Spectrum - Modern Meaning in The Physical Sciences

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:

    I lately met with an old volume from a London bookshop, containing the Greek Minor Poets, and it was a pleasure to read once more only the words Orpheus, Linus, Musæus,—those faint poetic sounds and echoes of a name, dying away on the ears of us modern men; and those hardly more substantial sounds, Mimnermus, Ibycus, Alcæus, Stesichorus, Menander. They lived not in vain. We can converse with these bodiless fames without reserve or personality.
    Henry David Thoreau (1817–1862)

    Man is eminently a storyteller. His search for a purpose, a cause, an ideal, a mission and the like is largely a search for a plot and a pattern in the development of his life story—a story that is basically without meaning or pattern.
    Eric Hoffer (1902–1983)

    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)

    The well-educated young woman of 1950 will blend art and sciences in a way we do not dream of; the science will steady the art and the art will give charm to the science. This young woman will marry—yes, indeed, but she will take her pick of men, who will by that time have begun to realize what sort of men it behooves them to be.
    Ellen Henrietta Swallow Richards (1842–1911)