MAT 215A, Winter 2023


Instructor: Eugene Gorsky, egorskiy AT
Office hours: Thursdays 2-3pm on zoom.
Teaching Assistant: Shanon Rubin, srubin AT
Office hours: Discussion sections on Thursdays 10-10:50am at 2112, immediately followed by Office Hour 11am-12pm.
If you have a question and cannot come at office hours, write me an email to schedule an appointment.


The textbook for the course is "Algebraic Topology" by Allen Hatcher.

Code of Academic Conduct

The Code of Academic Conduct exists to support high standards of behavior and to ensure fair evaluation of student learning. Students who violate the Code of Academic Conduct are subject to disciplinary sanctions that include censure, probation, suspension, deferred separation or dismissal from the University of California. The code can be found at this link , or here . Cheating will be taken extremely seriously, and will be referred to Student Judicial Affairs.

In particular, it is OK to discuss homework problems with others, but you have to write the solutions in your own words . You cannot copy solutions from other students, books or the Internet.

For the midterms and the final, you are not allowed to discuss problems with anyone else or search the Internet. It follows exactly the same rules as the in class exam. If we observe that your solutions match someone else's or some Internet resource, your exam grade will be annuled.

Academic Participation Requirements

The campus requires students to verify that they have begun each course for which they are registered via the Academic Participation program. This program also encourages students to acknowledge their responsibilities regarding academic integrity and the Code of Academic Conduct, reinforcing our campus culture of honesty.

MyUCDavis will notify students online and through email on the first day of instruction to complete their Academic Participation verification no later than the quarter add deadline. Failing to verify academic participation by this deadline may result in a reduction of the financial aid award.

Please see more details by this link .

Midterm 1

Midterm 1 will be in class on Friday, January 27. The exam will cover the whole chapter 0: cell complexes, homotopy and homotopy equivalence, Cellular Approximation and Homotopy Extension theorems.

Practice problems: see problems 1-20 from prelim practice sheet .

Final grade and exams

There will be two midterms on Friday, January 27 and on Wednesday, February 22.
The Final will be on Thursday, March 23, 8:00 a.m.-10:00 a.m.
The final grade is based on your grades for the homework, midterms and the final:

Homework Midterm I Midterm II Final Exam
40% 20% 20% 20%


1. Cell complexes, operations on spaces. HW 1

2. Homotopy, homotopy equivalence. HW 2

3. Fundamental group. HW 3

4. Van Kampen's Theorem. HW 4

5. Covering spaces. HW 5

6. Higher homotopy groups. HW 6

7. Long exact sequence for higher homotopy groups.

Disability Services

Any student with a documented disability who needs to arrange reasonable accommodations must contact the Student Disability Center (SDC). Faculty are authorized to provide only the accommodations requested by the SDC. If you have any questions, please contact the SDC at (530)752-3184 or