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.
Read more about this topic: Spectrum
Famous quotes containing the words modern, meaning, physical and/or sciences:
“How little do the most wonderful inventions of modern times detain us. They insult nature. Every machine, or particular application, seems a slight outrage against universal laws.”
—Henry David Thoreau (1817–1862)
“The sick are parasites on society. In a certain state it is indecent to go on living. To continue vegetating in cowardly dependence on physicians and machinations once the meaning of life, the right to life, has been lost ought to occasion a deep contempt within society.”
—Friedrich Nietzsche (1844–1900)
“The term preschooler signals another change in our expectations of children. While toddler refers to physical development, preschooler refers to a social and intellectual activity: going to school. That shift in emphasis is tremendously important, for it is at this age that we think of children as social creatures who can begin to solve problems.”
—Lawrence Kutner (20th century)
“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 (1709–1784)