ThmDex – An index of mathematical definitions, results, and conjectures.
▼ Set of symbols
▼ Alphabet
▼ Deduction system
▼ Theory
▼ Zermelo-Fraenkel set theory
▼ Set
▼ Binary cartesian set product
▼ Binary relation
▼ Binary endorelation
▼ Preordering relation
▼ Partial ordering relation
▼ Partially ordered set
▼ Minimal element
▼ Minimum element
▼ Set lower bound
▼ Set of lower bounds
Definition D301
Infimum element
Formulation 0
Let $P = (X, {\preceq})$ be a D1103: Partially ordered set.
Let $\mathsf{LB} = \mathsf{LB}_P(E)$ be the D553: Set of lower bounds of $E \subseteq X$ with respect to $P$.
A D2218: Set element $x_0 \in X$ is an infimum of $E$ with respect to $P$ if and only if
(1) $x_0 \in \mathsf{LB}$
(2) $\forall \, x \in \mathsf{LB} : x \preceq x_0$
Formulation 1
Let $P = (X, {\preceq})$ be a D1103: Partially ordered set.
Let $\mathsf{LB} = \mathsf{LB}_P(E)$ be the D553: Set of lower bounds of $E \subseteq X$ with respect to $P$.
A D2218: Set element $x_0 \in X$ is an infimum of $E$ with respect to $P$ if and only if
(1) $x_0 \in \mathsf{LB}$
(2) $\forall \, x \in \mathsf{LB} : (x, x_0) \in {\preceq}$
Also known as
Greatest lower bound