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"In a recent paper published in Physical Review Letters (PRL) Jérôme Duplat and Emmanuel Villermaux developed a method to generate centimeter-sized vacuum bubbles in water with miniature laser-driven explosions, and observed the flash of light produced as the bubble collapsed a not-fully-understood phenomenon known as sonoluminescence." Amazingly they concluded that the temperatrue inside the bubble as it collapses is about 26000 K. At this temperatures some (not me) argue for nuclear fusion... Intriguing stuff!!! Check the videos! Yet another test for the 'Experimental Physics Stagiare' :-)?

For sure no fusion, that starts appr. from about 20keV, not 20kK. Between both there is still a factor of 11500. What I would rather expect is that the conditions are not appropriate to work with Maxwellian distribution functions. If certain fusion products should be measurable, than this would rather confirm (but not proof) the hypothesis that they do not have Maxwellians but something close to monoenergetic. But most probably they will not measure fusion products, hence no fusion, hence no confusion.

Whether it is the frothy milk on your cappuccino, the soapy suds in your bath or the large-scale structure of the universe, foams have intrigued physicists for many years. Now, for the first time in a lab, an international group of scientists has made the Weaire-Phelan foam - which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles.

Does this mean that there is foam that is non regular that can have even less energy structure? "which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles."

"A Soviet supercavitation torpedo called Shkval was able to reach a speed of 370km/h or more - much faster than any other conventional torpedoes," he said. However, The SCMP highlighted two problems in supercavitation technology. First, the submerged vessel needed to be launched at high speeds, approaching 100km/h, to generate and maintain the air bubble. Secondly, it is difficult if not impossible to steer the vessel using conventional mechanisms, which are inside the bubble, without direct contact with water. As a result, its application has been limited to unmanned vessels, fired in a straight line.

can't you just selectively inject the gas so that you control in which direction the bubble forms?

I am also looking into this idea since some time and it seems NASA is already ahead, awarding two contract to investigate magnetoshell aerocapture. This could be interesting for probes that want to enter eg Marsian atmospheres at relatively high velocity. Or for multiple re-entry s/c at Earth. The idea of the experiment, The satellite will carry a copper coil, powered by a lithium-ion battery, that generates a magnetic field around the probe. As it descends, the spacecraft will eject a small amount of plasma. This gets trapped in the magnetic field, creating a protective bubble that stops air molecules colliding with the craft and producing heat.

A few years back Mimmo has worked on this, rather from the theory side if I remember well ...

The power requirements for such a thing must be HUGE!

He also has a recent book: http://www.amazon.com/Filter-Bubble-What-Internet-Hiding/dp/1594203008/

A vast bubble of hot, rarefied gas has been revealed as a source of cosmic rays - the mysterious particles that batter the Earth continuously. The observation of the so-called superbubble, measuring more than 100 light-years across, was made using gamma rays collected by NASA's Fermi satellite and sheds light on the origin of cosmic rays in regions of massive-star formation.

News about the warp drive based on the original Alcubierre metric but with modified shape function. Focus of the reserach was on the interaction between warp bubble and cosmic particles. Result: People on board need shielding. People at the journey's destination might get roasted (by Gamma rays if you want to know).

Sante, Andreas, Luzi, Pacome ... we need you: "But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. He found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977.

Furthermore, if the intensity of the space warps can be oscillated over time, the energy required is reduced even more, White found.

"The findings I presented today change it from impractical to plausible and worth further investigation," White told SPACE.com. "The additional energy reduction realized by oscillating the bubble intensity is an interesting conjecture that we will enjoy looking at in the lab.""

To me, this looks a little bit like the claim "infinity minus one is a little bit less than infinity"...

Luzi I miss you ...

Mindblowing ahah

wow, a big step in genomics...!

But isn't it just yet another word abuse? From what I understand, they just synthesised a genome identical to the one of an existing bacteria... while undoubtedly nice work, this is *very* far from "creating life from scratch"... The fact that you are able to copy something, doesn't mean you understand how it works...

well of course we are far from engineering specific functions, and this is just a copy of a function that already existed. However it is quite impressive and the first time it is done. And the challenge here is not really to "copy" the ADN, but the fact that it works... in other words it is not because you copy the ADN identically that the phenotype (traduction of the ADN) will be the same, which is the case in this experiment.

CMS !

Another bubble is coming to its end, it seems!

And maybe a good thing about antropocene?