A Brief History of Noise

January 7, 2016

It can sometimes feel like the world is very noisy—from planes arcing loudly through the sky to the unceasing buzz of your cellphone. But it wasn’t always this way. There weren’t always sounds being transmitted through the air, and there weren’t always animals and humans around to make sounds. And there certainly weren’t always technologies around to record sounds, in basements and fancy studios and subway cars.

Sound has a history, from the first sound ever, to the first sound heard by an animal, to the first recorded by a human being.

The first sound ever was the sound of the Big Bang. And, surprisingly, it doesn’t really sound all that bang-like. John Cramer, a researcher at the University of Washington, has created two different renditions of what the big bang might have sounded like based on data from two different satellites.

During the first 100 to 700 thousand years after the Big Bang, the universe was far denser than the air on Earth, which means that sound waves could indeed move through it. (It’s not true that sound needs air to move, it simply needs a medium dense enough to propagate the waves.) But the sound would have been such a low frequency that, had humans been around at the time, we couldn’t have heard it. For listening purposes, Cramer has increased the frequency of the sound to fall into the range that humans can actually detect.

In 2001, Cramer wrote a column called “BOOMERanG and the Sound of the Big Bang” for the publication Analog Science Fiction and Fact. In the column, he talked about an experiment that had recently recorded the temperature of the cosmic microwave background—the radiation left over from the Big Bang. In the column, he called the data the “sound of the Big Bang.”

In 2003, Cramer got an email from a woman whose 11-year-old was doing a school project on the Big Bang. He had read Cramer’s column, and wanted to know if there was actually a recording of the “sound of the Big Bang” that he could play for his class. There wasn’t, but it got Cramer thinking. “The idea of synthesizing the Big Bang sound fascinated me,” Cramer writes on his website. “It ran around in my head for a day or so, and I had a growing desire to hear just what the Big Bang sounded like.”

So he made it. Using data from a NASA satellite called WMAP, he plugged in the frequency spectrum from the Big Bang into some software to turn the data into a sound file. “When I ran the program for the first time and the sound started in my office, our two male Shetland Sheepdogs, Alex and Lance, came running into the room, barking with agitation,” Cramer writes.” Here’s what it sounds like:

In 2013, Cramer made a new sound file using new data, this time from the European Space Agency’s Planck Mission. Here’s what that one sounds like:

Since before the Big Bang there was no universe, it seems safe to say that this is likely the first sound in the universe. But what was the first sound ever actually heard? To figure that out, we need to figure out which organism was first able to hear.

The first organisms to be able to hear things were probably the bony fishes, which appeared on this planet about 400 million years ago. These fish developed the ability to sense vibrations by adapting an organ they used to balance themselves in the water called the “balance labyrinth.” Eventually, that labyrinth got more and more complicated, developing curves and features that would, a long time later, develop into a proto-cochlea.

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