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The weird physics of plant-based milks is only just coming to light

Karmela Padavic-Callaghan — Mon, 30 Mar 2026 06:00:39 +0000

Experiments on different kinds of milk have revealed that many plant-based milks are non-Newtonian fluids

Electrons inside graphene have been pushed to supersonic speeds

Karmela Padavic-Callaghan — Wed, 08 Oct 2025 17:18:35 +0000

Making electrons flow like a liquid is difficult, but inside graphene researchers forced them to move so fast that they created dramatic shockwaves

These centuries-old equations predict flowing fluid – until they don’t

Tom Crawford — Tue, 05 Aug 2025 17:00:37 +0000

We use the Navier-Stokes equations every day, for applications from building rockets to designing drugs. But sometimes they break – and we don’t know why

Mathematicians solve 125-year-old problem to unite key laws of physics

Karmela Padavic-Callaghan — Fri, 14 Mar 2025 16:00:23 +0000

Can one single mathematical framework describe the motion of a fluid and the individual particles within it? This question, first asked in 1900, now has a solution that could help us understand the complex behaviour of the atmosphere and oceans.

Jets of liquid bounce off hot surfaces without ever touching them

Karmela Padavic-Callaghan — Tue, 12 Nov 2024 18:51:32 +0000

Droplets of fluid have been known to hover above a hot surface, but a new experiment suggests the same can happen to tiny jets of liquid too

Freak waves may be more dangerous than we thought possible

Christa Lesté-Lasserre — Wed, 18 Sep 2024 15:00:35 +0000

Experiments in a state-of-the-art wave tank suggest we have underestimated the potential size and power of rogue waves and the risk they pose to offshore infrastructure

How strange ice could form in the extremely hot interiors of planets

Karmela Padavic-Callaghan — Wed, 28 Aug 2024 21:21:39 +0000

In an experiment simulating what happens deep in the interiors of planets, scientists have found that liquid can be compressed into ice crystals – even at extremely high temperatures

‘Running of the bulls’ festival crowds move like charged particles

Karmela Padavic-Callaghan — Tue, 19 Mar 2024 10:00:18 +0000

Researchers have studied the movements of thousands of people waiting for the opening of the San Fermín festival and found they behave like electrons circling in a magnetic field

Magnetic particles turn water droplets into tightrope-walking acrobats

Karmela Padavic-Callaghan — Wed, 28 Feb 2024 15:00:53 +0000

A new technique can precisely steer drops of water around obstacle courses and into chemical reactions

Jonathan Knowles/Getty Images

Putting tiny magnetic particles inside ordinary water droplets can turn them into liquid acrobats – the droplets can climb steps, leap over obstacles and jump-start chemical reactions. This level of control could be useful in drug delivery or to make more complex lab-on-a-chip technologies.

at Sun Yat-sen University in China and his colleagues made a surface with tiny grooves and covered it in a varnish that is superhydrophobic, or nearly impossible to wet. They knew water droplets sitting on top of such grooves can spontaneously jump up because of the pressure difference between a droplet’s bottom, which is deformed by the small channel, and its rounder and less restrained top.

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Liquid robot can split into tiny droplets and reform into a blob

The researchers wanted to create this pressure difference on demand. They added a tiny magnetic particle into each droplet and placed an electromagnet underneath the groove. When they turned on the electromagnet, it pulled the particle – and therefore some of the droplet – into the groove. When they switched it off, the droplet’s shape rebounded and it flew upwards as if flying from a slingshot.

With this technique, the team made liquid droplets hop up millimetre-scale stairs and over miniature obstacles. The researchers even steered a droplet into a narrow space between two wires, thus connecting a circuit and lighting a light bulb.

at Chongqing University in China says this is a creative way to take control of pressure-based droplet jumping, and it could be a valuable tool for precisely transporting droplets of chemicals.

In one experiment, researchers caused a droplet to jump into and mix with a liquid chemical sample under a microscope lens, enabling them to watch the resulting chemical reaction from start to finish. In another, they made two droplets mix with a third inside a closed box, remotely starting a reaction that would have been ruined if a researcher had needed to open the box and let air in.

Such precise chemical control has applications for drug delivery. Huang hopes the technique will also advance “lab-on-a-chip” technologies, efforts to miniaturise complex biochemistry experiments that usually require lots of space and glassware. He proposes “lab-on-stacked-chips”, where droplets vertically jump between levels to allow many reactions to happen in parallel.

Journal reference:

ACS Nano

Stunning slo-mo videos show how insects survive raindrop collisions

Chen Ly — Mon, 22 Jan 2024 20:00:54 +0000

Water striders are tiny insects that have a surprising ability to survive impacts with raindrops dozens of times heavier than they are. Slow-motion videos of them getting smashed by water have revealed the tricks they use to avoid getting crushed – including how they can shoot into the air aboard a water jet and somersault off before landing. As their name suggests, water striders can be found walking across the surfaces of ponds, lakes and rivers around the world. They have long legs covered in microscopic hairs that trap air, helping the insects to float on water.

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Fire ants form rafts that have weird properties when stretched

“I saw them skating around the water one day, and I thought, ‘what do they do when it rains?’” says at the University of Tennessee. Raindrops can weigh more than 40 times as much as adult water striders. “How do they survive? Are they submerged, or are they ejected into the air?” he added. To investigate, Dickerson and his colleagues put some water striders into a glass aquarium filled with water, bombarded them with droplets and recorded the critters’ reactions with slow-motion videos. The researchers noticed that, when a raindrop collided with an insect on the water’s surface, the bug initially remained unscathed, as a result of its low density. However, it did get dragged down into the resulting impact crater. The collapse of the crater then shot a jet of water back up above the surface – and the insect went with it. In a handful of cases, the team witnessed water striders jumping away from the water jet before it fell back to the surface. “It was pretty neat; we saw some backflip off that jet,” says Dickerson. But if the water striders couldn’t escape the jet of water, they would get sucked back down again. Luckily, their hairy, water-repelling legs allowed them to float and swim back to the surface. “It’s the equivalent of us getting hit by a car, and they survive it – and undergo this quite acrobatic journey in the process, in some cases,” says Dickerson.

Journal reference

Proceedings of the National Academy of Sciences