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Planetary migration poses a serious challenge to theories of planet formation...When multiple planets stir the disk, our simulations yield the new result that large-scale migration ceases. Thus, growing planets do not migrate through planetesimal disks....Although migration through a gaseous disk is an important issue for the formation of gas giants, we conclude that migration has little impact on the formation of terrestrial planets.

Cheap and scalable invisibility cloaks being developed. The setup is so trivial that I would almost call it a "trick" (as in "Magicians trick"): 6 prisms of n=1.78 glass. Nontheless, it does the job of cloaking an object at visible wavelengths and from several directions.

Is this really new? I don't know, but I know that the original idea of cloaking was pretty different. When cloaking as an application of transformation optics became popular people tried to make devices that work for any incidence angle, any polarization and in full wave optics (not just ray approximation). This is really hard to achieve and I guess that the people that tried to make such devices knew exactly that the task becomes almost trivial by dropping at least two of the three conditions above.

I think it is very easy to call something trivial when you're not the one who invested considerable time (5 min in my case) to design a cloaking device and fill the coffee mugs with water... Also, I did not really violate that many conditions: true I reduced the number of dimensions in which the device works to 1 (as opposed to the 2 dimensions of many metamaterial cloaks). However the polarization should not be affected in my setup as well as the wave phase and wave vector (so it works in full wave optics) - apart maybe from the imperfect lens distortion, but hey I was improvising.

schools of fish => schools of wind turbines

A group of researchers from Austria have sent twisted beams of light across the rooftops of Vienna. It is the first time that twisted light has been transmitted over a large distance outdoors, and could enable researchers to take advantage of the significant data-carrying capacity of light in both classical and quantum communications. Although the data rate is not very high, it could offer a way to provide unhackable data links via space. Would provide an edge over terrestrial fibre optics?

Mitsubishi Heavy Industries said Friday that it has succeeded in transmitting 10 kW of power through 500 m. An announcement that comes just after JAXA scientists reported one more breakthrough in the quest for Space Solar Power Systems (http://phys.org/news/2015-03-japan-space-scientists-wireless-energy.html). One step closer to Power Generation from Space/

from the press release (https://www.mhi-global.com/news/story/1503121879.html) "10 kilowatts (kW) of power was sent from a transmitting unit by microwave. The reception of power was confirmed at a receiver unit located at a distance of 500 meters (m) away by the illumination of LED lights, using part of power transmitted". So 10kW of transmission to light a few efficient LED lights??? In a 2011 report (https://www.mhi-global.com/company/technology/review/pdf/e484/e484017.pdf), MHI estimated this would generate the same electricity output as a 400-megawatt thermal plant - or enough to serve more than 150,000 homes during peak hours. The price? The same as publicly supplied power, according to its calculations. There are no results to boost these claims however. The main work they do now is focused on beam steering control. I guess the real application in mind is more targeted to terrestrial applications, eg wireless highway charging (http://www.bbc.com/future/story/20120312-wireless-highway-to-charge-cars). With the distances so much shorter, leading to much smaller antenna's and rectenna's this makes much more sense to me to develop.

Paper: https://arxiv.org/abs/1806.02404