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The quick-and-dirty explanation is that the E8 "object" is a nasty-ass shape that exists in 248 dimensions, and which is notable for various reasons that only mathematicians can really grasp fully, but can be understood by the layman as pertaining to the concept of symmetry. It was discovered in the 1890s, but due to its size was never fully computed until a couple of years ago (the solution is a massive matrix of polynomials taking up 60 GB of storage). Oddly, various aspects of the E8 solution were reminiscent of formulae in the Standard Model, and Lisi has managed to come up with a coherent explanation of why this is. Various aspects of the E8 object's structure appear to explain formerly mysterious facts, such as why elementary particles are grouped into their various families. They also suggest new and undiscovered particles, which may give this theory a very clear set of test cases if it survives that long.

I don't understand a lot of it, but I know that scientists have been trying to prove the theory of everything. I believe it's called M theory. I don't know enough about it to truly appreciate this model, but it is beautiful and elegant... just what you would expect something to look like that would be the theory of everything. Garrett Lisi is a name we should all remember. I think we will be hearing more from him.

Here's a story that's doing the rounds on the blogs - Scientists Invent 30 Year Continuous Power Laptop Battery.



The story is written in peculiarly convoluted prose, but appears to be saying that a breakthrough in nuclear energy technology means that we'll all be running around with magic batteries in mobile and laptop, in "two to three years". They'll be perfectly safe, will save the world, and will probably last longer than you will.



Sadly, no. As with the best techno-rubbish, there is a story in there, but you'll be pootling around the skies in jetpacks before you're powering your Dell from neutron decay.



That story is betavoltaics. This is a way of generating electricity much as solar cells generate power from photons, only by using high energy electrons generated from the beta decay of certain radio-isotopes. If you pick your isotope well -- the examples given use tritium, a radioactive form of hydrogen - the other decay products are inert, and in theory you can generate useful amounts of power for a reasonable length of time. As with every radioactive system, it has a half-life depending on the isotope; tritium's half-life is around twelve years, so every decade or so your battery will halve in power - but that won't change, no matter how little or much power you take out in the duration.



Beats Duracell, right?



Again, sadly, no. There are a few small problems.



One is that the sort of atomic structures that generate power when bombarded with high energy electrons are the sort that tend to fall apart when bombarded with high energy electrons. While solar cells have the same problem, it's to a much lesser extent. There's a lot of research into making materials that don't suffer so much, but it remains a serious issue.



Secondly, while it's true that a tritium-powered battery will eventually turn into an inert, safe lump of nothing much, and while it's also true that a modest amount of shielding will keep the radioactivity within the battery the while, there's the small problem that if you break the battery during its life the nasties come out.



Thirdly, they don't have a great conversion efficiency. Around 25 percent is the best you can get - which is pretty good, but leaves 75 percent sloshing around as heat. That means a 25 watt battery will get plenty warm.



Lastly, they're not very good batteries. Even the latest devices, which are very clever in the way they saturate a porous structure with the gas and thus usefully capture quite a large number of the energetic electrons, have an energy density of the order of twenty five watts per kilo. Lithium ion batteries, the sort you have in your laptop, manage 1.8 kilowatts per kilo. That's 72 times more bang per gram. Do you fancy carrying a battery 72 times heavier than the one you have at the moment, especially if it's hotter than a sixty watt light bulb?



Which is not to say that betavoltaics aren't useful. There are some interesting ideas for using small betavoltaic cells to constantly trickle charge more conventional batteries, which helps circumvent some of the capacity issues.



And there are plenty of places where it's difficult or dangerous to have to change or recharge the power source, and many of those only need small amounts of juice.



Those places do not currently include your lap. You may possibly be relieved to hear this.

hy water would act this way was a surprise, Fuchs told PhysOrg.com. But the group’s analyses have shown that the explanation may lie within the nature of the water’s structure. Initially, the bridge forms due to electrostatic charges on the surface of the water. The electric field then concentrates inside the water, arranging the water molecules to form a highly ordered microstructure. This microstructure remains stable, keeping the bridge intact.



The scientists reached the microstructure hypothesis after observing that the density of the water changes between the beaker edges and the center of the bridge. A microstructure consisting of an arrangement of water molecules could have a similar density variation.



In their experiments, the scientists also discovered the existence of high frequency oscillations inside the bridge, and they observed corresponding inner structures with a high-speed camera and visualization system. Unlike the much slower surfaces waves, these high frequency oscillations weren’t caused by surface tension. Rather, the scientists predict that the oscillating structures were triggered by the waviness of the voltage supply itself.



The researchers noticed a pattern with the inner structures: every experiment started with a single inner structure, which then decayed into additional structures after a few minutes of operation. The group thought that this decay might be caused by either dust contamination or the increasing temperature of the water bridge under the electric field. As the water temperature increased from 20 degrees Celsius to more than 60 degrees Celsius—which took about 45 minutes—the bridge collapsed.



The scientists explain that the unusual effect of the floating water bridge, as well as the microstructures they observed during the interaction of water with electric fields, could be another piece to the puzzle of the structure of water. The group said that they are currently investigating how highly ordered microstructures may explain the density change in the water bridge, with the results to appear in a future publication.