activity
20202026
most citedOn the variety of Euclidean point sets

1 citations · 1 across the 14 of their papers we have counts for

collaborators

15 papers

math.GN2026

Proper classes of non-embeddable continua

Gerald Kuba

Our main result is a construction of a class H of pathwise connected, locally connected, compact Hausdorff spaces such that (i) if X,Y are distinct spaces in H then a continuous, i…

math.GN2026

Many coarse topologies on the real line

Gerald Kuba

Let c denote the cardinality of the continuum. Let L denote the family of all Hausdorff topologies on the real line coarser than the natural topology. We construct 2^c pairwise non…

math.GN2025

Counting continua

Gerald Kuba

For infinite cardinals let denote the class of all compact Hausdorff spaces of weight and size . So if or . If F is a class of…

math.GN2025

On real functions with graphs either connected or locally connected

Gerald Kuba

Let S denote the family of all subspaces of the plane that are graphs of functions from the real line R to itself. We prove that S has two subfamilies G,H of spaces such that the c…

math.FA2024

Connected Hamel bases in Hilbert spaces

Gerald Kuba

Our main goal is to track down an algebraic basis of Hilbert space which is a connected and locally connected subset of the unit sphere.

math.GN2024

On compact subsets of the plane

Gerald Kuba

We construct a family F of compact and pathwise connected subsets of the Euclidean plane such that (i) the cardinality of F is that of the continuum (and hence extremely large) and…

math.GR2024

Many non-embeddable infinite groups

Gerald Kuba

Let K be a set of infinite cardinals such that the cardinality of K is the first strong limit cardinal greater than uncountably many strong limit cardinals. We construct a family o…

math.GM2020

Transfinite dimensions

Gerald Kuba

Let H be a Hilbert space and let F be the family of all countable subsets of an orthonormal basis of H. We show that if F is infinite then F is equipollent with every linear basis…

math.NT2020

On the distribution of reducible polynomials

Gerald Kuba

Let Y_n(t) denote the set of all polynomials over the ring Z which are reducible over the field Q and of degree n>1 and of height not greater than t. We show that the true order of…

math.AC2020

Cantor sets and fields of reals

Gerald Kuba

Our main result is a construction of four families C_1,C_2,B_1,B_2 which are equipollent with the power set of the real line R and satisfy the following properties. (i) The members…

math.GN2020

Counting overweight spaces

Gerald Kuba

Let c=2^aleph0 denote the cardinality of the continuum and let a,b,k be infinite cardinal numbers with a<b\leq 2^a. We show that there exist precisely 2^b T0-spaces of size a and w…

math.GN2020

Scattered and paracompact order topologies

Gerald Kuba

We show that (in ZFC) every infinite set S can be equipped with 2^|S| complete metrics which generate mutually non-homeomorphic scattered order topologies on S. Furthermore, we sho…

math.GN2020★ 1 cited

On the variety of Euclidean point sets

Gerald Kuba

We construct a continuum of non-homeomorphic compact subspaces of the real line R without singleton components. Thus from the purely topological point of view the real line contain…

math.CA2020

Increasing singular functions with arbitrary positive derivatives at densely lying points

Gerald Kuba

Let A be an arbitrary countable set of reals, for example A=Q. Let g be an arbitrary mapping from A into the positive reals, for example g(a)=2^a. We show how a strictly increasing…

math.GN2020

On decompositions of the real line

Gerald Kuba

Let X_t be a totally disconnected subset of the real line R for each t in R. We construct a partition {Y_t | t in R} of R into nowhere dense Lebesgue null sets Y_t such that for ev…