gas giant planets could have such a core, but no-one has been able to produce/verify this theory as off yet.

An exhaustive overview of all possible advanced rocket concepts, eg.. "As an example, consider a photon rocket with its launching mass, say, 1000 ton moving with a constant acceleration a =0.1 g=0.98 m/s2. The flux of photons with E γ=0.5 MeV needed to produce this acceleration is ~1027/s, which corresponds to the efflux power of 1014 W and the rate of annihilation events N'a~5×1026 s−1 [47]. This annihilation rate in ambiplasma l -l ann corresponds to the value of current ~108 A and linear density N ~2×1018 m−1 thus any hope for non-relativistic relative velocity of electrons and positrons in ambiplasma is groundless." And also, even if it would work, then one of the major issues is going to be heat dispersal: "For example, if the temperature of radiator is chosen T=1500 K, the emitting area should be not less than 1000 m2 for Pb=1 GW, not less than 1 km2 for Pb=1 TW, and ~100 km2 for Pb=100 TW, assuming ε=0.5 and δ=0.2. Lower temperature would require even larger radiator area to maintain the outer temperature of the engine section stable for a given thermal power of the reactor."

The problem is not achieving a high energy density, that we can already do with nuclear fission, the question however is how to confine or harness this power with relatively high efficiency, low waste heat and at not too crazy specific mass. I see magnetic confinement as a possibility, yet still decades away and also an all-or-nothing method as we cannot easily scale this up from a test experiment to a full-scale system. It might be possible to extract power from such a plasma, but definitely well below breakeven so an additional power supply is needed. The fission fragments circumvent these issues by a more brute force approach, thereby wasting a lot of energy for sure but at the end probably providing more ISP and thrust.

Sure. However, the annihilation based photon rocket concept unifies almost all relevant drawbacks if we speak about solar system scales, making itself obsolete...it is just an academic testcase.

A British company has produced a "strange, alien" material so black that it absorbs all but 0.035 per cent of visual light, setting a new world record. To stare at the "super black" coating made of carbon nanotubes - each 10,000 times thinner than a human hair - is an odd experience.

Finally! Nowadays blacks were always too bright for my taste...

"No matter how fast light travels, it finds the darkness has always got there first, and is waiting for it." I will keep waiting for my darkness-emitting diodes...

Their accuracy is orders of magnitude better than what is currently being used, however at the moment, it sounds like quite a large setup -> they're working on getting it down to 1m^3 :o, still any gravity mapping instruments could benefit from these in the future.

Actually GPS is much more accurate, but as it doesnt work under water, the only alternative (without building an underwater GPS equivalent using probes) is to use cumulative accelerometer data. But as this is prone to drifting over time, quantum systems like this can help improving the accuracy significantly.

Very true :). I was thinking though when you want to remove 'noise' from any gravity mapping experiment, highly accurate accelerometers are required, like those used in GOCE.

Today we released the Astro Drone app. People that have the Parrot AR drone can freely download the game. While they fly their drone in the real world, they are trying to dock to the ISS in the virtual world. But the app is more than a game. Players can choose to participate in a scientific crowd sourcing experiment that aims to improve autonomous capabilities of space probes, such as landing, obstacle avoidance, and docking. If participating, the app extracts visually salient features from the images made by the drone's camera. The features are then combined with the estimates of the drone's state and uploaded. The data is then used in a research aiming to improve robot navigation.

Visit the main ESA website and you'll be greeted with a 6-minute Rosetta promo movie by a kickass Polish artist... P.S. You can also find the video here. P.P.S It seems I've just discovered a way to hijack old diigo entries ;-)

"Collider is an arty audiovisual experience that provides a first-person perspective of a particle hurtling through the Large Hadron Collider"... with the use of the Leapmotion sensor and Oculus Rift hmd. Come to my desk if you wanna try it :) (not that fun actually)

we will come when you figure out how to capture a particle!!! or a dragonball, is the same

So basically we can photograph light now. Not just detect photons but photograph LIGHT WAVES. Really clever setup BTW.

One year after the ACT...

Microsoft project Natick deploys cloud servers inside a vessel under seawater. A cool story about crossing competences of different people around an innovative solution. "In my experience the trick to innovating is not coming up with something brand new, but connecting things we've never connected before, pairing different technology together."

the quote could come from ACT ...

A new experiment proved the existence of a new effect in nanomaterials: flexo-electric effect. The material has built-in mechanical tension that changes shape when you apply electrical voltage, or that generates electricity if you change its shape and was theorized some decades ago. Now, SrTiO3 allowed to observe this new effect, being comparable with piezoelectric effect.

My old twente university group! :)

Isn't muscle wire quite old technology though?

IBM for the first time ever is making quantum computing available to the public, providing access to a quantum processor via the cloud. Users can create algorithms and run experiments and get inspired by the possibilities of a quantum computer.

Looks interesting.. Have you tried it?

Mathias Troyer from ETH Zurtich gave a talk in Leiden where he showed what he wants to be the replacement to this IBM programming or the best ally of it - program quantum computers with, for instance, python code. Nice developments coming from the quantum coding field, besides the fact we are ages away from a practical quantum computer.

Why do we sleep? One answer could be: to clear waste products accumulated during the day. To prevent aging and neurodegeneration, the body must maintain homeostasis. What would happen if we experience chronic sleep loss? What would happen if microgravity impairs the cerebrospinal fluid to flush the brain? What would happen if cosmic radiations increase the amount of daily waste products?

An experiment at the Fermi National Accelerator Laboratory near Chicago has detected far more electron neutrinos than predicted - a possible harbinger of a revolutionary new elementary particle called the sterile neutrino, though many physicists remain skeptical.

"The Neuromorphic Computing Platform allows neuroscientists and engineers to perform experiments with configurable neuromorphic computing systems. The platform provides two complementary, large-scale neuromorphic systems built in custom hardware at locations in Heidelberg, Germany (the "BrainScaleS" system, also known as the "physical model" or PM system) and Manchester, United Kingdom (the "SpiNNaker" system, also known as the "many core" or MC system)."

How do humans construct their mental representations of the passage of time? The universalist account claims that abstract concepts like time are universal across humans. In contrast, the linguistic relativity hypothesis holds that speakers of different languages represent duration differently. The precise impact of language on duration representation is, however, unknown. Here, we show that language can have a powerful role in transforming humans' psychophysical experience of time. Contrary to the universalist account, we found language-specific interference in a duration reproduction task, where stimulus duration conflicted with its physical growth. When reproducing duration, Swedish speakers were misled by stimulus length, and Spanish speakers were misled by stimulus size/quantity. These patterns conform to preferred expressions of duration magnitude in these languages (Swedish: long/short time; Spanish: much/small time). Critically, Spanish-Swedish bilinguals performing the task in both languages showed different interference depending on language context. Such shifting behavior within the same individual reveals hitherto undocumented levels of flexibility in time representation. Finally, contrary to the linguistic relativity hypothesis, language interference was confined to difficult discriminations (i.e., when stimuli varied only subtly in duration and growth), and was eliminated when linguistic cues were removed from the task. These results reveal the malleable nature of human time representation as part of a highly adaptive information processing system.

A tiny self-organized mesh full of artificial synapses recalls its experiences and can solve simple problems. Its inventors hope it points the way to devices that match the brain's energy-efficient computing prowess.