CLOSE

Scientists Created a Water Tractor Beam

Tractor beams have long been a science fiction fantasy—a magical force that attracts objects from a distance, like an alien’s spaceship sucking up its earthling specimens. We’re not quite that advanced, but physicists at The Australian National University have created a “tractor beam on water” that makes floating objects move wherever they are directed.

The group, led by Professor Michael Shats, started with a ping pong ball. Placing it in a small pool, they created waves using a thin, cylindrical device with suction cups on the bottom. When the device vibrates up and down, these cups come in contact with the water, creating waves. Different wave frequencies and sizes, along with different cup shapes, create different kinds of currents. Some pulled the ball inward, some pushed it outward.

Dr. Horst Punzmann, from the Research School of Physics and Engineering, said the team even found a way of “creating waves that can force a floating object to move against the direction of the wave.”

This doesn’t sound like rocket science. It seems quite obvious that waves make floating objects move, right? But actually, what propels floating objects aren’t the waves themselves, it’s the currents they create. Never before have we identified the precise wave patterns that make an object go one way or another, or how to replicate them. “It’s one of the great unresolved problems, yet anyone in the bathtub can reproduce it,” Punzmann said. Interestingly, there’s still no mathematical theory to explain why these experiments work. That said, this new knowledge could help us clean up oil spills and ocean trash, or retrieve drifting boats.

"The applications could be numerous," Shats said. A paper documenting the findings is featured in the journal Nature Physics.

Original image
arrow
language
The Evolution of "Two" in the Indo-European Language Family
Original image

The Indo-European language family includes most of the languages of Europe as well as many languages in Asia. There is a long research tradition that has shown, though careful historical comparison, that languages spanning a huge linguistic and geographical range, from French to Greek to Russian to Hindi to Persian, are all related to each other and sprung from a common source, Proto-Indo-European. One of the techniques for studying the relationship of the different languages to each other is to look at the similarities between individual words and work out the sound changes that led from one language to the next.

This diagram, submitted to Reddit by user IronChestplate1, shows the word for two in various Indo-European languages. (The “proto” versions, marked with an asterisk, are hypothesized forms, built by working backward from historical evidence.) The languages cluster around certain common features, but the words are all strikingly similar, especially when you consider the words for two in languages outside the Indo-European family: iki (Turkish), èjì (Yoruba), ni (Japanese), kaksi (Finnish), etc. There are many possible forms two could take, but in this particular group of languages it is extremely limited. What are the chances of that happening by accident? Once you see it laid out like this, it doesn’t take much to put *dwóh and *dwóh together.

Original image
arrow
infographics
Beyond Plumbing: 19 Other Jobs on Mario's Resume
Original image

Nintendo made news this week by subtly announcing that Mario is no longer a plumber. In fact, they're really downplaying his whole plumbing career. On the character's Japanese-language bio, the company says, "He also seems to have worked as a plumber a long time ago."

But Mario has always had plenty of jobs on the side. Here's a look at his resume:

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios