Waves, sound & harmonics

Sound and vibration in science and technology. Each topic lists only known properties from the cited papers.

• Acoustic cell patterning (standing waves)
  1 study · Standing sound waves, like the patterns sand makes on a vibrating plate, can line up living cells into tissue-like arrangements.
• Acoustic levitation and acoustic tweezers
  2 studies · Sound waves can hold, move and spin tiny objects, from vesicles to whole small organisms, without touching them.
• Acoustic metamaterials and phononic crystals
  3 studies · Engineered structures that block, bend or steer sound using arranged resonators and lattices.
• Biosonar-inspired sonar and robots
  2 studies · Engineers copy bat and dolphin sonar for sensors, signal processing and robots.
• Echolocation in bats, dolphins and toothed whales
  3 studies · Bats and toothed whales find prey by sending out sounds and listening to the echoes. Bat echolocation was discovered by Griffin and Galambos in 1941. We found no checkable paper on how far animal research informed the early, separately developed human sonar, so we make no claim about it.
• Electric rays, electric catfish and electrolocation
  4 studies · Besides electric eels, several fish make electricity. Electric rays and electric catfish stun prey with strong shocks, while weakly electric fish use faint electric fields to sense their surroundings in the dark.
• Human echolocation
  2 studies · Some blind people navigate by making mouth clicks and listening to echoes.
• Infrasound in animals
  1 study · Some animals communicate with very low-pitched sounds that travel long distances.
• Shark electroreception (ampullae of Lorenzini)
  2 studies · Sharks, skates and rays sense the faint electric fields of prey with jelly-filled pores called ampullae of Lorenzini, first described in 1678.
• Ultrasound (imaging, focused ultrasound, sonogenetics)
  4 studies · Sound above human hearing, used to see inside the body, treat tissue without cutting, and even switch on neurons.
• Vibration and resonance energy harvesting
  2 studies · Small resonating devices that turn everyday vibrations into electricity for sensors.
• Whale song
  4 studies · Humpback whales sing long, repeated songs.