Scientists Create Invisible Tube That Moves Matter With Sound

Scientists just turned science fiction into reality by creating an invisible tube that levitates and guides matter using nothing but sound waves.

Researchers at the University of Helsinki, working with teams from Spain and Michigan, built a device that looks like pure magic. Their prototype uses 256 tiny speakers arranged in a cylinder to create an invisible pathway made of ultrasonic sound waves. Water flows through mid-air along this invisible tunnel, appearing to float as if by sorcery.

The tube works by emitting sound waves at 40 kilohertz, well above what human ears can detect. By carefully timing these waves, the team creates an acoustic field that gently pushes materials along a specific path. The best part? They can bend and redirect the flow simply by adjusting the speaker settings, no physical movement required.

Professor Ari Salmi, who led the project, couldn't hide his amazement. "Of all the experimental setups I have seen, I would say this is the closest thing to magic," he says.

The team started with a simple problem: how to clean substances stuck inside regular pipes. Then they had a brilliant thought. What if they could eliminate the pipe walls entirely so nothing could stick in the first place?

Their solution guides more than just water. The researchers successfully directed powders into different containers, steered mist and gas streams, and even controlled the path of electrical discharges and plasma. Previous acoustic systems could only suspend individual particles or droplets, but this prototype handles continuous flowing streams.

The current version measures just 8 centimeters long and uses about as much electricity as an old incandescent light bulb. Yes, it takes 256 speakers to create that short invisible tunnel, but the researchers believe they can connect multiple modules to build much longer pipes.

Why This Inspires

This technology could transform how we handle dangerous or delicate materials. Corrosive chemicals that eat through metal pipes could flow safely through sound. Ultra-sensitive pharmaceuticals that get contaminated by contact with container walls could travel without touching anything solid.

The ability to redirect flows electronically opens up precise delivery possibilities that physical pipes simply cannot match. Need to send material to a different location? Just reprogram the speakers instead of rebuilding your entire pipeline system.

There's a fun quirk worth mentioning. While the ultrasound operates silently to human ears, the acoustic intensity at the tube's center equals standing next to continuous gunfire. Outside the device, it's comparable to a jet engine. Thankfully, at 40 kilohertz, we hear absolutely nothing. Just keep the family dog away from the lab.

The research appears in the journal PNAS, marking another step toward contactless transportation systems that once existed only in superhero movies.