All articles tagged with #acoustics
The article explores popular 19th-century science experiments with sound, highlighting Ernst Chladni's work with Chladni figures that visually demonstrate sound waves, and discusses how Victorian society engaged in hands-on acoustic experiments as both entertainment and education.
In the 1980s, researchers in New Zealand recorded mysterious quack-like sounds in the South Fiji Basin, dubbed "Bio-Duck," which were initially thought to be non-biological. However, further analysis suggested they might be a form of communication between marine animals, possibly Antarctic Minke whales, although this remains unconfirmed. The sounds were recorded using a hydrophone array, revealing a pattern of alternating "speakers," suggesting a conversational nature. This research was presented at the 187th Meeting of the Acoustical Society of America.
Apple's acoustics team, responsible for audio technology in AirPods, HomePods, and other devices, will undergo leadership changes as longtime VP Gary Geaves steps down and is replaced by Ruchir Davé. The team has been working on spatial audio and is currently reporting to Matt Costello. Geaves will stay on as an advisor as he prepares to retire, and the team is expected to release updates to the AirPods lineup this year, with rumors of AirPods 4 and new AirPods Max. Additionally, iOS 17.4 is set to bring new features to the iPhone, including major App Store changes in the EU and Apple Podcasts transcripts.
Researchers have successfully cooled sound waves in an optical fiber to near quantum ground state using laser cooling and stimulated Brillouin scattering, reducing thermal noise and potentially bridging classical and quantum mechanics. This breakthrough paves the way for utilizing long acoustic phonons in quantum technologies, with implications for quantum communications and future quantum technologies. The study, published in Physical Review Letters, demonstrates a significant reduction in temperature of a sound wave in an optical fiber, marking a promising step towards reaching the quantum ground state in waveguides and gaining deeper insights into the fundamental nature of matter.
The Pirunkirkko cave in Finland, also known as the Devil's Church, has gained a reputation for its alleged contact with the spirit world. Researchers from the University of Eastern Finland have discovered that the cave has a unique resonance caused by a standing wave between its smooth parallel walls. This resonance amplifies and lengthens sounds at specific frequencies, creating a tone at 231 Hz that stays audible for about one second. Visitors claim to feel the presence of a spirit due to this subtle resonance, which is rare in natural environments.
Researchers have developed a novel method to deflect laser beams using air alone. By modulating the air with sound waves, an invisible grating is created that changes the direction of the laser light without contact. This technique offers precise control over laser light and preserves its original quality, making it promising for high-performance optics. The initial laboratory tests achieved a redirection efficiency of 50%, with potential for higher efficiencies in the future. The researchers see applications in material processing, fusion research, and particle accelerators, where strong laser beams can damage traditional optical elements. The technique can also be extended to other optical elements and wavelengths, opening up new possibilities in optics.
Researchers have discovered a second wave of topological phenomena in photonics and acoustics, following the discovery of topological insulators in condensed matter physics. These topological phenomena involve the manipulation of waves in materials to create robust and protected transport of light and sound. The discovery has potential applications in areas such as communication, sensing, and imaging.
Archaeologists have discovered a collection of 12,000-year-old flutes made from bird bones at a prehistoric site in Israel. The flutes, which were carved by the Natufians, the last hunter-gatherers in the Levant, mimic the calls of certain birds of prey. The Natufians were methodical in selecting small bones to create high-pitched sounds similar to those made by Eurasian sparrowhawks and common kestrels. The flutes are the oldest sound instruments imitating bird calls in the world and provide evidence of the Natufians' relationship with symbolically valued birds of prey.
Archaeologists have discovered a collection of 12,000-year-old flutes made of bird bones at a prehistoric site in Israel. The flutes, which mimic the calls of certain birds of prey, were likely used for hunting, music, or even communication with the birds. The Natufians, a cultural group that were the last hunter-gatherers in the Levant, created the flutes by selecting small bones to produce high-pitched sounds similar to those made by falcons. The flutes are the oldest sound instruments imitating bird calls in the world and demonstrate the Natufians' knowledge of acoustics and technical precision.