21 lines
4.1 KiB
TeX
21 lines
4.1 KiB
TeX
\subsection{Galileo}
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If there is some question about Bacon's discussion of the wet-finger-around-the-wine-glass-rim phenomenon because he doesn't mention the sound, Galileo's discussion of the same phenomenon leaves no doubt.
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Galileo's father Vincenzo Galileo (c.1525\EnDash{}1591) was a preeminent musician and music theorist of his day. Since antiquity, the theory of music had consisted of a mathematical discussion of harmony (based on Pythagoras' observations), in other words what are the mathematical ratios of the lengths of strings producing consonances, and how does one divide the octave? It had always been thought that not only was the ratio of lengths of two strings sounding an octave 2:1, but that so also was the ratio of the tensions of strings of equal lengths tuned an octave apart. Vincenzo showed that this is not the case: the ratio of tensions is 4:1. He found that ratio by hanging weights from strings. Here was an experiment (conducted in 1588, when his son Galileo was living at home and giving private lessons in mathematics) that produced numbers and bore directly on the age-old theoretical discussions. The example was certainly not lost on his son.
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The better part of Galileo's career was spent observing the heavens through his telescope, founding modern astronomy and proving the Copernican heliocentric model of the solar system in the process.
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Galileo's lenses must have been expertly ground from glass that was both thick and clear, and surely made in Murano. Galileo continued to improve on the telescope until he finally attained magnifications of up to thirty times; this was actually the maximum that could be achieved with his basically simple telescope. It was with lenses like these that he made his revolutionary discoveries in astronomy. \footnote{Polak, 87-88}
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We also know that Galileo himself was an accomplished amateur lute player and composer, trained by his celebrated musical father no doubt. Galileo even used his musical training to subdivide time in his physics experiments!\footnote{Drake (1975)}
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Galileo's wrote his last book, \Title{Two New Sciences} (1638)\footnote{Galileo}, while under house arrest by the Vatican. At the time he was suffering from very poor health, including the loss of sight in one of his eyes. (Medical attention was finally begrudgingly permitted after Galileo was completely blind, which occurred shortly after completing his book). He was also grieving the loss of his beloved daughter Maria Celeste (who died at age 33), and under strict orders not to write anything about astronomy. So instead he wrote about the strength and resistance of materials, and the physics of moving objects\EmDash{}his 'two new sciences'\EmDash{}arguably founding modern physics in the process. It encompassed 30 years of highly original experimentation, discussing aspects of the fracture of solid bodies, cohesion, leverage, the speed of light, sound, pendulums, falling bodies, projectiles, uniform motion, accelerated motion, the strength of wires, rods and beams under different loadings and placements-and the musical wineglass.
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Galileo was also forbidden to publish anything, ``not even the Lord's Prayer''\footnote{Sharratt, 184}, but Galileo managed to publish his book anyway by heroic intrigues which kept both him and his publisher out of trouble with the Inquisition.\footnote{Sharratt, 185}
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Galileo knew this was his last book, and he wrote it under terribly difficult circumstances, yet he digresses for several pages to consider the wet finger around the wine glass phenomenon:
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\begin{quote}
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If one bows the base string on a viola rather smartly and brings near it a goblet of fine, thin glass having the same tone [tuono] as that of the string, this goblet will vibrate and audibly resound [the first mention of 'sympathetic resonance'?]. That the undulations of the medium are widely dispersed about the sounding body is evinced by the fact that a glass of water may be made to emit a tone merely by the friction of the finger-tip upon the rim of the glass; for in this water is produced a series of regular waves.\ldots[Galileo, 99-101]
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\end{quote}
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