2026 (Current Year) Faculty Courses School of Computing Department of Mathematical and Computing Science Graduate major in Mathematical and Computing Science
Discrete, Algebraic and Geometric Structures
- Academic unit or major
- Graduate major in Mathematical and Computing Science
- Instructor(s)
- Sakie Suzuki / Shinya Nishibata / Masaaki Umehara / Zin Arai
- Class Format
- Lecture
- Media-enhanced courses
- -
- Day of week/Period
(Classrooms) - unknown
- Class
- -
- Course Code
- MCS.T408
- Number of credits
- 200
- Course offered
- 2026
- Offered quarter
- 3Q
- Syllabus updated
- Aug 28, 2026
- Language
- English
Syllabus
Course overview and goals
This course introduces algebraic and geometric structures arising in knot theory and quantum topology from the viewpoint of category theory. Topics include monoidal categories, braid and tangle categories, dualities, pivotal categories, and ribbon categories. We also study Hopf algebras and their representation categories to understand how these categorical structures arise from algebra. Through concrete examples and graphical calculus, students will explore the common mathematical structures underlying discrete, algebraic, and geometric objects.
Course description and aims
By taking this course, students will understand the basic concepts of categories, functors, natural transformations, monoidal categories, braided categories, dualities, pivotal categories, and ribbon categories, and will be able to work with these structures in concrete examples. Students will also learn to use graphical calculus and understand monoidal structures, dualities, and braidings arising in representation categories of Hopf algebras.
Keywords
category theory, monoidal category, braids and tangles, pivotal and ribbon categories, Hopf algebra, quantum topology
Competencies
- Specialist skills
- Intercultural skills
- Communication skills
- Critical thinking skills
- Practical and/or problem-solving skills
Class flow
In addition to lectures, the course includes pair-work exercises. Students will discuss basic definitions and concrete examples with their partners and present solutions to selected exercises on the board.
Course schedule/Objectives
| Course schedule | Objectives | |
|---|---|---|
| Class 1 | Categories and functors |
Understand the contents covered by the lecture. |
| Class 2 | Natural transformations |
Understand the contents covered by the lecture. |
| Class 3 | Monoidal categories |
Understand the contents covered by the lecture. |
| Class 4 | Monoidal functors |
Understand the contents covered by the lecture. |
| Class 5 | Category of braids |
Understand the contents covered by the lecture. |
| Class 6 | Braided categories |
Understand the contents covered by the lecture. |
| Class 7 | Category of tangles and its dualities |
Understand the contents covered by the lecture. |
| Class 8 | Category of framed tangles and its twists |
Understand the contents covered by the lecture. |
| Class 9 | Dualities, rigid monoidal categories, and dual functors |
Understand the contents covered by the lecture. |
| Class 10 | Pivotal categories and graphical calculus |
Understand the contents covered by the lecture. |
| Class 11 | Ribbon categories |
Understand the contents covered by the lecture. |
| Class 12 | Algebras, bialgebras, and their modules |
Understand the contents covered by the lecture. |
| Class 13 | Ribbon Hopf algebras and their modules |
Understand the contents covered by the lecture. |
| Class 14 | Reshetikhin-Turaev functor |
Understand the contents covered by the lecture. |
Study advice (preparation and review)
In order to enhance learning outcomes, students should refer to the relevant sections of textbooks or distributed materials, and spend approximately 100 minutes each on preparation and review (including assignments) related to the content of each class.
Textbook(s)
Not specified in particular.
Reference books, course materials, etc.
References and some handouts will be provided in the lectures.
Evaluation methods and criteria
Grades will be based on in-class pair-work exercises, board presentations, and the final examination. Pair work will be evaluated based on understanding of the course material and participation in discussion, board presentations on understanding of the problems and clarity of explanation, and the final examination on overall understanding of the course material.
Related courses
- MCS.T231 : Algebra
- MCS.T201 : Set and Topology I
Prerequisites
None.