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The History of Acoustics
Acoustics, one of the oldest branches of physics, originated with Pythagoras's studies of music over 2,500 years ago. Scientific milestones abound in this field:

  • Galileo Galilei (1564-1642) discovered the general principles of sympathetic vibrations, or resonance, and the correspondence between the frequency of vibrations and the length of a pendulum.

  • Leonhard Euler and Daniel Bernoulli's studies of vibrating cords in the 18th century eventually led to the development of Fourier analysis, one of the most important tools of mathematics and mathematical physics.

  • Sir Isaac Newton and Gottfried Wilhelm Leibniz independently developed the theory of calculus, which in turn allowed the derivation of the general wave equation by the French mathematician and scientist Jean Le Rond d'Alembert in the 1740s.

  • Hermann von Helmholtz's On the Sensations of Tone As a Physiological Basis for the Theory of Music (1863) made substantial contributions to understanding the mechanisms of hearing and to the psychophysics of sound and music.

  • John William Strutt's The Theory of Sound (1877/78), a monument of acoustical literature, was the first treatise to examine questions of vibrations, the resonance of elastic solids and gases, and acoustical propagation in material media.

  • Jean Baptiste-Joseph Fourier, a 19th-century French mathematician, established his theory about the analysis of a complex periodic wave into its spectral components.

  • German physicist Georg Simon Ohm hypothesized that the human ear is sensitive to these spectral components. His Law of Hearing stated that the ear is sensitive to the amplitudes, but not the phases, of the harmonics of a complex tone.

  • 20th-century American physicist Wallace Sabine initiated the science of modern architectural acoustics by finding ways to correct the acoustics of noisy rooms.

  • Hungarian-born American physicist Georg von Békésy validated Helmholtz's theory of hearing with his Experiments in Hearing (1960), the classic of the modern theory of the ear.

Current branches of acoustical study consider the auditory aspects of telephony, radio and sound reproduction (communications acoustics); the behavior of sound waves in interior environments (architectural acoustics) and exterior environments (environmental acoustics); and the nature of speech and hearing (physiological acoustics).



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