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Hey Guys, Is one of you has any idea about how it's coded? I mean, is it just a basic database of already-written answers or something more sophisticated? Anyway, have fun! Alex

Hi, thanks for your answer. I had a look to the different versions, that's pretty interesting to see how they have evolved over the years.

I was not at all impressed - stopped after a few questions since getting ridiculous answers or trials to change topic

Physicists have simulated two universes colliding inside a metamaterial--  Now, this is cool (if it is true...)

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

Luzi I miss you ...

wow impressive. Could be super useful for astronauts !

from the abstract: "Using a novel imaging and analysis technique on experimental data we estimated pheromone concentrations at all spatial positions in the experimental arena and at different times. Then we derived the response function of individual ants to pheromone concentrations by looking at correlations between concentrations and changes in speed or direction of the ants." [...] "agent based simulations based on the Weber's Law response function determined experimentally produced results compatible with those reported in the literature and reproduced the formation of trails."

Nice article!

Just in time for the end of the winter ....

Physicists in the US have made the first ultrathin flat lens. Thanks to its flatness, the device eliminates optical aberrations that occur in conventional lenses with spherical surfaces. As a result, the focusing power of the lens also approaches the ultimate physical limit set by the laws of diffraction.

Really nice indeed! The new flat ultrathin lens is different in that it is a nanostructured "metasurface" made of optically thin beam-shaping elements called optical antennas, which are separated by distances shorter than the wavelength of the light they are designed to focus. These antennas are wavelength-scale metallic elements that introduce a slight phase delay in a light ray that scatters off them. The metasurface can be tuned for specific wavelengths of light by simply changing the size, angle and spacing between the nanoantennas. "The antenna is nothing more than a resonator that stores light and then releases it after a short time delay," Capasso says. "This delay changes the direction of the light in the same way that a thick glass lens would." The lens surface is patterned with antennas of different shapes and sizes that are oriented in different directions. This causes the phase delays to be radially distributed around the lens so that light rays are increasingly refracted further away from the centre, something that has the effect of focusing the incident light to a precise point.

Multiplexed optical recording provides an unparalleled approach to increasing the information density beyond 1012 bits per cm3 (1 Tbit cm-3) by storing multiple, individually addressable patterns within the same recording volume. Although wavelength, polarization and spatial dimension have all been exploited for multiplexing, these approaches have never been integrated into a single technique that could ultimately increase the information capacity by orders of magnitude.

"As we start to sweep the potential, we didn't initially observe anything," said lead author Robert Sacci, a postdoctoral research fellow with ORNL's FIRST Energy Frontier Research Center. "Then we started seeing shadows-presumably polymeric SEI-forming into a dendritic pattern. It looks like a snowflake forming from the electrode." nice fractals.. as always

By just getting a DNA footprint of a person scientists (and soon police) can produce an image of the person's face. Check out the pictures!

should try it the other way around, deduce the DNA from facial features. That would be even cooler.

Well actually, they did something like that as they searched for common DNA patterns in people that had similar facial features. With a large enough dataset that could provide already 24 DNA tracers that could used reliably for prediction. Imagine if you had even more data available, who needs a model then... just let the NN do it :)

Patterning the glass can make it up to 200 times more resistant to forming cracks

Randall Munroe is simply the best.

Yeah I remember this comic was tough to hack... With Click and Drag it was peanuts to download all the tiles once you figured out the file name pattern, but with this one some strange server-side event thing was used to feed the images at random time intervals... Nice to be able to see it all finally!

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.

Sottos, White, Moore, and their team created 3D vascular networks-patterns of microchannels filled with healing chemistries-that thread through a fiber-reinforced composite. When damage occurs, the networks within the material break apart and allow the healing chemistries to mix and polymerize, autonomously healing the material, over multiple cycles.

Thousands of cycling accidents were re-enacted using stunt riders and crash-test dummies to collect the specific movement patterns of cyclists in accidents. In parallel, normal cycling data has been collected using test cyclists wearing Hövding in everyday cycling. Based on this collected data, they have developed an algorithm that can distinguish normal cycling from accidents. As you don't want the 399GBP device to inflate when taking a sharp corner...

Parallel processing in computing --- Brainet The team sent electrical pulses to all four rats and rewarded them when they synchronised their brain activity. After 10 training sessions, the rats were able to do this 61 per cent of the time. This synchronous brain activity can be put to work as a computer to perform tasks like information storage and pattern recognition, says Nicolelis. "We send a message to the brains, the brains incorporate that message, and we can retrieve the message later," he says. Dividing the computing of a task between multiple brains is similar to sharing computations between multiple processors in modern computers, "If you could collaboratively solve common problems [using a brainet], it would be a way to leverage the skills of different individuals for a common goal."

In this article the authors describe an improvement of their optical microscope techniques for which some of the received a Nobel prize in the past. They achieve resolutions far beyond the optical diffraction limit which is supposed to limit detail resolution due to quantum-mechanical effects. Their techniques include structured illuminiation (producing interference patterns), switchable fluorescent markers as well as multi-frame super resolution enhancement. Authors are able to take a single image in about 0.3 seconds which allows the study of protein processes in the cell: http://spon.de/vgTb7 . Although it is hard to imagine the application of many of these techniques for telescopes (except for super resolution), I am wondering if any of this could help building telescopes with increased optical power or reduced weight. Any ideas..?

As mentioned today during coffee .... we could think to link this to source localization

Really, you think they'd target such a low impact factor publication? ;-P

you will all soon be begging to publish in Acta Futura! We will be bigger than Nature.