Physics Buzz

Most of us are familiar with the screeching noise packing tape makes when it's peeled off a box, as well as the frustration of failing to cleanly remove a label from a new purchase. It turns out that the jerky stop-and-go motion we experience when peeling tape occurs at a microscopic level as well.

When you think of an aerodynamic car, what comes to mind? Smooth curves, sharp points, images of smoke streaming over surfaces in a wind tunnel—but what if we didn’t have to change something’s shape to help it cut through the air more efficiently? That’s the idea behind a new experiment reported in Physical Review Fluids, in which scientists showed that adding nozzles which shoot precisely timed jets of air can substantially cut a vehicle’s drag profile, potentially improving efficiency and gas mileage.

The sound of a sonic boom may produce about the same magnitude of gravitational pull as a 10-milligram weight, a new study finds. Oddly, the findings also suggest the pull is in the opposite direction of the gravitational pull generated by normal matter, meaning sound waves might fall up instead of down in Earth's gravitational field.

Nobel Laureate Samuel Ting laughed when I asked where all of the high energy electrons that hit his particle detector were coming from. “The data has just been published three days ago,” he told me, hinting at the depth of the mystery and the virtue of patience. “The most important thing is that none of our results can be explained by current models.”

For the past two decades, scientists have constructed a variety of experiments, including cryogenic detectors and tanks of liquid xenon, around the world in hopes of spotting the scantest signs of elusive dark matter particles. But time and time again, they've come up empty-handed. Now a team of scientists propose a completely different approach.

In an increasingly digital world, it’s small wonder that we’re constantly searching for ever-more-sophisticated ways to interact with photographs and images: designers scan a 3D prototype and import its dimensions into a computer; medical programs image an internal organ and delineate the tumor to be removed; robots avoid drop-offs by recognizing the shapes that stairs make on their detectors; teenagers transform their selfies into what appears to be a pencil sketch.

The size of a small city, the target asteroid is imposing. The cracks and craters on its surface reflect years of wear in the extreme and dangerous environment of deep space.

Finding the next miracle material can be a tedious process. Thomas Edison and his fellow researchers famously tested thousands of materials before finding the right one for making lightbulb filaments. The search for superconductors, and in particular materials that can sustain superconductivity up to room temperature, is perhaps a modern-day equivalent.

The GRAPES-3 muon telescope in Ooty, India was designed to study the cosmos—events that took place millions of years ago at distances that confound the human imagination. What researchers didn’t expect was that it would also shed light not just on cosmic history, but on a mystery much closer to home: the massive power hidden in a thundercloud.