Research tool
The ability to control laser wavelength and pulse duration precisely has proved invaluable for fundamental research in physics and other sciences. Lasers have been particularly important in spectroscopy, the study of the light absorbed and emitted when atoms and molecules make transitions between energy levels, which can reveal the inner workings of atoms. Lasers can concentrate much more power into a narrow range of wavelengths than other light sources, which makes them invaluable in analyzing fine spectroscopic details. For example, simultaneously illuminating samples with laser beams coming from opposite directions can cancel the effects of the random motions of atoms or molecules in a gas. This technique has greatly improved the precision of the measurement. These techniques have led to the creation of a new state of matter, called a Bose-Einstein condensate. Just for Fun v 25.Now try this quiz:
GRAMMAR FOCUS REVISION OF THE SUBJUNCTIVE MOOD
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