Profinite completions of Burnside-type quotients of surface groups

Using quantum representations of mapping class groups we prove that profinite completions of Burnside-type surface group quotients are not virtually prosolvable, in general. Further, we construct infinitely many finite simple characteristic quotients of surface groups.Comment: revised version, 17

Profinite complexes of curves, their automorphisms and anabelian properties of moduli stacks of curves

Let ${\cal M}_{g,[n]}$, for $2g-2+n>0$, be the D-M moduli stack of smooth curves of genus $g$ labeled by $n$ unordered distinct points. The main result of the paper is that a finite, connected \'etale cover {\cal M}^\l of ${\cal M}_{g,[n]}$, defined over a sub-$p$-adic field $k$, is "almost" anabelian in the sense conjectured by Grothendieck for curves and their moduli spaces. The precise result is the following. Let \pi_1({\cal M}^\l_{\ol{k}}) be the geometric algebraic fundamental group of {\cal M}^\l and let {Out}^*(\pi_1({\cal M}^\l_{\ol{k}})) be the group of its exterior automorphisms which preserve the conjugacy classes of elements corresponding to simple loops around the Deligne-Mumford boundary of {\cal M}^\l (this is the "$\ast$-condition" motivating the "almost" above). Let us denote by {Out}^*_{G_k}(\pi_1({\cal M}^\l_{\ol{k}})) the subgroup consisting of elements which commute with the natural action of the absolute Galois group $G_k$ of $k$. Let us assume, moreover, that the generic point of the D-M stack {\cal M}^\l has a trivial automorphisms group. Then, there is a natural isomorphism: {Aut}_k({\cal M}^\l)\cong{Out}^*_{G_k}(\pi_1({\cal M}^\l_{\ol{k}})). This partially extends to moduli spaces of curves the anabelian properties proved by Mochizuki for hyperbolic curves over sub-$p$-adic fields.Comment: This paper has been withdrawn because of a flaw in the paper "Profinite Teichm\"uller theory" of the first author, on which this paper built o

Elliptic multizetas and the elliptic double shuffle relations

We define an elliptic generating series whose coefficients, the elliptic multizetas, are related to the elliptic analogues of multiple zeta values introduced by Enriquez as the coefficients of his elliptic associator; both sets of coefficients lie in $\mathcal{O}(\mathfrak{H})$, the ring of functions on the Poincar\'e upper half-plane $\mathfrak H$. The elliptic multizetas generate a $\mathbb Q$-algebra $\mathcal{E}$ which is an elliptic analogue of the algebra of multiple zeta values. Working modulo $2\pi i$, we show that the algebra $\mathcal{E}$ decomposes into a geometric and an arithmetic part and study the precise relationship between the elliptic generating series and the elliptic associator defined by Enriquez. We show that the elliptic multizetas satisfy a double shuffle type family of algebraic relations similar to the double shuffle relations satisfied by multiple zeta values. We prove that these elliptic double shuffle relations give all algebraic relations among elliptic multizetas if (a) the classical double shuffle relations give all algebraic relations among multiple zeta values and (b) the elliptic double shuffle Lie algebra has a certain natural semi-direct product structure analogous to that established by Enriquez for the elliptic Grothendieck-Teichm\"uller Lie algebra.Comment: major revision, to appear in: Int. Math. Res. No

Dualité de sexe et dualité de genre dans les normes juridiques

L’objet de cette étude n’est pas d’analyser pour eux-mêmes les rapports sociaux de sexe ni même la façon dont le droit entérine ou induit ces rapports, mais de repérer les endroits et les moments où la règle de droit est « sexuée » ou à l’inverse « aveugle au sexe » – « genderblind », comme on dit « colorblind ». Nous nous intéresserons aux contextes dans lesquels le droit prend (ou ne prend pas) en compte la dimension du sexe et du genre, attache des conséquences juridiques à la distinction homme/femme, autrement dit érige les «hommes» et les « femmes » en catégories juridiques, ainsi qu’aux raisons qui peuvent expliquer que, selon les cas, l’appartenance à l’un ou l’autre sexe constitue ou non une donnée juridiquement pertinente

No Drama Quantum Theory?

This work builds on the following result of a previous article (quant-ph/0509044): the matter field can be naturally eliminated from the equations of the scalar electrodynamics (the Klein-Gordon-Maxwell electrodynamics) in the unitary gauge. The resulting equations describe independent dynamics of the electromagnetic field (they form a closed system of partial differential equations). An improved derivation of this surprising result is offered in the current work. It is also shown that for this system of equations, a generalized Carleman linearization (Carleman embedding) procedure generates a system of linear equations in the Hilbert space, which looks like a second-quantized theory and is equivalent to the original nonlinear system on the set of solutions of the latter. Thus, the relevant local realistic model can be embedded into a quantum field theory. This model is equivalent to a well-established model - the scalar electrodynamics, so it correctly describes a large body of experimental data. Although it does not describe the electronic spin and possibly some other experimental facts, it may be of great interest as a "no drama quantum theory", as simple (in principle) as classical electrodynamics. Possible issues with the Bell theorem are discussed.Comment: 4 page