What galaxy masses perturb the local cosmic expansion?

What Is the Cosmic-ray Luminosity of Our Galaxy?

The total cosmic-ray luminosity of the Galaxy is an important constraint on models of cosmic-ray generation. The diffuse high energy γ-ray and radio-synchrotron emissions of the Milky Way are used to derive this luminosity. The result is almost two orders of magnitude larger than the standard estimate, based on the observed isotopic abundances of cosmic ray nuclides. We discuss the plausible in...

Local perturbations perturb locally

What Best Constrains Galaxy Evolution in the Local Universe?

After a polemical introduction about the proper activity of an astrophysicist facing a dominant theoretical model and many Tb of highly informative data, I review a few recent results on the properties of galaxies in the nearby (redshift one-tenth) Universe that directly bear on physical cosmology. In one example, I show that there are a number of ways of measuring, or strongly constraining, ma...

Gravitationaìconvergence' and Galaxy Cluster Masses

Two colour photometry of the cluster A1689 reveals a `relative magniication-bias' between lensed blue and red background galaxies, arising from a dependence of the faint galaxy count-slope on colour. The colour distribution is skewed blueward of the far eld, allowing us to measure the cluster magniication and to understand the notorious blueness of large arcs. We show that the magniication info...

Local Perturb-and-MAP for Structured Prediction

Conditional random fields (CRFs) provide a powerful tool for structured prediction, but cast significant challenges in both the learning and inference steps. Approximation techniques are widely used in both steps, which should be considered jointly to guarantee good performance (a.k.a. “inferning"). Perturb-and-MAP models provide a promising alternative to CRFs, but require global combinatorial...