Slender Trees and the Approximation Property

2024/01/24 by Jakob, Hannes
#03E05 (Primary) #03E35 #03E55 #FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2401.13446

Abstract

We obtain a relatively simple criterion for when a forcing has the < δ-approximation property, generalizing a result of Unger. Afterwards we apply this criterion to construct variants of Mitchell Forcing in order to answer questions posed by Mohammadpour.

Related

• Mitchell-style forcing, with small working parts and collections of\n models as side conditions, and gap-one simplified morasses
• Specializing Trees with Small Approximations I
• Specializing Aronszajn trees by countable approximations
• Proper forcing remastered
• Classical Namba forcing can have the weak countable approximation property