Everybody has that one neighbor they'd like to have a volume control for. Especially when the air is crisp and sweet and all you want to do is throw the windows open and enjoy the day. Now, impossible as it might seem, you can do both at the same time.
Developed by South Korean team Sang-Hoon Kima and Seong-Hyun Lee, a new window has taken shape which can actually rip the sound right out of the air. The breeze blows right into your home, but the sound traveling with it is blocked. To pull of their apparent magic trick, Kima and Lee relied upon clever application of some little known properties of sound: a negative bulk modulus and cleverly-placed holes.
All materials have a bulk modulus. The term basically refers to the amount something resists pressure. So, when that number goes negative, the pressure sound exerts on your surface is dissipated exponentially. And then there are those holes. By drilling precisely-placed holes in the same negative bulk material, Kima and Lee found that they could maximize the diffraction of sound waves. In layman's terms, they made the sound bounce around on this sound-killing surface a ton.
What's even cooler than a window that kills all the sound that comes into contact with it is one that can be designed to kill only the "bad" noise. And that's something which the engineers behind the new window are working on as well. What do we mean "bad" noise, you ask. Well here's how Kima and Lee describe it: "for example, if we are in a combined area of sounds from sea waves of low frequency and noises from machine operating at a high frequency, we can hear only the sounds from sea waves with fresh air."
So you can have your ocean breeze, the rolling waves and block out Marty McFly's guitar practice? We're sold. When these awesome windows hit the market, you can be sure that Kima and Lee will have at least one client right off the bat.