A real embedding of a number field 
is a field embedding 
whose image
is contained in R. Equivalently, 
is real for every
. The number of real embeddings of 
is the first component of the number
field signature.
Real Embedding
See also
Complex Number, Field Embedding, Imaginary Embedding, Number Field Signature, Real Number, Totally Imaginary Field, Totally Real FieldExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Real Embedding." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RealEmbedding.html