e rard Rauzy (1938 - 2010) Christian Mauduit (1958 - 2019) Grands - - PowerPoint PPT Presentation

G´ erard Rauzy (1938 - 2010) Christian Mauduit (1958 - 2019) Grands math´ ematiciens et bons folˆ atres

S´ ebastien FERENCZI Au moins sera de moy memoire Telle qu’il est d’ung bon folastre (Fran¸ cois Villon).

folˆ atrer = to frolick

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ǫ=Galien

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Disclaimer This is not un expos´ e ` a l’am´ ericaine.

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Beginnings CM attended Ecole des Mines de St-Etienne and enjoyed graph theory and arithmetics. During a dinner at Etienne:

• Go to Luminy, ask for Momo, I am the dean!

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How did they meet? CM -> Diplˆ

• me d’Etudes Approfondies en Math´

ematiques : Logique et Alg` ebre, 1981, not with GR. Then? ” Very early CM had a taste for number theory, he liked its simple statements and conjectures. He appreciated GR’s quietness, demureness, and pedagogical talents” .

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PhDs of CM with GR Doctorat de 3-` eme cycle de Math´ ematiques : ” Automates finis et ´ equir´ epartition modulo un” , 1984. Doctorat de Math´ ematiques : ” R´ epartition modulo un des suites automatiques” , 1986. GR wanted

it to be a Doctorat d’Etat

Habilitation ` a Diriger des Recherches : ” Substitutions et ensembles normaux” , Universit´ e Aix- Marseille II, 1989.

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A special bond CM and GR always used vous between them and tu with anybody else. Going from the seminar in St Charles to Le Pharo for some politicking: race between CM and GR’s cars in the streets (SF not amused). Politically: left of the left of the left.

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GR and Teichm¨ uller Simultaneous approximation of several real numbers -> The Rauzy induction on interval exchages (1979) -> The Rauzy - Veech cocycle -> Teichm¨ uller geometry. But Un expos´ e de Veech, c’est vite chiant (GR).

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GR and arithmetics Repartition modulo 1, normal numbers and sets. Propri´ et´ es statistiques des suites arithm´ etiques, PUF, 1976.

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Creation of an Institute in Luminy Laboratoire de Math´ ematiques Discr` etes (1992) (then IML, now I2M). SF, CM, GR

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Hiring of Bernard Host Skillful handling of the hiring committee by CM and GR. Hiring of Pierre Arnoux Meeting him at the airport, forcing their way through a complete blockade by lorry drivers. No problem with the committee, no other candidate made it to the interview.

A trip to Alger (1989) GR (at the airport): I have a news for you: I shall not go, I forgot my passport. CM: no problem, call your wife, she can bring it if she drives fast - and first look in your car. (passport found in car) CM (emerging from a shrieking crowd, many people loaded with car tyres): I have our boarding cards. SF (mode ” ¸ ca va rater patron” ): these are for Annaba, we are going to Alger. CM (re-emerging from the same crowd): the flight to Alger had just been closed, I convinced them to re-open it.

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How to return from Alger

• Have fake plane tickets emitted by CM’s aunt’s travel agency.
• Have GR transform the fake bookings into real ones through high-level connections dating from

the Algeria independence war.

• Explain a Swiss mathematician how it works.

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Two innovative taechers Outstanding teachers who did not like the routine of teaching ” service” . GR’s solution: the Rauzy reduction. Minimize the number of hours actually taught, by various means including:

• ops, sorry, I forgot, I made lectures of 3 hours instead of 4.

CM’s solution: pedagogy and vulgarization. Replace some courses by workshops with schoolchildren. Also, make the last lectures after the final examination.

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End of the glory days The coup I call La conjuration des imb´ eciles (A confederacy of dunces) (1994) Administrative mistakes -> GR accused of loose day-to-day management. SF and CM choose this time to go to a conference in Hawa¨ ı. GR politely persuaded to leave the direction of his team to a more honest man. Then GR lost interest successively in politics, mathematics, life; CM went off to new adventures,

• ften based on samba.

BUT THE INSTITUTE IS ALIVE AND WELL and (at this moment) ruled by the next generation in the Rauzy-Mauduit line of descent.

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