Physics Buzz

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Pete Townshend’s gritty guitar style may have helped define The Who’s sound, but it’s also the inspiration behind a recent Physical Review Letter. The wailing—even screeching—so characteristic of his style is a prime example of guitar feedback, which occurs when the amplifier’s noise makes it back to the guitar and causes the strings to vibrate. These vibrations are picked up by the microphone and amplified in turn until the note reaches ear-splitting levels—perfect for a chaotic rock concert:

Not all feedback is deafening, though. Those signs that flash your speed disapprovingly use feedback to encourage you to ease off the gas, and your heating system regulates itself the same way. Without feedback, cells could not maintain homeostasis —but the principle also has frightening implications for climate change

Regardless of the specifics, all feedback loops follow the same general pattern. It all starts when a system release…

Ah, spaghetti. There’s just something about the loveable dish that’s captured popular attention for decades, from the BBC’s spaghetti tree hoax to that famous kiss scene in Lady and the Tramp. But it’s also kept researchers busy with projects like feeding pasta through an MRI machine to see how it cooks, explaining why you just can’t keep sauce from covering your shirt, and building the ultimate spaghetti-snapping machine.

Third-year graduate student Nathaniel Goldberg is one of the latest researchers to try his hand at the floppy dish. He works in Dr. Oliver O’Reilly’s lab at the University of California Berkeley, which models all kinds of things—from plant stems to shoelaces—as slender rods, a one-dimensional mathematical construction. Maybe it’s a case of having a hammer and only seeing nails, but Goldberg can’t help but think about rods anywhere he looks. “The other day, I was looking out the window at all the palm trees and started thinking, Wow, that would be fun to model,” he s…

At this year’s meeting of the American Geophysical Union, over 28,000 earth scientists stormed the streets of San Francisco with their puffy jackets, REI backpacks, and flannels; they were decked out to sit inside and talk about the latest discoveries in earth science (and drink over 4,500 cups of coffee). In one room, however, a small group of scientists were talking about science on planets a bit further away.

Reader, they were talking about aliens.

Finding life on other planets is no easy task, and it’s not likely we’ll find tiny little green dudes. Even finding microbes would be difficult. It’s possible that planets in our solar system had life long ago, but changing conditions have rendered them uninhabitable.

We don’t even know how life is created on earth, so how are we supposed to see how it created on other planets?

So, instead of looking for life itself, we need to look for signs. Looking for traces of life on other planets is not as easy as looking for fossils, footprints…

Car seats save lives, but ultimately the best way to protect passengers is to prevent crashes from happening in the first place. Prevention has been tackled from many different directions–insurance incentives for defensive driving, legal consequences for reckless driving, backup cameras, more effective headlights, reduced speed limits, and safer intersections, among others. But it’s still not enough.

One of the more recent prevention approaches is outfitting cars with advanced collision warning systems. By integrating radar, laser, camera, and sometimes sonar technology, these systems use math and physics to determine the relative speed between the car and objects in its path. If a system senses that the car is approaching a slow-moving vehicle or stationary object too quickly, it beeps, vibrates, or otherwise prompts the drivers to react.

Drivers don’t always react appropriately or quickly enough though, so many car manufacturers are now combining warning systems with automatic brak…