Accumulation points of subsets of the real numbers
Content created by Louis Wasserman.
Created on 2025-11-15.
Last modified on 2025-11-15.
module real-numbers.accumulation-points-subsets-real-numbers where
Imports
open import foundation.propositions open import foundation.subtypes open import foundation.universe-levels open import lists.sequences open import metric-spaces.accumulation-points-subsets-located-metric-spaces open import real-numbers.dedekind-real-numbers open import real-numbers.located-metric-space-of-real-numbers open import real-numbers.subsets-real-numbers
Idea
An
accumulation point¶
of a subset S of the
real numbers is an
accumulation point
of S in the
located metric space of the real numbers.
Accumulation points of subsets of ℝ
module _ {l1 l2 : Level} (S : subset-ℝ l1 l2) where is-accumulation-point-prop-subset-ℝ : subset-ℝ (l1 ⊔ lsuc l2) l2 is-accumulation-point-prop-subset-ℝ = is-accumulation-point-prop-subset-Located-Metric-Space ( located-metric-space-ℝ l2) ( S) is-accumulation-point-subset-ℝ : ℝ l2 → UU (l1 ⊔ lsuc l2) is-accumulation-point-subset-ℝ x = type-Prop (is-accumulation-point-prop-subset-ℝ x) accumulation-point-subset-ℝ : UU (l1 ⊔ lsuc l2) accumulation-point-subset-ℝ = type-subtype is-accumulation-point-prop-subset-ℝ
Recent changes
- 2025-11-15. Louis Wasserman. Every point in a proper closed interval in the real numbers is an accumulation point (#1679).