Selection Rule

In physics and chemistry a selection rule, or transition rule, formally constrains the possible transitions of a system from one state to another. Selection rules have been derived for electronic, vibrational, and rotational transitions. The selection rules may differ according to the technique used to observe the transition.

Read more about Selection Rule:  Overview

Famous quotes containing the words selection and/or rule:

    When you consider the radiance, that it does not withhold
    itself but pours its abundance without selection into every
    nook and cranny
    Archie Randolph Ammons (b. 1926)

    The art of being a slave is to rule one’s master.
    Diogenes of Sinope (c. 410–c. 320 B.C.)