With a title like "Big Bang" you'd figure there'd be some crashing noise behind it. But the Big Bang that birthed our universe wasn't some ear-splitting, explosive sound. Instead, it was more akin to a robotic humming. And, it was inaudible to the human ear.
We know this because a physicist at the University of Washington named John Cramer decided to re-create the sound of the Big Bang. He used data collected by a satellite sent to inspect the cosmic microwave background -- electromagnetic radiation remnants from the Big Bang. He fed the data into a computer program, which converted it into sound. But the sound was so low, so bass, it was inaudible to humans until Cramer boosted its frequency 100 septillion times!
The Big Bang "sounded somewhere between a video game character dying, or like an old-school computer powering down," says Will Pearson in a recent episode of the podcast Part Time Genius that focuses on the world's strangest, loudest and most irritating sounds. Will co-hosts the podcast with Mangesh (Mango) Hattikudur.
While the Big Bang likely wasn't an impressively loud sound, it was a long one. For the first 100,000 to 700,000 years after it was created, the universe was denser than the air on Earth. This meant sound waves could travel through it. As the universe cooled and expanded, the sound wavelengths stretched, which made sounds get lower. The humming from the Big Bang continued for those hundreds of thousands of years until the universe grew so large that the sound faded away completely. (You can hear what the Big Bang sounded like by listening to the Facebook post below.)
Will and Mango talked about more than just what the Big Bang might have sounded like, though. They also discussed some of the world's most repulsive sounds. According to a 2007 U.K. study, vomiting was tops, followed by microphone feedback and crying babies. Two others cracking the top 10 were, strangely, a squeaky seesaw (No. 5) and an argument heard on a soap opera (No. 9).
Knowing about these annoying sounds isn't just interesting, it also has practical implications. For years, mass-transit sites, convenience store owners and others have played classical music to deter criminals, the homeless and crowds of teens. And in 2003, Will says, the BBC reported U.S. interrogators were blasting tunes from Metallica and Skinny Puppy, as well as the "Barney" TV show theme song, to get captives to talk. (Skinny Puppy sent the Department of Defense a bill for royalty payments when the band learned about this.)
Of course, sounds can be incredibly soothing and positive, too. Think of the delicate pattering of a gentle rain, a baby giggling and a steak sizzling on the grill. Certain sounds also evoke memories. Hear a specific song, for example, and it might transport you back to a special occasion.
But, likely, it's not the "Barney" theme song.
To learn more, including what makes some noises so annoying, listen to "What are the Strangest, Craziest Sounds in the Universe?"