Global environmental governance: the challenge of accountability

This repository item contains a single issue of Sustainable Development Insights, a series of short policy essays that began publishing in 2008 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. The series seeks to promote a broad interdisciplinary dialogue on how to accelerate sustainable development at all levels.This issue argues that accountability – or lack thereof- is a fundamental challenge in confronting improved global environmental governance (GEG) and that success must be measured not simply by the vitality of the negotiation process but by the robustness of implementation. States as well as institutions must be judged not by their statements of good intentions but by measurable implementation of their commitments and achievement of goals. The authors provide five reasons for GEG’s culture of unaccountability and seven related ideas for GEG reform

Influence of baryonic physics in galaxy simulations: a semi-analytic treatment of the molecular component

Recent work in galaxy formation has enlightened the important role of baryon physics, to solve the main problems encountered by the standard theory at the galactic scale, such as the galaxy stellar mass functions, or the missing satellites problem. The present work aims at investigating in particular the role of the cold and dense molecular phase, which could play a role of gas reservoir in the outer galaxy discs, with low star formation efficiency. Through TreeSPH simulations, implementing the cooling to low temperatures, and the inclusion of the molecular hydrogen component, several feedback efficiencies are studied, and results on the gas morphology and star formation are obtained. It is shown that molecular hydrogen allows some slow star formation (with gas depletion times of about 5 Gyr) to occur in the outer parts of the discs. This dense and quiescent phase might be a way to store a significant fraction of dark baryons, in a relatively long time-scale, in the complete baryonic cycle, connecting the galaxy discs to hot gaseous haloes and to the cosmic filaments.Comment: Accepted for publication in Astronomy and Astrophysics, 21 pages, 29 figure

Motivic zeta functions of degenerating Calabi-Yau varieties

We study motivic zeta functions of degenerating families of Calabi-Yau varieties. Our main result says that they satisfy an analog of Igusa's monodromy conjecture if the family has a so-called Galois-equivariant Kulikov model; we provide several classes of examples where this condition is verified. We also establish a close relation between the zeta function and the skeleton that appeared in Kontsevich and Soibelman's non-archimedean interpretation of the SYZ conjecture in mirror symmetry.Comment: New result on existence of Kulikov models for abelian varieties added in section 5.

Jumps and monodromy of abelian varieties

We prove a strong form of the motivic monodromy conjecture for abelian varieties, by showing that the order of the unique pole of the motivic zeta function is equal to the size of the maximal Jordan block of the corresponding monodromy eigenvalue. Moreover, we give a Hodge-theoretic interpretation of the fundamental invariants appearing in the proof.Comment: Section 5 rewritten, Section 6 expande