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this is the infrastructure that satellites have to compete with ....

I guess you are right... Is ACT already planning a find-and-cut expedition?

now that we have the boat and thanks to Camilla it is still floating after the deluge ....

Sounds quite ACT-ish...

Some quite obvious, some perhaps a bit less...

Good to solve the Landing problem!!!! No skew due to perspective and gimballed by definition

Very very nice idea! Unfortunately samples show they still have quite some work to do on the image processing side... which is interesting because there are very good open-source solutions for stitching.

Article mainly on anti-satellite testing by the Chinese and on US and Russian tests (2nd page) - quite extensive and technical but interesting

It turns out that falling along any straight line through the Earth takes 42 minutes (Gravity train). I think this has not been opted as an explanation of Douglas Adams' 42 but this fact is definitely quite beautiful.

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 .

This could become quite relevant in future control systems if the setup can be made simple to keep alive and stable. I was doing some follow-up on a story about people controlling aircraft with their brainwaves (through EEG) when I ran into this really cool story. The idea of growing the neurons in patterns is incidentally very similar to the Physarium slime-mold stuff that Dario and me were curious about a little while ago.

I think we already had a discussion on this during a wednesday meeting :P

Oh, I thought that was on the little robot that was controlled by rat neurons and bumped into EVERYTHING. The interesting thing here is that they add a surface patterning (with some kind of nutrient) to control the growth of cells. (Maybe that is not new either, though.)

Whether society embraces face recognition on a larger scale will ultimately depend on how legislators, companies and consumers resolve the argument about its singularity. Is faceprinting as innocuous as photography, an activity that people may freely perform? Or is a faceprint a unique indicator, like a fingerprint or a DNA sequence, that should require a person's active consent before it can be collected, matched, shared or sold?

Dr. Atick is firmly in the second camp.

Actually these sort of things are also quite easy to exploit. Print a picture of Osama bin Laden on your t-shirt and have the entire police force scared out of their wits.

I saw so many bin laden t-shirts already ... they must have better filters than this

Recently, it was shown that slowly rotating neutron stars exhibit an interesting correlation between their moment of inertia I, their quadrupole moment Q, and their tidal deformation Love number λ (the I-Love-Q relations), independently of the equation of state of the compact object. By exploiting this relation, we can describe quite accurately the geometry around a neutron star with fewer parameters, even if we don't know precisely the equation of state. Side note: I-Love-Q relations? Some inner chuckles in the Fundamental Physicist community.. :)

pretty impressive stuff!

LSTMs: that was also the first thing in the paper that caught my attention! :) I hadn't seen them in the wild in years... My oversight most likely. The paper seems to be getting ~100 citations a year. Someone's using them.

There are a few papers on them. Though you have to be lucky to get them to work. The backprop is horrendous.

A bit of an older story, but I was quite impressed (as a robotics non-expert) by the movement in the video. To me it shows the power of the brain and the "eagerness" (lack of better word) at which it tries to exert some control in the world around it.

Give the Ubermancycle a try?

> As in never ever see sun and daylight :)) Like in the Netherlands you mean?

Tri-phasic sleep rhythm works fine.

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.

A good idea for a card in one of our ACT magic decks!!! In his words AI is "our biggest existential threat" - lol

the "even" in your comment is the key word

Edge.org recently had an interesting piece that ties into all of this recent AI fear mongering: http://edge.org/conversation/the-myth-of-ai

Nine out of 10 workers perform better when listening to music, according to a new study that found 88pc of participants produced their most accurate test results and 81pc completed their fastest work when music was playing.

There's this website: https://www.focusatwill.com/ , which I used for some time. At some point I even subscribed for the paid version (more tracks, control over "intensity" of music). Unfortunately I realized I work the best in complete silence, which is tricky to get - occasionally I put on the white noise http://simplynoise.com/ which works quite well for me.

One article from this weeks Nature outlook articles about cognitive science. You can even play the cognitive game :). The full set of articles is quite interesting!

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?

Simulating the economic state of the Galaxy after the resistance has blown up the Death Stars. See the paper here: http://arxiv.org/pdf/1511.09054.pdf

Love this type of friday afternoon research questions. There is also a now famous scene in the movie Clerks discussing the loss of independent contractors lives as the Death Star was being build.. https://www.youtube.com/watch?v=iQdDRrcAOjA

That analysis is quite crappy and is easily demolished in the video's comments.

no cutting-edge space-related science, but important anyways

The EFF communicate is actually quite inaccurate. This is disappointing from the EFF, though for some part, it is due to the communication from the researchers who "discovered" the attack. PGP itself is not broken, but rather some implementations on some email clients (notably Enigmail, though it was patched several months ago). See https://protonmail.com/blog/pgp-vulnerability-efail/ On the other hand, if you are very keen on security, there is an XSS attack reported on Signal, so… https://thehackernews.com/2018/05/signal-messenger-code-injection.html The *good* recommendation here is actually rather to keep your software stack up to date (surprising, no?) and keep encrypting your emails.