MUSA

Problem of the Week

A 102 x 102 "chessboard" is displayed on a computer screen, with its squares colored in the standard alternating black-and-white pattern. One can select with a mouse any rectangle with sides on the lines of the chessboard and click the mouse button: as a result, the colors in the selected rectangle switch (black becomes white, white becomes black). Determine, with proof, the minimum number of mouse clicks required to transform the entire chessboard into a single uniform color.

Submit at this google form.

You can check out past problems in the archive! And if you have a problem you'd like to suggest for problem of the week, fill out this google form.

Upcoming Math Monday: Automated Mesh Generation using Graph Neural Networks and Reinforcement Learning

Per-Olof Persson
January 26

Abstract: Mesh generation, or the partitioning of a geometric domain into simple elements like triangles or quadrilaterals, is a cornerstone of numerical analysis and computational physics. While traditional methods rely on complex, fixed heuristics, this talk introduces a new paradigm: formulating mesh generation as an optimal decision-making process solved using Deep Reinforcement Learning (RL). I will present two distinct data-driven approaches to this problem, each targeting a different aspect of mesh construction: 1) Topology Optimization: The first approach focuses on finding the optimal connectivity. Starting from a basic mesh, we formulate a "game" where an RL agent learns to apply topological moves (such as edge flips) to maximize the number of regular nodes. This method is particularly effective for generating high-quality block decompositions for both triangular and quadrilateral meshes. 2) Geometry and Node Placement: The second approach focuses on vertex distribution. Here, a Graph Neural Network (GNN) learns a policy to insert, delete, and move vertices within the domain, while relying on a standard Delaunay algorithm to handle the triangulation. We will explore the design choices behind these "learning-to-mesh" frameworks and demonstrate that they can autonomously produce meshes that rival or exceed the quality of classical algorithms like DistMesh and Triangle.

See our Math Monday page for past talks!

Resource of the Day

Liza Jacoby, a graduate student representative on the equity and inclusion committee, has weekly office hours Wednesdays, 9:00 AM–11:00AM at Evans 1057. This is a safe and confidential space to talk about experiences and bring up issues to the department.

Check our our resources page for more!

About MUSA

Berkeley's Mathematics Undergraduate Student Association is an organization representing the undergraduate community in the math department.

We strive to improve the overall quality of studying mathematics here as an undergraduate, especially by advocating for issues that benefit the entire undergraduate math community, not only the subset that attends our events.

If you want to stay involved, make sure to suscribe to our mailing list and Google Calendar (see below), and also join our Discord and Instagram (@musaberkeley)!

Weekly Events

We hold events every week in Evans 1015 , the top floor lounge of Evans Hall. Our upcoming events are posted on our mailing list, Discord, and calendar (see below).
Some of our regular events, which are open to everyone, include:

• Thursday social events, held at 6:30pm
• Math Mondays at 5pm , where professors speak on a wide variety of mathematical topics
• Student-faculty lunches
• Homework parties every Wednesday at 1:30pm

We also host special events each semester, such as the Pauline Sperry lecture and the student-faculty dinner.

Lounge

The MUSA Lounge, 938 Evans, is open 10am–5pm on weekdays, selling hoodies and cheap food. People often come by just to chat about math or life. Come stop by—we won't bite!

We also have a library of math books you can borrow. See the lounge page for more details on the library as well as the merch preorder form.

If you can't hang out with us in person, join our Discord server to chat and get to know the MUSA community!

Mailing List and Calendar

Most announcements are done over MUSA's mailing list, which goes out every Sunday.

You can also view our event calendar here! Click the plus symbol at the bottom right to add it to your own Google Calendar or use this iCal link to add it to your own calendar application!

Merch

Looking to upgrade your outfit? We sell t-shirts, hoodies, and (recent addition) long sleeve shirts! Find them on our merch page!

How do I join MUSA?

There is no formal process to join the club! Just show up to as many events as you want, sign up for the mailing list, and get to know the math community at Berkeley! Our events are open to the public, not just declared math majors — so don't be a stranger!

Joining MUSA is an excellent way to connect with other math enthusiasts. You can learn about the many opportunities for math students, including little tricks that will help you survive the rigorous math curriculum here.

Don't forget to sign up for our mailing list and join our Discord and Instagram (@musaberkeley)!

Other Info

MUSA strives to make the math department as inclusive as possible. How are we doing? Let us know with our anonymous feedback form.