3 papers
math.GN2026
Topology, forcing, and graph colourings
Noam Greenberg, Dominique Lecomte, Dan Turetsky +1
We introduce a family of forcing notions that are helpful in showing that certain graphs do not have countable colourings of (additive) Borel class alpha. We construct graphs that…
math.LO2026
Forcing and classes of -dominating functions
Noam Greenberg, Gian Marco Osso
We study the question, what computational power is sufficient to perform constructions using either Laver or Hechler forcing. As a result, we obtain a separation between three rela…
math.LO2021
Many forcing axioms for all regular uncountable cardinals
Noam Greenberg, Saharon Shelah
A central theme in set theory is to find universes with extreme, well-understood behaviour. The case we are interested in is assuming GCH and has a strong forcing axiom of higher o…