Sound Waves May Have Negative Mass, New Study Reveals

The sound of a sonic boom may produce about the same magnitude of gravitational pull as a 10-milligram weight, a new study finds. Oddly, the findings also suggest the pull is in the opposite direction of the gravitational pull generated by normal matter, meaning sound waves might fall up instead of down in Earth's gravitational field. Image Credit: Uximetc pavel via Shutterstock One might assume these findings are related to Einstein's famous equation E=mc2, which revealed that anything with ene...