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 physical sciences, modern, meaning, physical and/or sciences:
“I hope I may claim in the present work to have made it probable that the laws of arithmetic are analytic judgments and consequently a priori. Arithmetic thus becomes simply a development of logic, and every proposition of arithmetic a law of logic, albeit a derivative one. To apply arithmetic in the physical sciences is to bring logic to bear on observed facts; calculation becomes deduction.”
—Gottlob Frege (18481925)
“Though collecting quotations could be considered as merely an ironic mimetismvictimless collecting, as it were ... in a world that is well on its way to becoming one vast quarry, the collector becomes someone engaged in a pious work of salvage. The course of modern history having already sapped the traditions and shattered the living wholes in which precious objects once found their place, the collector may now in good conscience go about excavating the choicer, more emblematic fragments.”
—Susan Sontag (b. 1933)
“Tis good to give a stranger a meal or a nights lodging. Tis better to be hospitable to his good meaning and thought, and give courage to a companion. We must be as courteous to a man as we are to a picture, which we are willing to give the advantage of a good light.”
—Ralph Waldo Emerson (18031882)
“Whenever reality reinforces a childs fantasied dangers, the child will have more difficulty in overcoming them...So, while parents may not regard a spanking as a physical attack or an assault on a childs body, the child may regard it as such, and experience it as a confirmation of his fears that grown-ups under certain circumstances can really hurt you.”
—Selma H. Fraiberg (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 marryyes, 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 (18421911)