Symmetries of quasiplatonic Riemann surfaces

We state and prove a corrected version of a theorem of Singerman, which relates the existence of symmetries (anticonformal involutions) of a quasiplatonic Riemann surface $\mathcal S$ (one uniformised by a normal subgroup $N$ of finite index in a cocompact triangle group $\Delta$) to the properties of the group $G=\Delta/N$. We give examples to illustrate the revised necessary and sufficient conditions for the existence of symmetries, and we relate them to properties of the associated dessins d'enfants, or hypermaps

A series of coverings of the regular n-gon

We define an infinite series of translation coverings of Veech's double-n-gon for odd n greater or equal to 5 which share the same Veech group. Additionally we give an infinite series of translation coverings with constant Veech group of a regular n-gon for even n greater or equal to 8. These families give rise to explicit examples of infinite translation surfaces with lattice Veech group.Comment: A missing case in step 1 in the proof of Thm. 1 b was added. (To appear in Geometriae Dedicata.

Riemann Surfaces of genus g with an automorphism of order p prime and p>g

The present work completes the classification of the compact Riemann surfaces of genus g with an analytic automorphism of order p (prime number) and p > g. More precisely, we construct a parameteriza- tion space for them, we compute their groups of uniformization and we compute their full automorphism groups. Also, we give affine equations for special cases and some implications on the components of the singular locus of the moduli space of smooth curves of genus g.Comment: 28 pages, 5 figure

A Tonnetz Model for pentachords

This article deals with the construction of surfaces that are suitable for representing pentachords or 5-pitch segments that are in the same $T/I$ class. It is a generalization of the well known \"Ottingen-Riemann torus for triads of neo-Riemannian theories. Two pentachords are near if they differ by a particular set of contextual inversions and the whole contextual group of inversions produces a Tiling (Tessellation) by pentagons on the surfaces. A description of the surfaces as coverings of a particular Tiling is given in the twelve-tone enharmonic scale case.Comment: 27 pages, 12 figure

Neither participation nor revolution: the strategy of the Moroccan Jamiat al-Adl wal-Ihsan

Scholars and students of Islamist movements are divided over the issue of Islamists' commitment to democracy and a number of studies have attempted to discover the true nature of Islamist parties. This paper rejects this approach and argues that the behaviour of Islamist parties can be better understood through an analysis of the constraints and opportunities that their surrounding environment provides. Specifically, the paper aims at explaining the choice of the Moroccan Jamiat al-Adl wal-Ihsan neither to participate in institutional politics nor to undertake violent actions to transform the regime. This is done through an examination of its relations with the other political actors. The paper argues that Jamiat al-Adl wal-Ihsan's behaviour is as much the product of rational thinking as it is of ideology and provides evidence to support this claim. Such findings are important not only in the Moroccan context, but contribute to a growing literature claiming that Islamist movements should be treated as rational political actors operating under 'environmental' constraints and opportunities

Purely (Non-)Strongly Real Beauville Groups

We discuss Beauville groups whose corresponding Beauville surfaces are either always strongly real or never strongly real producing several infinite families of examples

Egyptian Satirical Graphics on Social Media after the Arab Spring

This paper investigates Egyptian digital forms of satirical graphics mostly published on Social Media by cartoonists and amateurs after the Arab Spring. These include: webcomics memes, and Graphic Interchange Format (GIF). The paper will focus on two Facebook pages as a case study: Asa7be Sarcasm Society and Islam Gawish's Elwarka/The Paper. With this aim in mind, I will show how these forms of political satire incorporate, cinema, theatre, religion, western elements and pan-Arabism to express a political view in a creative manner to appeal to a more diverse and broad audience. The first part of the paper provides a brief discussion of Arabic/Egyptian satire with specific reference to political cartoons and Egyptian youth activism on social media (specifically Facebook). It will also introduce the concept of satirical graphics and some of its concrete applications. The second part describes the methodology and provides an analysis of the case study