Math 711 - Model Theory
This course will be a classical model theory course which will touch on
all the basic themes with a modern lens. In addition to
emphasizing standard results like completeness and compactness, the
framework will be broadened from the start to include the multi-sorted
setting which will enable a naturual discussion of quotient objects via
imaginaries. Abstract model theoretic theorems such as the Beth
definability theorem and Lindstrom's characterization of first order
logic will be included in a practical setting. Applications of the
Henkin construction as well as the abstract role of ultraproducts will
be emphasized. The course will end with a proof of Morley's
categoricity theorem in the style of Baldwin-Lachlan with some emphasis
on the geometric nature of modern treatments.
Lecture times: TW 11 - 12:30; see the Fields website for zoom details.
Recommended text: Model theory: an introduction, by David Marker
Office hours: by appointment
Course evaluation: There will be 5 assignments (roughly one every two
weeks) and a final project. The assignments will be worth 50% of
the grade and the take-home final/project will also be worth 50%.
I will try to keep a running list of topics covered approximately week
by week with pointers to material in Marker's book and other sources.
Week 1: Jan. 11; languages and structures, formulas, interpretations and
theories - Chapter 1, Marker
Week 2: Jan. 18; homomorphisms, embeddings, elementarity,
Downward-Lowenheim Skolem, ultraproducts - Chapter 2, Marker and lecture
notes
Week 3: Jan. 25; atomic and elementary diagrams, upward
Lowenheim-Skolem, the logic topology and types, quantifier elimination;
we are somewhere between chapters 2, 3 and 4 of Marker's book
Week 4: Feb. 1: Ehrenfeucht-Fraisse games and elementarity; Lindstrom's
theorem - lecture notes and a different presentation in chapter 2 of
Marker
Week 5: Feb. 8: Model theoretic forcing and the Henkin construction;
omitting types - lecture notes and again, a different presentation in
chapter 2 of Marker
Week 6: Feb. 22: countable saturated models, homogeneity, universality;
Ryll-Nardzweski; general saturation; Skolem functions - most of this is
in chapter 4 of Marker
Week 7: Mar. 1: imaginaries and interpretability, T^eq - lecture notes
Week 8: Mar. 8: partition theorems (Ramsey's theorem, Erdos-Rado),
indiscernibles - most of this is in Marker's book; see Morley's
presentation from his logic colloquium notes, 1967
Week 9: Mar. 15: applications with
indiscernibles, omega-stable theories - Marker's book and lecture notes
Week 10: Mar. 22: Vaughtian pairs, Morley rank - Marker's book and a
different presentation in the lecture notes
Week 11: Mar. 29: Morley's categoricity
theorem
Week 12 and 13: Apr. 6 - Apr. 14: Finishing
up and final project presentations