ThmDex – An index of mathematical definitions, results, and conjectures.
Set of symbols
Alphabet
Deduction system
Theory
Zermelo-Fraenkel set theory
Set
Subset
Power set
Hyperpower set sequence
Hyperpower set
Hypersubset
Subset algebra
Boolean algebra
Sigma-algebra
Discrete sigma-algebra
Discrete measurable space
Point-mass measure
Counting measure
Definition D1703
Point measure
Formulation 0
Let $M = (X, \mathcal{F})$ be a D1108: Measurable space such that
(i) \begin{equation} X \neq \emptyset \end{equation}
(ii) $x \in X$ is a D2218: Set element in $X$
The point measure on $M$ with respect to $x$ is the D4361: Unsigned basic function \begin{equation} \mathcal{F} \to [0, \infty], \quad E \mapsto \left| E \cap \{ x \} \right| \end{equation}