Cosmological constraints from the BOSS DR12 void size function


We present the first cosmological constraints derived from the analysis of the void size function. This work relies on the final BOSS DR12 data set, a large spectroscopic galaxy catalog, ideal for the identification of cosmic voids. We extract a sample of voids from the distribution of galaxies and we apply a cleaning procedure aimed at reaching high levels of purity and completeness. We model the void size function by means of an extension of the popular volume-conserving model, based on two additional nuisance parameters. Relying on mock catalogs specifically designed to reproduce the BOSS DR12 galaxy sample, we calibrate the extended size function model parameters and validate the methodology. We then apply a Bayesian analysis to constrain the ΛCDM model and one of its simplest extensions, featuring a constant dark energy equation of state parameter, w. Following a conservative approach, we put constraints on the total matter density parameter and the amplitude of density fluctuations, finding Ωm=0.29+0.07−0.06 and σ8=0.80+0.09−0.08. Testing the alternative scenario, we derive w=−1.1±0.3, in agreement with the ΛCDM model. These results are independent and complementary to those derived from standard cosmological probes, opening up new ways to identify the origin of potential tensions in the current cosmological paradigm.

**A Novel JupyterLab User Experience for Interactive Data Visualization


In the Jupyter ecosystem, data visualization is usually done with “widgets” created as notebook cell outputs. While this mechanism works well in some circumstances, it is not well-suited to presenting interfaces that are long-lived, interactive, and visually rich. Unlike the traditional Jupyter notebook system, the newer JupyterLab application provides a sophisticated extension infrastructure that raises new design possibilities. Here we present a novel user experience (UX) for interactive data visualization in JupyterLab that is based on an “app” that runs alongside the user’s notebooks, rather than widgets that are bound inside them. We have implemented this UX for the AAS WorldWide Telescope (WWT) visualization tool. JupyterLab’s messaging APIs allow the app to smoothly exchange data with multiple computational kernels, allowing users to accomplish tasks that are not possible using the widget framework. A new Jupyter server extension allows the frontend to request data from kernels asynchronously over HTTP, enabling interactive exploration of gigapixel-scale imagery in WWT. While we have developed this UX for WWT, the overall design and the server extension are portable to other applications and have the potential to unlock a variety of new user activities that aren’t currently possible in “science platform” interfaces.

A population of faint, old, and massive quiescent galaxies at 3 < z < 4 revealed by JWST NIRSpec Spectroscopy


Can Cosmological Simulations Reproduce the Spectroscopically Confirmed Galaxies Seen at z≥10?



Constraining Cosmic Inflation with Observations: Prospects for 2030


The ability to test and constrain theories of cosmic inflation will advance substantially over the next decade. Key data sources include cosmic microwave background (CMB) measurements and observations of the distribution of matter at low-redshift from optical, near-infrared, and 21cm intensity surveys. A positive detection of a CMB B-mode consistent with a primordial stochastic gravitational wave background (SGWB) is widely viewed as a smoking gun for an inflationary phase. Still, a null result does not exclude inflation. However, in a significant class of inflationary scenarios, a low SGWB amplitude is correlated with a more significant running, α**s, in the primordial density perturbations than is seen with the simplest inflationary potentials. With this motivation, we forecast the precision with which the spectral index ns and αs can be constrained by currently envisaged observations, including CMB (Simons Observatory, CMB-S4 and \textit{LiteBIRD}), optical/near infra-red (DESI and SPHEREx), and 21cm intensity mapping (Tianlai and CHIME) surveys. We identify optimal combinations of datasets for constraining the running and show that they may yield additional and informative constraints on the overall inflationary parameter space if the SGWB remains undetected.

Supermassive black hole seeds from sub-keV dark matter


Detecting Axion-Like Particles with Primordial Black Holes


Local Group Dwarf Galaxy Detection Limit in the CSST survey