4 citations · 25 across the 21 of their papers we have counts for
26 papers
Hyperarithmetic directions can all be exceptional for Marstrand's projection theorem
Noam Greenberg, Daniel Turetsky
We show that there is a subset of the Euclidean plane, of Hausdorff dimension 1, such that for every line through the origin with hyperarithmetic direction, the…
Low computably enumerable sets have hyperhypersimple supersets
Peter Cholak, Rodney Downey, Noam Greenberg
A longstanding question is to characterize the lattice of supersets (modulo finite sets), , of a low computably enumerable (c.e.) set. The conjecture is that…
An Effective Classification of Borel Wadge Classes
Adam Day, Noam Greenberg, Matthew Harrison-Trainor +1
We give a new and effective classification of all Borel Wadge classes of subsets of Baire space. This relies on the true stage machinery originally developed by Montalbán. We use t…
Iterated Priority Arguments in Descriptive Set Theory
Adam Day, Noam Greenberg, Matthew Harrison-Trainor +1
We present the true stages machinery and illustrate its applications to descriptive set theory. We use this machinery to provide new proofs of the Hausdorff-Kuratowski and Wadge th…
Cousin's lemma in second-order arithmetic
Jordan Mitchell Barrett, Rodney G. Downey, Noam Greenberg
Cousin's lemma is a compactness principle that naturally arises when studying the gauge integral, a generalisation of the Lebesgue integral. We study the axiomatic strength of Cous…
Computing sets from all infinite subsets
Noam Greenberg, Matthew Harrison-Trainor, Ludovic Patey +1
A set is introreducible if it can be computed by every infinite subset of itself. Such a set can be thought of as coding information very robustly. We investigate introreducible se…