Fluid

Harvard engineers have created a strange new “metafluid” – a liquid that can be programmed to change properties, like its compressibility, transparency, viscosity and even whether it’s Newtonian or not.

In fluid dynamics, hard science often comes with dazzling aesthetic beauty – a fact the American Physical Society highlights annually with a photo/video contest. Here are this year's winners – equal parts fascinating, hypnotic and visually stunning.

We’re willing to bet you’ve never given much thought to how bugs urinate, but even if you did you probably wouldn’t imagine them using butt-based pinball paddles to flick drops of pee at 40 G’s, using physics never before seen in nature.

A large percentage of a building’s energy usage is consumed by heating and cooling, but a new dynamic shading system could help. Inspired by the skin of krill, the system uses cells of blooming pigment that can block light on demand.

Researchers at MIT have observed “electron whirlpools” for the first time. The bizarre behavior arises when electricity flows as a fluid, which could make for more efficient electronics.

Bubbles aren’t known for their long lifespans, usually only giving a few seconds of childlike joy before they pop. A team of French scientists has developed a new way to make bubbles last longer, with the record holder surviving for well over a year.

It may be a bit gross, but mucus plays a key role in our bodies. Now, an MIT team has managed to create an artificial version of the stuff, and shown that it’s an effective antimicrobial – even more so than real mucus.

Nobody likes needles – at best they’re an unpleasant means to an important end. Microneedle patches could be a painless alternative, and now researchers have developed a way to use them to detect biomarkers at much lower levels without drawing blood.

Curtains or blinds might eventually get the flick in favor of smart windows. Now a team of engineers has demonstrated a new design. Dubbed Large-Area Fluidic Windows (LaWin), the system uses iron particles suspended in liquid to block sunlight at different levels, and harvest its heat energy.

If you pushed a ball with negative mass, it would move towards you. It might be hard to picture, but according to Newtonian physics it should be possible. Now a team at Washington State University has demonstrated the phenomenon in practice, creating a fluid that has the properties of negative mass.

Thanks to gravity, fluids flow downwards following the path of least resistance. Now researchers at Brandeis University have mixed biological molecules into a substance that marks the first steps towards developing a self-propelling liquid, that could flow free of human or gravitational influence.

An unusual state of matter, first theorized almost 50 years ago, has been created in experiments for the first time. Say hello to the supersolid, a state where atoms simultaneously exhibit a crystalline structure but still flow like a frictionless fluid.