Author Archives: Assaf Rinot

Ramsey theory over partitions I: Positive Ramsey relations from forcing axioms

Joint work with Menachem Kojman and Juris Steprāns. Abstract. In this series of papers, we advance Ramsey theory of colorings over partitions. In this part, a correspondence between anti-Ramsey properties of partitions and chain conditions of the natural forcing notions … Continue reading

Posted in Partition Relations, Publications | Tagged , , , , , , | 1 Comment

A guessing principle from a Souslin tree, with applications to topology

Joint work with Roy Shalev. Abstract. We introduce a new combinatorial principle which we call $\clubsuit_{AD}$. This principle asserts the existence of a certain multi-ladder system with guessing and almost-disjointness features, and is shown to be sufficient for carrying out … Continue reading

Posted in Publications, Souslin Hypothesis, Topology | Tagged , , , , , , | 2 Comments

MFO workshop in Set Theory, April 2020

The Set Theory workshop in Obwerwolfach was supposed to take place April 2020, but was transformed into a webinar, due to COVID-19. Here you will find the title, abstract, slides and video of my webinar talk. Talk Title: Transformations of … Continue reading

Posted in Invited Talks | Comments Off on MFO workshop in Set Theory, April 2020

Transformations of the transfinite plane

Joint work with Jing Zhang. Abstract. We study the existence of transformations of the transfinite plane that allow one to reduce Ramsey-theoretic statements concerning uncountable Abelian groups into classical partition relations for uncountable cardinals. To exemplify: we prove that for every … Continue reading

Posted in Partition Relations, Publications | Tagged , , , , , , , , | 1 Comment

Fake Reflection

Joint work with Gabriel Fernandes and Miguel Moreno. Abstract. We introduce a generalization of stationary set reflection which we call filter reflection, and show it is compatible with the axiom of constructibility as well as with strong forcing axioms. We … Continue reading

Posted in Generalized Descriptive Set Theory, Publications | Tagged , , , , , , , , | 1 Comment

A microscopic approach to Souslin-tree constructions. Part II

Joint work with Ari Meir Brodsky. Abstract. In Part I of this series, we presented the microscopic approach to Souslin-tree constructions, and argued that all known $\diamondsuit$-based constructions of Souslin trees with various additional properties may be rendered as applications of … Continue reading

Posted in Publications, Souslin Hypothesis | Tagged , , , , , , , , | 2 Comments

Sigma-Prikry forcing II: Iteration Scheme

Joint work with Alejandro Poveda and Dima Sinapova. Abstract. In Part I of this series, we introduced a class of notions of forcing which we call $\Sigma$-Prikry, and showed that many of the known Prikry-type notions of forcing that centers … Continue reading

Posted in Compactness, Publications, Singular Cardinals Combinatorics | Tagged , , , , | 1 Comment

Knaster and friends II: The C-sequence number

Joint work with Chris Lambie-Hanson. Abstract. Motivated by a characterization of weakly compact cardinals due to Todorcevic, we introduce a new cardinal characteristic, the C-sequence number, which can be seen as a measure of the compactness of a regular uncountable … Continue reading

Posted in Compactness, Publications, Singular Cardinals Combinatorics | Tagged , , , , , , , , , , , , , | 1 Comment

The 15th International Workshop on Set Theory in Luminy, September 2019

I gave an invited talk at the 15th International Workshop on Set Theory in Luminy in Marseille, September 2019. Talk Title: Chain conditions, unbounded colorings and the C-sequence spectrum. Abstract: The productivity of the $\kappa$-chain condition, where $\kappa$ is a regular, … Continue reading

Posted in Invited Talks | Tagged , , , , | Comments Off on The 15th International Workshop on Set Theory in Luminy, September 2019

Sigma-Prikry forcing I: The Axioms

Joint work with Alejandro Poveda and Dima Sinapova. Abstract. We introduce a class of notions of forcing which we call $\Sigma$-Prikry, and show that many of the known Prikry-type notions of forcing that centers around singular cardinals of countable cofinality … Continue reading

Posted in Compactness, Publications, Singular Cardinals Combinatorics | Tagged , , , , , | 1 Comment