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Kéva Djambaé

Doctoral Researcher in mathematics
Email : djambae at gaati.org
GAATI Laboratory
University of French Polynesia
BP 6570 — 98702 Faaa
French Polynesia

Research

Research Interest

PhD studies are conducted under the supervision of Gaetan Bisson and David Kohel, member of the GAATI laboratory at the University of French Polynesia and of the Arithmetic and Information Theory (ATI) team within the Institute of Mathematics of Marseille (I2M).
A brief curriculum vitae is available here.

Research focuses on arithmetic geometry, a field at the intersection of algebraic number theory and algebraic geometry. The Master's thesis explored the generalization of the Kronecker-Weber theorem in the context of totally imaginary quadratic extensions, leveraging elliptic curves with complex multiplication. The thesis and a summary (in English) are available below:

• A summary of the Master's thesis

My current research focuses on elliptic curves, offering deep insights into the arithmetic structure of finite, local, and global fields.
I am equally interested in both the computational and theoretical aspects, primarily using SageMath to perform effective calculations in number theory. My work is based on a combination of class field theory and scheme theory, allowing me to navigate between these two frameworks to explore the interactions between arithmetic invariants, field extensions, and geometric objects. I also develop algorithmic methods for a concrete and rigorous study of these interactions, while promoting an abstract and unified approach.

Talks

I have given several talks in various academic and outreach settings:

• A research seminar at the GAATI laboratory on May 13, 2025, entitled "Galois Action and Elliptic Curves" (notes to be published shortly), where I presented both my annual research progress and my Master's thesis work.
• A presentation at the 2025 UPF Doctoral Conference, aimed at a general audience. A recording is available here (my presentation starts at 27:30)
• I organized a mathematical outreach workshop at the École de la Deuxième Chance in Marseille, at the invitation of J. Youssef, on July 22, 2022.

Publications

Forthcoming

Teaching

2025/2026

In 2024/2025, I taught at the University of French Polynesia (UPF) in three tutorial sessions (TD) for the first year of the Mathematics – Engineering Sciences program.
The tutorial sheets were written by the professors in charge of the lectures:

First semester

• Numerical and Algebraic Calculus
  • Lecture given by Jean Vallès
  • Document to be published soon

Second semester

• Matrix Calculus
  • Lecture given by Prescillia Tcheou
  • Document to be published soon

2024/2025

For the 2024/2025 academic year, tutorials are taught at the University of French Polynesia (UPF) as part of the first-year Bachelor's degree program for the Mathematics - Science for Engineering portal.
The tutorial sheets were written by those responsible for the lectures:

• Integral Calculus
  • Lecture course taught by Jean Vallès
  • TD 1
  • TD 2
  • TD 3
  • Review sheet
  • TD 4
  • Review sheet 2 (made by Christophe Raffali and myself)
• Matrix Calculations
  • Lecture course taught by Prescillia Tcheou
  • TD (without correction)

2023/2024

Teaching experience began at Lycée Honoré Daumier in Marseille, with responsibilities including a classe de seconde générale and two classes de première spécifique during the CAPES internship. Lecture notes (in French and partially complete due to time constraints) are provided below:

• Seconde générale 2023/2024
• Première spécifique 2023/2024

Institutional Commitments

Research Commission

Elected member representing PhD students of the Sciences, Technologies and Health (STS) sector to the Research Commission of the University of French Polynesia (2025–2027 term), contributing to discussions on scientific orientations, research evaluation and support, as well as doctoral student representation.

Disciplinary Commission

Elected member (students’ section) of the Disciplinary Commission of the University of French Polynesia (2025–2027 term), contributing to deliberations concerning compliance with academic obligations, the review of disciplinary matters, and the safeguarding of students’ rights.