Here you will find all of my contributions and participations to mathematical research. This is about knot theory and connected fields mostly. All articles are in English (sometimes with a French summary), but the thesis and almost all slideshows are written in French language. Also, titles of conferences or events are not translated.

Ph.D Thesis

2022 - Thèse.pdf

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Enchevêtrements et polynôme de Jones modulaire
Tangles and modular Jones polynomial

Université du Littoral Côte d'Opale (ULCO)
Laboratoire de Mathématiques Pures et Appliquées Joseph Liouville (
LMPA)
Supervised by
Prof. Eliahou, Shalom and M.C. Fromentin, Jean
Started on 2018-09-26, defended on 2021-12-06, published on 2022-03-29.

A knot is a circle tied in the three dimensional space which can be deformed continuously. In order to distinguish knots, a bundle of invariants have been developed. Among them, the Jones polynomial (1985) is one of the most famous and studied. Surprisingly, its hability to detect the unknot is not decided yet. Recently, a paper from Eliahou and Fromentin (2017) shows a new point of view for this problem. By considering the Jones polynomial modulo an integer m, the existence of non-trivial knots seen as the unknot by this polynomial invariant is more approachable. Their work also presents an answer for the cases m=2^r. In this memoir, we show that it is possible to construct knots to answer cases m^r from one having a trivial Jones polynomial modulo m. That allows to give an other answer for cases m=2^r, but also for cases m=3^r. We try to give a generalized construction of the Eliahou and Fromentin one too, but the lack of examples make this only theoretical so far.

The Kauffman bracket (1987) is a tool to construct the Jones polynomial from a knot diagram. Its connections with generators of the Temperley-Lieb algebra, which also span the diagram monoid, and the braid theory have already been studied, notably by Kauffman himself (1990). We continue to investigate these different connections so that we can learn more on the Jones polynomial, and on these connected theories too. We bring as example a new matrix representation of braids, which provide a new method to compute the Jones polynomial associated to these braids closed in various way. We also study the diagram monoid thank to an embedding inside permutations, and develop as such a new product for permutations similar to the classical composition.

Articles

  • 2022 - A new product over the permutations to represent the Kauffman monoid. Work in progress.

  • 2020 - On the modular Jones polynomial. Comptes Rendus. Mathématique, Tome 358 (2020) no. 8, pp. 901-908. (Original - ArXiv - HAL)
    A major problem in knot theory is to decide whether the Jones polynomial detects the unknot. In this paper we study a weaker related problem, namely whether the Jones polynomial reduced modulo an integer m detects the unknot. The answer is known to be negative for m=2^r with r⩾1 and m=3. Here we show that if the answer is negative for some m, then it is negative for m^r with any r⩾1. In particular, for any r⩾1, we construct nontrivial knots whose Jones polynomial is trivial modulo 3^r.

Conferences

Events

  • 01 July 2021 - Journée des doctorants du pôle MTE (Calais, France) - Thesis introduction within 180 seconds with only one slide to a non expert audience.

  • 08 October 2019 - Fête de la science (Calais, France) - Scientific workshop for school children.

Scientific poster and slideshows

2021 - Soutenance.pdf
(2021-12-06) Ph.D defence
That was such an incredible experience. I've learnt so many things, including the most important one: there is still so much more to learn.
2021 - MT180.pdf
(2021-07-01) Journée des doctorants du pôle MTE
One slide and 180 seconds to talk about the Jones polynomial and its modular version for either experts and non scientific public.
2020 - Diaporama Journée Doctorant.pdf
(2020-09-11) 14ème Journée des Doctorants en Mathématiques de la région Hauts-de-France
Presentation of two years of work in front of most of all mathematical doctoral students of my region.
2019 - Poster Inter-action.pdf
(2019-05-20) Colloque Inter'Actions
First output of my work, presenting my thesis problematic and my first result. This result was later published in my very first scientific paper.