We are working towards a formula that gives some lowerbound on the number of pseudo-holomorphic sections of a Lefschetz fibration over the disk, while keeping track of their relative homology class. To achieve this, we developed a particular local coefficient system and gave a fully explicit and geometric proof of the exactness of Seidel's triangle in Lagrangian and Fixed Point Floer homology.
I gave an explicit description of the Floer cohomology of a family of Dehn twists about disjoint Lagrangian spheres in a weakly+-monotone rational symplectic manifold. This is a generalization of a classic result by P. Seidel from 1996 and it is based on a neck-stretching argument and some delicate reasoning with an energy filtration for \(CF(\tau_V)\) which show that certain "bad trajectories" do not count towards the differentials for \(CF(\tau_V)\), proving that the chain complex can be naturally identified with the one for Morse relative cohomology of \((M,V)\).
This is my master thesis project, where I (almost) completely classified four-manifold with prescribed fundamental group up to stable diffeomorphism. As a corollary I got some restriction on the divisibility of the signature of such manifolds under some additional assumptions. A. Debray communicated me he was able to figure out the classification in the missing case.
We will share three mini-lessons for guiding mathematics majors to develop ethical reasoning skills. These activities have been tested, evaluated, and revised in a 1-hour seminar for entry-level mathematics majors over two recent offerings of this course. In the first activity, students collaboratively develop a set of Ethical Guidelines for Mathematics Majors. Then, in the second activity, students apply these guidelines to analyze vignettes posing an ethical challenge linked to being an undergraduate math major. Finally, in the third activity, students reflect on their experiences through the lens of the collaboratively developed Ethical Guidelines for Mathematics Majors. We hope our paper will be relevant for college and university mathematics instructors who wish to support the development of their students' ethical reasoning skills.