Modern Meaning in The Physical Sciences
In the 17th century the word spectrum was introduced into optics, referring to the range of colors observed when white light was dispersed through a prism. Soon the term referred to a plot of light intensity or power as a function of frequency or wavelength, also known as a spectral density.
The term spectrum was expanded to apply to other waves, such as sound waves that could also be measured as a function of frequency. The term now applies to any signal that can be measured or decomposed along a continuous variable such as energy in electron spectroscopy or mass to charge ratio in mass spectrometry. Spectrum is also used to refer to a graphical representation of the as a function of the dependent variable.
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Famous quotes containing the words modern, meaning, physical and/or sciences:
“However far modern science and technics have fallen short of their inherent possibilities, they have taught mankind at least one lesson: Nothing is impossible.”
—Lewis Mumford (18951990)
“In our definitions, we grope after the spiritual by describing it as invisible. The true meaning of spiritual is real; that law which executes itself, which works without means, and which cannot be conceived as not existing.”
—Ralph Waldo Emerson (18031882)
“I have no purpose to introduce political and social equality between the white and black races. There is a physical difference between the two, which, in my judgement, will probably for ever forbid their living together upon the footing of perfect equality; and inasmuch as it becomes a necessity that there must be a difference, I ... am in favour of the race to which I belong having the superior position.”
—Abraham Lincoln (18091865)
“Criticism is a study by which men grow important and formidable at very small expense. The power of invention has been conferred by nature upon few, and the labour of learning those sciences which may, by mere labour, be obtained, is too great to be willingly endured; but every man can exert some judgment as he has upon the works of others; and he whom nature has made weak, and idleness keeps ignorant, may yet support his vanity by the name of critic.”
—Samuel Johnson (17091784)