# Indiscernible extraction and Morley sequences

This is the title of a talk given at the 2014 Logic Colloquium (Vienna University of Technology) on Jul. 19, 2014. The talk presents the corresponding paper. Here are the slides.

## Abstract

We present a new proof of the existence of Morley sequences in simple theories. We avoid using the Erdős-Rado theorem and instead use Ramsey's theorem. The proof shows that the basic theory of forking in simple theories can be developed inside H ((2^{2|T|})^{+}) without using the axiom of replacement, answering a question of Grossberg, Iovino and Lessmann, as well as a question of Baldwin.

## References

- Sebastien Vasey,
*Indiscernible extraction and Morley sequences*, Accepted (June 9, 2014), Notre Dame Journal of Formal Logic. Preprint: pdf arXiv.
- Rami Grossberg, José Iovino, Olivier Lessmann.
*A primer of simple theories*, Archive for Mathematical Logic 41 (2002), no. 6, 541-580.
- Hans Adler.
*Thorn-forking as local forking*, Journal of Mathematical Logic 9 (2009), no. 1, 21--38.