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"The BICEP2 data would eliminate about 90% of inflationary models, Andrei Linde, a cosmologist at Stanford University in California, told a packed auditorium at MIT the day after the BICEP2 announcement (see picture below). Many of those models do not produce gravitational waves at detectable levels, said Linde, who is one of the founders of inflation theory." Is there any hope for LISA now?

Of course - the data is more proof that GWs exist!!

so you don't expect any impact on the science objectives of Lisa at all?

Theoretized 80 years ago was Breit-Wheeler pair production in which two photons result in an electron-positron pair (via a virtual electron). It is a relatively simple Feynmann diagram, but the problem is/was how to produce in practice a high energy photon-photon collider... The collider experiment that the scientists have proposed involves two key steps. First, the scientists would use an extremely powerful high-intensity laser to speed up electrons to just below the speed of light. They would then fire these electrons into a slab of gold to create a beam of photons a billion times more energetic than visible light. The next stage of the experiment involves a tiny gold can called a hohlraum (German for 'empty room'). Scientists would fire a high-energy laser at the inner surface of this gold can, to create a thermal radiation field, generating light similar to the light emitted by stars. They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons. It would then be possible to detect the formation of the electrons and positrons when they exited the can. Now this is a good experiment... :)

True, but isnt it E2=(pc)^2 + (m0c^2)^2 such that for photons E\propto{pc} and for mass E\propto{mc^2}. I agree it will take a lot of energy, but this assumes that that wont be the problem at least. The question therefore is whether the mass flow of the photon rocket (fuel consumed to create photons, eg fission/fusion) is higher/lower than the mass flow for e-p creation. You are probably right that the low e-p cross-section will favour direct use of photons to create low thrust for long periods of time, but with significant power available the ISP might be higher for e-p pair creation.

In essence the equation tells you that for photons with zero rest mass m0 all the energy will be converted to momentum of the particles. If you want to accelerate e-p then you first spend part of the energy on creating them (~511 keV each) and you can only use the remaining energy to accelerate them. In this case the equation gives you a lower particle momentum which leads to lower thrust (even when assuming 100% acceleration efficiency). ISP is a tricky concept in this case because there are different definitions which clash in the relativistic context (due to the concept of mass flow). R. Tinder gets to a I_SP = c (speed of light) for a photon rocket (using the relativistic mass of the photons) which is the maximum possible relativistic I_SP: http://goo.gl/Zz5gyC .

A personal interest of mine that I want to explore a bit more in the future. I just bought a ZigBee electricity monitor and I am wondering whether from the signal of the mains one could detect (reliably) the oven turning on, lights, etc. Probably requires Neural Network training. The idea would be to make a simple device which basically saves you money by telling you how much electricity you are wasting. Then again, its probably already done by Google...

Randomly I found this: http://spectrum.ieee.org/view-from-the-valley/consumer-electronics/gadgets/curb-startup-home-electricity-tracking Isn't it a similar kind of stuff Thijs?

haha, yep, that's it... but we can do better than that right! :)

NASA validates the EmDrive (http://emdrive.com/) technology for converting electrical energy into thrust. (from the website: "Thrust is produced by the amplification of the radiation pressure of an electromagnetic wave propagated through a resonant waveguide assembly.")

I have to join the skeptics on this one ...

Two apps - the Distributed Electronic Cosmic-ray Observatory (DECO) and Cosmic Rays Found in Smartphones (CRAYFIS) - transform smartphones into miniature cosmic-ray detectors. They use the CMOS chips inside phones' onboard cameras to detect the secondary particles produced when cosmic rays - energetic, charged subatomic particles arriving from beyond the solar system - collide with air molecules in the Earth's atmosphere

Researchers have proposed a new "acoustic topological insulator" that could help alleviate sound scattering problems by transmitting sound in certain directions without any backscattering.

If I understood correctly the triangular structure would channel the incident sound wave to a unique direction between two options, according to the rotation direction of the cylinders included in its mesh. So, one (possibly two) directions left to detect the hypothetical submarines? Very interesting though, I hope no oceanographers take measurements simultaneously to the signals as climate models will get even more wrong...!

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

Good old Darwin...

From the section Science & Environment Scientists are claiming a stunning discovery in their quest to fully understand gravity. They have observed the warping of space-time generated by the collision of two black holes more than a billion light-years from Earth.

Soft Robots Scientists from Cornell University and the Italian Technology Institute in Pontedera have developed an elastic robotic skin that is able to stretch up to five times its size, change colors, and even detect pressure. The luminescent skin, partly funded by the Army and Air Force's research wings, is comprised of different kinds of specialized silicone, making it flexible and soft.

related video here: http://imgur.com/gallery/q57U40Y

Inspired by the work that was done at the ACT, I continued working on optical flow landing at TU Delft. Today Bio & Bio published my article on a new theory that allows drones to see distances with a single camera. It shows that drones approaching an object with an insect-inspired vision strategy become unstable at a specific distance from the object. Turning this weakness into a strength, drones can actually use the timely detection of that instability to estimate distance. The new theory will enable further miniaturization of autonomous drones and provides a new hypothesis on flying insect behavior. Video: https://www.youtube.com/watch?v=Fm7SMJp8EA4&feature=youtu.be Article: http://iopscience.iop.org/article/10.1088/1748-3190/11/1/016004

According to their Nature article, they can detect "a tunnel less than 1m across, buried 2m underground" just from its gravitational difference. Using a device that they predict could cost ~100 € in mass production. UK researchers have built a small device that measures tiny fluctuations in gravity, and could be used to monitor volcanoes or search for oil. Such gravimeters already exist but compared to this postage stamp-sized gadget, they are bulky and pricy.

The paper I talked about with the proof of a gigantic lava tube discovered in 2017 from data of the Japanese lunar mission

Given the size of this thing we may consider a project on city urban planning inside. I would see a rocket-port outside the crater, some lift systems to get in, a closed dome with artificial atmosphere where to develop the city possible trekking routes on the lunar surface, a mirror system to get sunlight in, an energy factory just outside the entry.

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 goal of the APT program is to control and direct plant physiology to detect chemical, biological, radiological, and/or nuclear threats, as well as electromagnetic signals. " Now that is an advanced concept...

and look at this exceptional insight: "plants are easily deployed, self-powering, and ubiquitous in the environment, and the combination of these native abilities with specifically engineered sense-and-report traits will produce sensors occupying new and unique operational spaces" :-)

More info on dark matter ...

beautiful! anybody knows of similar trials to fool EO data classifiers?

I am not aware of any similar trials, yet this study remind me of generative adversarial talking heads https://arxiv.org/pdf/1803.07716.pdf https://www.youtube.com/watch?v=p1b5aiTrGzY