Eulerian digraphs and toric Calabi-Yau varieties

We investigate the structure of a simple class of affine toric Calabi-Yau varieties that are defined from quiver representations based on finite eulerian directed graphs (digraphs). The vanishing first Chern class of these varieties just follows from the characterisation of eulerian digraphs as being connected with all vertices balanced. Some structure theory is used to show how any eulerian digraph can be generated by iterating combinations of just a few canonical graph-theoretic moves. We describe the effect of each of these moves on the lattice polytopes which encode the toric Calabi-Yau varieties and illustrate the construction in several examples. We comment on physical applications of the construction in the context of moduli spaces for superconformal gauged linear sigma models.Comment: 27 pages, 8 figure

Poetry, resistance, world-literature : Adília Lopes and Marie Buck

This essay begins an exploration of how poetry functions within the field of world-literature, drawing specifically on the Warwick Research Collective’s Combined and Uneven Development: Towards a New Theory of World-Literature and reflecting comparatively on the poetry of Adília Lopes and Marie Buck. Even though there are many differences between the two authors and their works, one common feature of their poetics is the deployment of poetry as a form of resistance. As such, both can be seen as especially significant so as to probe into the condition of poetry within a conceptualization of world-literature understood as the literature of the capitalist world-system. As the essay argues, both Adília Lopes and Marie Buck register specific conditions of oppression within a capitalist, patriarchal, society and offer ways to contest them

Neutrino Mixing in Unified Extended Seesaw Model

The seesaw mechanism can play a key role in the generation of the leptonic mixing in unified models. We consider an unified model with a family symmetry and extended seesaw, and obtain viable fermion masses and mixing (leptonic mixing is close to tri-bi-maximal).Comment: Proceedings submission for SUSY09, 4 pages, 1 figur