KSZ tomography and the bispectrum

Several statistics have been proposed for measuring the kSZ effect by combining the small-scale CMB with galaxy surveys. We review five such statistics, and show that they are all mathematically equivalent to the optimal bispectrum estimator of type $\langle ggT \rangle$. Reinterpreting these kSZ statistics as special cases of bispectrum estimation makes many aspects transparent, for example optimally weighting the estimator, or incorporating photometric redshift errors. We analyze the information content of the bispectrum and show that there are two observables: the small-scale galaxy-electron power spectrum $P_{ge}(k_S)$, and the large-scale galaxy-velocity power spectrum $P_{gv}(k)$. The cosmological constraining power of the kSZ arises from its sensitivity to fluctuations on large length scales, where its effective noise level can be much better than galaxy surveys.Comment: 39 page

Occupation Statistics of a BEC for a Driven Landau-Zener Crossing

We consider an atomic Bose-Einstein condensate (BEC) loaded in a biased double-well trap with tunneling rate $K$ and inter-atomic interaction $U$. The BEC is prepared such that all $N$ atoms are in the left well. We drive the system by sweeping the potential difference $\epsilon$ between the two wells. Depending on the interaction $u=NU/K$, and the sweep rate $\dot{\epsilon}$, we distinguish three dynamical regimes: adiabatic, diabatic, and sudden, and consider the occupation statistics of the final state. The analysis goes beyond mean-field theory and is complemented by a semiclassical picture.Comment: 4 pages, 5 figure

Alcohol exposure impairs trophoblast survival and alters subtype-specific gene expression in vitro

Maternal alcohol consumption is common prior to pregnancy recognition and in the rat results in altered placental development and fetal growth restriction. To assess the effect of ethanol (EtOH) exposure on the differentiation of trophoblast stem (TS) cells, mouse TS lines were differentiated in vitro for 6 days in 0%, 0.2% or 1% EtOH. This reduced both trophoblast survival and expression of labyrinth and junctional zone trophoblast subtype-specific genes. This suggests that fetal growth restriction and altered placental development associated with maternal alcohol consumption in the periconceptional period could be mediated in part by direct effects on trophoblast development. (C) 2016 Elsevier Ltd. All rights reserved

“The first man on the street” - tracing a famous Hilbert quote (1900) back to Gergonne (1825)

A short, catchy, and in its content somewhat exaggerated, quote allows us to draw a connection through three-quarters of a century between two leaders of mathematics who apparently held somewhat similar philosophical, pedagogical, and political views. In addition to providing some new facets to the biographies of Gergonne and Hilbert, our article relates to increasing demands for the dissemination of mathematical knowledge and to corresponding structural changes within mathematics during the 19th century