Jonas Zmuidzinas’s new favorite saying is a phrase that’s been running through his mind a lot lately. A physicist at Caltech who develops instrumentation for use in astronomy, he spends an inordinate amount of his waking hours thinking about noise—but not in the way you might expect. For the average person, thinking about noise might mean trying to ignore the loud neighbors on a Sunday morning or using sound-cancelling headphones on a flight full of babies.
But for many scientists and engineers, a broader definition also assigns the term to the fluctuations in a measured signal that can obscure or reduce its clarity. “For people like myself who build instruments and detectors, noise is at the heart of what we do,” says Zmuidzinas. That’s because in engineering, for example, fluctuations, or noise, can arise from the random motions of atoms or electrons, and can manifest as heat or electronic static. And that can lead to malfunctioning machines. A clearer understanding of noise sources and ways to minimize it in circuits can lead to more efficient microchips and to telescopes that are capable of probing structures in the universe that were previously beyond reach.
As we explored in our Spring 2015 article Good Vibrations, noise can beneficial in certain scientific contexts but is far less welcome in more mundane situations.
KPCC’s AirTalk program recently featured an interview with Brendan Farrell, a former Caltech postdoctoral student in computing and mathematical sciences, about his Kickstarter campaign that aims to map the noise levels of Southland communities. Farrell got the idea for the site, called HowLoud, after he went seeking a new apartment in a quiet location — only to realize there were no good, accurate data on how quiet a given apartment might be.
HowLoud is an attempt to provide that information: it seeks to scientifically quantify noise levels in the region and also provide an easy way for consumers to compare various locations. The system quantifies noise from traffic, airports, and businesses on a 100-point scale, with quieter areas receiving higher scores.
As Farrell explained on AirTalk, “We wanted to create a user-friendly consumer tool. We’ve taken a lot of the traditional acoustical engineering tools and used [computer modeling] on a massive scale, so we have a huge 3-D model of all of Los Angeles County and Orange County. And we have the traffic in there and just use physics to propagate the noise this traffic creates throughout the region.”
The HowLoud Kickstarter project—run by a team including Farrell and four mapping and mathematical modeling experts—has been featured in several media outlets and is well on its way to reaching its goal.
The rest of the KPCC interview can be found online.