**Title: **An Introduction to Causal Set Theory

**Speaker: **Dionigi M.T. Benincasa (DIAS)

**Abstract: **Causal set theory is a sum-over-histories approach to quantum gravity, where the histories are discrete spacetimes (called causal sets) defined as locally finite partial orders. Causal sets were proposed independently by ’t Hooft, Myrheim, Finklestein and Sorkin in the 70s and 80s, and have been championed by R. Sorkin ever since.

In this talk I will give a brief introduction to causal set theory, building towards some of the developments of the last decade. These include a definition of the causal set scalar curvature, and therefore of a causal set action analogous to the Einstein-Hilbert action of GR, which can be used to define causal set dynamics; as well as a formulation of quantum field theory on causal sets. If time permits I will discuss some recent (puzzling) results concerning the entanglement entropy of a free scalar field on a causal set.

**Time:** Tuesday 13th February 2018, 2.30pm.

**Place: **Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.