imaginary quadratic fieldImaginaryQuadraticField2008-04-05 03:49:482008-10-27 13:21:54Definitionnumber fieldreal quadratic field% this is the default PlanetMath preamble. as your knowledge
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A quadratic number field \,$\mathbb{Q}(\sqrt{d})$,\, where $d$ is a negative squarefree integer, is called a {\em imaginary quadratic field}.
The name may be thought to describe the fact that such a quadratic field \PMlinkescapetext{contains} ``imaginary numbers'' (in the sense `non-real complex numbers').
Other quadratic fields are {\em real quadratic fields}.