Recent experimental develop menta in generation and detection of THz acoustical phonon. have led to studies of phonon emission, propagation and absorption in solidi. New resulta of this acoustical phonon spectroscopy concern phonon interaction. with collective excitations (phonons, photons, magnons), localized exoitations (resonant scattering of impurities, radiationleas transi. tions) and elec...

Perham (2010) describes the “irrelevant sound effect (ISE)” – or the presence of sound that is irrelevant to the task at hand. According to his research, sounds that exhibit “acute changing states” or acoustical variations impair outcomes when performing a memory or linear task, such as recalling a string of numbers. Sounds with little acoustical variation, or “steady state sounds” don’t impair...