On Sums of "Small" Cantor Sets
Abstract
We provide several results showing that sums of ``small'' Cantor sets can turn into an interval or a finite union of intervals. Specifically, we show that 1) There exists a Cantor set C⊂ [0,1] of zero logarithmic capacity such that C+C=[0,2]. 2) For any n≥ 2 there exists a Cantor set C⊂ [0,1] of zero logarithmic capacity such that a Minkowski sum of n copies of C is an interval [0,n], while a sum of any smaller number of copies of C is still a Cantor set. 3) For any n≥ 2 there exists a collection of Cantor sets C1, C2, …, Cn⊂ [0,1] of zero lower box-counting dimension such that a Minkowski sum of any n−1 sets from this collection is a Cantor set of zero lower box-counting dimension, while the sum of all n sets is an interval [0,n]. 4) There is an uncountable family of Cantor sets of zero lower box-counting dimension such that the sum of any two different sets from this family is a finite union of intervals. 5) For each of the properties above, there are examples of Cantor sets with the same property having zero Hausdorff h-measure for an arbitrary given gauge function h.
Related
BibTeX
@misc{gorodetski2026sums,
title = {{On Sums of "Small" Cantor Sets}},
author = {Anton Gorodetski and Alexandro Luna and William Wood},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.17005},
eprint = {2610.17005},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.17005},
}
RIS
TY - UNPB
TI - On Sums of "Small" Cantor Sets
AU - Anton Gorodetski
AU - Alexandro Luna
AU - William Wood
PY - 2026
DA - 2026/10/12
PB - arXiv
DO - 10.48550/arxiv.2610.17005
UR - https://arxiv.org/abs/2610.17005
AB - We provide several results showing that sums of ``small'' Cantor sets can turn into an interval or a finite union of intervals. Specifically, we show that 1) There exists a Cantor set C⊂ [0,1] of zero logarithmic capacity such that C+C=[0,2]. 2) For any n≥ 2 there exists a Cantor set C⊂ [0,1] of zero logarithmic capacity such that a Minkowski sum of n copies of C is an interval [0,n], while a sum of any smaller number of copies of C is still a Cantor set. 3) For any n≥ 2 there exists a collection of Cantor sets C_1, C_2, …, C_n⊂ [0,1] of zero lower box-counting dimension such that a Minkowski sum of any n−1 sets from this collection is a Cantor set of zero lower box-counting dimension, while the sum of all n sets is an interval [0,n]. 4) There is an uncountable family of Cantor sets of zero lower box-counting dimension such that the sum of any two different sets from this family is a finite union of intervals. 5) For each of the properties above, there are examples of Cantor sets with the same property having zero Hausdorff h-measure for an arbitrary given gauge function h.
ER -