Flash Physics is our daily pick of the latest need-to-know developments from the global physics community selected by Physics World‘s team of editors and reporters
Flytrap soft robot catches prey
A Venus flytrap’s autonomous insect-catching ability has been replicated by a tiny soft robot. To create the device, Arri Priimägi and team from Tampere University of Technology in Finland attached a strip of light-responsive liquid-crystal elastomer to the tip of an optical fibre. Mimicking the Venus flytrap’s head, the strip of elastomer is about 10 mm long, 1 mm wide and 20 μm thick. It contains layers of ordered molecules that have a different orientation in each layer – those in the “insect-facing” layer are horizontal while those on the opposite side are vertical. The molecules in between are at an intermediate angle. When light is shone on the elastomer, the molecular alignment becomes random. This causes the insect-facing layer to contract and the other side to expand – in other words, the strip of elastomer bends like a flytrap closing. Usually a light-responsive elastomer requires external illumination, but by attaching the strip to an optical fibre, Priimägi and colleagues integrated a light source. Light shone through the optical fibre and elastomer creates a cone of illumination. When an object such as an insect enters this field of view, light is reflected back in the direction of the elastomer. This thereby triggers the elastomer to bend and close around the object. To release the object, the light is simply turned off. The autonomous device, presented in Nature Communications, could be used for intelligent micro-robotics as well as handling delicate small objects.
Could huge doughnut-shaped “planets” exist?
Huge doughnut-shaped objects made from vapourized rock could be orbiting stars other than the Sun. That is the conclusion of Simon Lock of Harvard University and Sarah Stewart at the University of California, Davis, who have done calculations that suggest a new type of planetary object called a synestia could form when rocky planets collide with each other. Such an object would be about four times the diameter of Saturn’s rings and would comprise a ring of rapidly rotating vapourized rock. It would resemble a doughnut, but instead of having a hole in the middle, a synestia would have a dense planet-like object at its centre. Lock and Stewart say a synestia would form when the debris from planetary collisions was both very hot and carrying large amounts of angular momentum. They also suggest that most planets could have been synestias early in their lifetimes. Small planets such as Earth would only spend a few hundred years in this phase before condensing into solid objects. However, larger or hotter objects such as gas-giant planets or even small stars could spend much longer times as synestias. Although synestias have not been observed, the calculations could encourage astronomers to look for huge doughnut-shaped objects alongside rock and gaseous exoplanets. The research is described in the Journal of Geophysical Research: Planets.
European Union dishes out £55m for UK physics
UK physics received £55m in 2014/2015 from the European Union (EU) according to a report by Technopolis Group – an independent policy research organization. Commissioned by the UK’s four national academies – the Academy of Medical Sciences, the British Academy, the Royal Academy of Engineering and the Royal Society – the report looked at how reliant UK research is on EU funding. The EU’s Seventh Framework Programme, which ran from 2007 to 2013, provided UK organizations with around €7bn and its successor – Horizon2020 – is providing around €1.1bn per year. This figure amounts to more than 10% of total UK government support for research and is around 5% of the UK’s gross domestic expenditure on R&D. The report finds that UK universities received around £725m in research grants from EU government bodies in 2014/2015, of which £55m was received by both physics and chemistry while the biosciences got £90m. As the top 10 UK universities receive almost half the £725m funding, the report warns that this will be “difficult to replace” after the UK leaves the EU in 2019.