Simple cosmological de Sitter solutions on {\rm dS}_4 \times {\rm \mbox{{Y}}}_6 spaces

Simple de Sitter Solutions

We present a framework for de Sitter model building in type IIA string theory, illustrated with specific examples. We find metastable dS minima of the potential for moduli obtained from a compactification on a product of two Nil three-manifolds (which have negative scalar curvature) combined with orientifolds, branes, fractional Chern-Simons forms, and fluxes. As a discrete quantum number is ta...

Minimal simple de Sitter solutions

We show that the minimal set of necessary ingredients to construct explicit, four-dimensional de Sitter solutions from IIA string theory at tree level are O6-planes, nonzero Romans mass parameter, form fluxes, and negative internal curvature. To illustrate our general results, we construct such minimal simple de Sitter solutions from an orientifold compactification of compact hyperbolic spaces....

Topological superconductor in quasi-one-dimensional ${\rm Tl}_{2-x}{\rm Mo}_6{\rm Se}_6$

Identifying an Honest ${\rm EXP}^{\rm NP}$ Oracle Among Many

We provide a general framework to remove short advice by formulating the following computational task for a function f : given two oracles at least one of which is honest (i.e. correctly computes f on all inputs) as well as an input, the task is to compute f on the input with the help of the oracles by a probabilistic polynomial-time machine, which we shall call a selector. We characterize the ...

Bank ownership, rm value and rm capital structure in Europe*

We investigate the role of banks in the ownership structure of non-…nancial …rms. Distinguishing between banks and other institutional investors as shareholders, we examine the relationship between …nancial institution ownership and the performance of the …rms in which they hold equity. We control explicitly for the capital structure decision of the …rms and the ownership decision of …nancial i...