The Big Bang sounded more like a deep rumble, according to a new analysis of the radiation left over from the massive explosion
The Big Bang sounded more like a deep rumble, according to a new analysis of the radiation left over from the massive explosion.
Physicist John Cramer from the University of Washington in Seattle created audio files (link - at the bottom of the news) of the event, which can be played on a personal computer. "The sound is quite similar to the sound of a jet plane flying a hundred feet above your house in the middle of the night," he says. Tremendous sound waves propagated through the hot, bubbling matter that filled the universe shortly after the Big Bang. These pressed and stretched the material. In doing so, they heated the compressed areas and cooled the loose areas. Although the universe has expanded and cooled since then, the sound waves left their mark on the radiation left over from the big bang, known as the cosmic background radiation, in the form of temperature differences.
An eleven-year-old boy, who wanted to know what the Big Bang sounded like for a school project, prompted Kramer to recreate the noise, last heard 13.7 billion years ago. To produce the sound, Kramer used information from NASA's Wilkinson study on the non-uniformity of microwave radiation. The research started in 2001, and it measures tiny temperature differences between different parts of the sky. From these changes he could calculate the frequencies of sound waves propagating in the young universe in its first 760,000 years, when it was about eighteen million light years in size. At that time the frequency of the sound waves was too low to be heard. To overcome this, Kramer had to increase the frequencies 100,000 billion billion times. Nevertheless, the loudness of the sound and its pitch reflect the events in the ancient universe. During the hundred-second recording, the frequencies decrease, because the sound waves stretched with the expansion of the universe. "It (the sound) turns into a bass," says Kramer.
to hear the sound file
