1.3k citations
- The Ohio State UniversityUS39 papers
- Stanford UniversityUS38 papers
- Kavli Institute for Particle Astrophysics and CosmologyUS37 papers
- Goddard Space Flight CenterUS35 papers
- SLAC National Accelerator LaboratoryUS35 papers
- University of Maryland, College ParkUS33 papers
- Centre National de la Recherche ScientifiqueFR31 papers
- University of California, Santa CruzUS31 papers
- University of TriesteIT31 papers
- Max Planck Institute for Extraterrestrial PhysicsDE29 papers
- Institute of Space SciencesES28 papers
- Institut National de Physique Nucléaire et de Physique des ParticulesFR28 papers
39 papers · 1 filter
Acyclic Comprehension is equal to Stratified Comprehension
Zuhair Al-Johar, M. Randall Holmes
A new criterion of comprehension is defined, initially termed by myself as "connected" and finally as "Acyclic" by Mr. Randall Holmes. Acyclic comprehension simply asserts that for…
New jump operators on equivalence relations
John D. Clemens, Samuel Coskey
We introduce a new family of jump operators on Borel equivalence relations; specifically, for each countable group we introduce the -jump. We study the elementary properties…
Conjugacy for homogeneous ordered graphs
Samuel Coskey, Paul Ellis
We show that for any countable homogeneous ordered graph , the conjugacy problem for automorphisms of is Borel complete. In fact we establish that each such satisfies a…
On the classification of automorphisms of trees
Kyle Beserra, Samuel Coskey
We identify the complexity of the classification problem for automorphisms of a given countable regularly branching tree up to conjugacy. We consider both the rooted and unrooted c…
The classification of countable models of set theory
John Clemens, Samuel Coskey, Samuel Dworetzky
We study the complexity of the classification problem for countable models of set theory (ZFC). We prove that the classification of arbitrary countable models of ZFC is Borel compl…
On the classification of vertex-transitive structures
John Clemens, Samuel Coskey, Stephanie Potter
We consider the classification problem for several classes of countable structures which are "vertex-transitive", meaning that the automorphism group acts transitively on the eleme…