Upper Adjoint

Some articles on adjoint, upper adjoint:

Completeness (order Theory) - Completeness in Terms of Adjunctions
... certain suprema or infima provides left or right adjoint parts of suitable Galois connections ... X has a least element if and only if the function j has a lower adjoint j* 1 → X ... Dually, the existence of an upper adjoint for j is equivalent to X having a greatest element ...

Famous quotes containing the word upper:

    You doubt we read the stars on high,
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    Ralph Waldo Emerson (1803–1882)