Last month, NASA researchers dropped news with potentially huge consequences for space travel and science as a whole: They ran an experiment whose results seem to defy the very laws of physics, and could change how we travel through outer space. Problem is, experts say that it's incredibly unlikely that Isaac Newton is wrong. Instead, the most likely explanation is the team simply made a mistake somewhere along the way
The team was testing a theory that there's a new way to propel satellites, instead of using rockets powered by a limited supply of fuel. So they put a radio antenna in a specially designed, sealed container. Turned on, the antenna bounced 935MHz radio waves (similar to those used by some cell phones) around, and the container apparently moved a tiny, tiny bit. This violates Newton's third law of motion, one of the basic tenets of physics.
Loosely put, Newton taught us that no action can occur without an equal and
opposite reaction. Because there is nothing pushing against the container, propelling it along—no hot gases exploding out the back, for example—it shouldn't be able to move. It's like moving a broken-down car by pushing it from the inside.
If the results hold up, that means there's a way to power vehicles through space without combusting fuel. Today, a satellite's lifetime supply of propellant is limited to how much it can carry. It doesn't need to burn fuel once in orbit, but if a team on the ground wants to tweak its course to avoid space debris or take on a new task, they need to fire it up.
But if radio waves can control the vehicle, that all changes. An antenna could be powered by electricity generated with solar panels. Beyond satellites, this could help humans get to Mars. A consistent source of thrust could accelerate a ship to much higher speeds than traditional propellant-based engines, cutting the time it takes to get from Earth to the red planet.
The NASA team isn't the first to find this result. This is actually the fifth time an independent research lab has tested this kind of device successfully. Not surprisingly, the NASA work, done by researchers David Brady, Harold White, and three other scientists, sparked breathless media coverage claiming the laws of physics has been broken.
Here's the tricky part: The laws of physics are called laws for a reason. It's exceedingly unlikely that shooting off radio waves inside a carefully constructed can is enough to break one of them. It's much more likely there's some error in the experiment, something extremely subtle that no one has noticed yet. It's happened before. In 2011, Italian physicists thought they had discovered neutrinos that could travel faster than light, contradicting Einstein's theory of relativity. After extensive testing, the team realized it had flawed data thanks to a loose fiber optic cable. It's likely that the results of the NASA experiment have a similar explanation.
"Extraordinary claims require extraordinary evidence," says Professor Federico Capasso, the Robert L. Wallace Professor of Applied Physics at Harvard University, quoting Carl Sagan's famous line. "It does no good to science and technology, in fact it hurts its credibility, to go public with such preliminary results that would have to be confirmed by many more experiments designed to convincingly rule out uncontrollable effects or interferences," Capasso says.
John C. Baez, a mathematical physicist at the University of California at Riverside, calls the experiment "graduate-level baloney." He scoffs at the idea that microwaves in a "fancy-shaped can" could violate the law of conservation of momentum.
The legendary physicist Richard Feynman once wrote "for a successful technology, reality must take precedence over public relations, for nature cannot be fooled." A less-forward thinking PR department might say "release the news!" because it makes for great press, but this needs to be carefully proven before it can change the world.
Other labs, including NASA's Jet Propulsion Laboratory in California and at the Glenn Research Center in Ohio, plan to test the system.
It's possible that there is a way to move an object through space using radio waves, and that there's something wrong with Newton's thinking. But it's an extreme long shot, and until we have piles and piles of proof to support it, we can safely assume that something else—maybe a loose cable somewhere—is at work.