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Source labels openMillennium Problems · General topology

Poincare: Smooth Dimension Four

The four dimensional case of the smooth version of the conjecture is still open. See [Wang2017].

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openMillennium Problems · General topology

Poincare: Smooth Other Cases

It is conjectured that the only values of n>4n > 4 for which the smooth version of the conjecture holds are n=5,6,12,56,61n = 5, 6, 12, 56, 61. See Conjecture 1.17 in [Wang2017].

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjecture about cardinality of Lindelöf spaces

Is there a Lindelöf space with singletons as Gδ sets with cardinality greater than the continuum?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openMathOverflow · Real functions

Mathoverflow 235893

Assume for n>1n>1, f:RnRnf:\mathbb{R}^n\to\mathbb{R}^n is a bijection, where Rn\mathbb{R}^n is equipped with the standard topology. Does the connectedness of (the induced power set map) ff imply that of f1f^{-1}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures around homogeneous topological spaces

Problem 13 in [Ar2013]: Is it true that every infinite homogeneous compact hausdorff space contains a non-trivial convergent sequence?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures around homogeneous topological spaces

Problem 14 in [Ar2013]: Is it possible to represent an arbitrary compact hausdorff space as an image of a homogeneous compact space under a continuous mapping?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures around homogeneous topological spaces

Problem 15 in [Ar2013]: Is every homogeneous ω-monolithic compact hausdorff space first countable?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures around homogeneous topological spaces

Problem 16 in [Ar2013]: Is the cardinality of every homogeneous ω-monolithic compact hausdorff space not greater than 𝔠?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures around homogeneous topological spaces

Problem 17 in [Ar2013]: Is it true that every nonempty ω-monolithic compact hausdorff space contains a point with a first countable neighborhood basis?

Note: Nonempty X is required since the conclusion asserts the existence of a point.

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures about Weakly First Countable spaces

Problem 2 in [Ar2013]: Give an example in ZFC of a weakly first- countable compact Hausdorff space X such that 𝔠<X𝔠 < |X|.

Note: [Ar2013] uses a blanket convention that all spaces are Tychonoff and "compact" means compact Hausdorff.

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · General topology

Conjectures about Weakly First Countable spaces

Problem 3 in [Ar2013]: Give an example in ZFC of a weakly first- countable compact Hausdorff space which is not first countable.

Note: [Ar2013] uses a blanket convention that all spaces are Tychonoff and "compact" means compact Hausdorff.

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openWikipedia · General topology

The Bing-Borsuk Conjecture

The Bing-Borsuk Conjecture: every nn-dimensional homogeneous absolute neighborhood retract is a topological nn-manifold. A topological space XX is an nn-dimensional manifold when T2Space X ∧ Nonempty (ChartedSpace (Fin n → ℝ) X). The hypothesis [MetrizableSpace X] implies T2Space X so this does not appear in the conclusion.

Source checked Jul 26, 20261 pinned Lean statementInspect problem