activity
20162024
most citedThe topological dimension of radial Julia sets

7 citations · 38 across the 19 of their papers we have counts for

collaborators

21 papers

math.GN2024

Endpoints of smooth plane dendroids

David S. Lipham

Let be a smooth dendroid in the plane . We show that each endpoint of is arcwise accessible from , and that the space of endpoints $E(X…

math.GN2023★ 1 cited

A dichotomy for spaces near dimension zero

David S. Lipham

We prove that the classes of weakly -dimensional and almost -dimensional spaces are disjoint. The result has applications to hereditarily locally connected spaces, $\mathbb R…

math.GN2022

Meager composants of tree-like continua

David S. Lipham

A subset of a continuum is called a \textit{meager composant} if is maximal with respect to the property that every two of its points are contained in a nowhere dense s…

math.GN2022

Totally disconnected subsets of chainable continua

David S. Lipham

We show that the endpoint set of a Suslinian chainable continuum must be zero-dimensional at some point. In particular, it cannot be homeomorphic to complete Erdős space. This answ…

math.GN2021

The -product of complete Erdős space

David S. Lipham

We show that the -product of complete Erdős space is homeomorphic to the rational product , answering a ques…

math.GN2020★ 1 cited

Exponential iteration and Borel sets

David S. Lipham

We determine the exact Borel class of the points whose iterates under tend to infinity. We also prove that the sets of non-escaping Julia points for many of these funct…

math.GN2020★ 1 cited

A characterization of Erdős space factors

David S. Lipham

We prove that an almost zero-dimensional space is an Erdős space factor if and only if has a Sierpiński stratification of C-sets. We apply this characterization to spaces w…

math.DS2020★ 2 cited

Distinguishing endpoint sets from Erdős space

David S. Lipham

We prove that the set of all endpoints of the Julia set of which escape to infinity under iteration of is not homeomorphic to the rational Hilbert space $\math…

math.DS2020★ 1 cited

Erdős space in Julia sets

David S. Lipham

We prove that the rational Hilbert space , known as Erdős space, surfaces in complex dynamics via iteration of .

math.GN2020★ 6 cited

On cohesive almost zero-dimensional spaces

Jan J. Dijkstra, David S. Lipham

We investigate C-sets in almost zero-dimensional spaces, showing that closed C-sets are C-sets. As corollaries, we prove that every rim--compact almost zero-dimensional space…

math.DS2020★ 7 cited

The topological dimension of radial Julia sets

David S. Lipham

We prove that the meandering set for is homeomorphic to the space of irrational numbers whenever belongs to the Fatou set of . This extends recent results b…

math.GN2019★ 1 cited

Approximations by disjoint continua and a positive entropy conjecture

David Sumner Lipham

E.D. Tymchatyn constructed a hereditarily locally connected continuum which can be approximated by a sequence of mutually disjoint arcs. We show the example re-opens a conjecture o…

math.GN2019

Compactification of cut-point spaces

David S. Lipham

We show that if is a separable locally compact Hausdorff connected space with fewer than non-cut points, then embeds into a dendrite …

math.DS2019★ 2 cited

A note on the topology of escaping endpoints

David Sumner Lipham

We study topological properties of the escaping endpoints and fast escaping endpoints of the Julia set of complex exponential when . We show neither…

math.GN2019★ 1 cited

Dispersion points and rational curves

David Sumner Lipham

We construct two connected plane sets which can be embedded into rational curves. The first is a biconnected set with a dispersion point. It answers a question of Joachim Grispolak…

math.GN2018★ 3 cited

Singularities of meager composants and filament composants

David Sumner Lipham

Suppose is a continuum, , and is the union of all nowhere dense subcontinua of containing . Suppose further that there exists such that every connec…

math.GN2018★ 2 cited

Embedding irreducible connected sets

David Sumner Lipham

We show that every connected set which is irreducible between two points and embeds into the Hilbert cube in a way that is irreducible between and …

math.GN2017★ 1 cited

One-to-one composant mappings of and

David Lipham

Knaster continua and solenoids are well-known examples of indecomposable continua whose composants (maximal arcwise-connected subsets) are one-to-one images of lines. We show that…

math.GN2017★ 4 cited

On indecomposability of

David Sumner Lipham

The following is an open problem in topology: Determine whether the Stone-Čech compactification of a widely-connected space is necessarily an indecomposable continuum. Herein we de…

math.GN2016

Large widely-connected spaces

David Lipham

We show that there are widely-connected spaces of arbitrarily large cardinality, answering a question by David Bellamy.

math.GN2016★ 5 cited

Widely-connected sets in the bucket-handle continuum

David Sumner Lipham

A connected topological space is said to be widely-connected if each of its non-degenerate connected subsets is dense in the entire space. The object of this paper is the construct…