Math 662: Seminar in Algebra
Homological Algebra
Spring 2025

Instructor: Sarah Witherspoon
Email: sjw AT tamu.edu
Office and hours: Blocker 513B, TR 5:10 - 6 pm, or by appointment

Course web address: https://people.tamu.edu/~sjw/math662_2025.html

Class meetings: MWF 1:50-2:40, in Blocker 148

Optional Texts: An Introduction to Homological Algebra, C. A. Weibel, Cambridge University Press, 1994.
A Course in Homological Algebra, P. J. Hilton and U. Stammbach, Springer-Verlag, 1971.
Basic Homological Algebra, M. S. Osborne, Springer, 2000.
An Introduction to Homological Algebra, J. J. Rotman, Springer, 2009.
Appendix to Hochschild Cohomology for Algebras, S. J. Witherspoon, GSM 204, American Mathematical Society, 2019, available at https://www.math.tamu.edu/~sjw/pub/gsm204.pdf.



Course requirements and grades
Course prerequisite: Math 654 or equivalent.
Course grades will be based on homework, to be assigned approximately every 3 weeks, and class participation. Grades are assigned as follows based on homework: A (80-100%), B(60-79%), C(40-59%), D(20-39%), F(0-19%).

Course description
3.0 credits. Selected topics in algebra. May be repeated for credit.

This course will cover the basics of homological algebra, in preparation for more advanced study and research in fields in which homological techniques are used. Topics will be taken from the optional textbooks listed above and from other sources. This will include chain complexes, resolutions, Ext, Tor, long exact sequences, homological dimension, Hilbert Syzygy Theorem, derived functors, derived categories, Künneth Theorem, spectral sequences, and further topics as time permits.



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