# Cosmologie

# Kinetic Inductance Detectors (KIDs)

Kinetic inductance detector (KID) is a promising technology for astronomy with high sensitivity, microsecond timing and intrinsic multiplexing readout properties. Based on these advantages, a wide range of application has been proposed from millimeter to X-ray. With simple fabrication and frequency domain multiplexing readout, hundreds of KID pixels could be easily read out with single cable. In the last decade, KID has been developed rapidly. This talk will introduce the recent development of KIDs for frequency range from 100 GHz to 1 THz.

# Studying black hole populations with gravitational-wave observations

The first observations of gravitational waves emitted by merging binary black holes demonstrated the existence of black holes more massive than ever observed in our Galaxy. Future observations with ground-based interferometers such as Advanced LIGO and Virgo will probe the mass and spin distributions of black holes in various galactic environments and may also detect the stochastic gravitational-wave background from unresolved mergers. These measurements will provide a new tool for stellar and galaxy evolution studies.

# Physics of Gravitational Redshifts in Clusters of Galaxies

Wojtak, Hansen and Hjorth and others have measured the long-predicted gravitational redshift of light escaping from galaxy clusters. The effect is very small, corresponding to a velocity shift of only ~10 km/s, but the result appears to be fairly robust and seemed to be in good agreement with general relativity predictions and possibly in conflict with some alternative theories. The effect was initially imagined to be a simple astronomical analogue of the famous terrestrial Pound and Rebka experiment that verified Einstein's theoretical prediction.

# Weak Lensing Peak Counts and New Statistical Methods

Martin Kilbinger (CEA) will speak with us about weak-lensing peak counts, and a new statistical method that he has been using lately called Approximate Bayesian Computation (ABC). This is a likelihood-free parameter inference technique which is gaining popularity in cosmology, so it might be interesting for a wider audience than just weak lensing.

# The Dark Energy Survey Supernova Program and the Australian OzDES survey

# LSST/Euclid Synergy

Eric Aubourg will discuss LSST/Euclid synergy and give an update on recent negotiations between the two. See also https://arxiv.org/abs/1710.08489.

# Probing dark energy with cosmic voids

Cosmic voids can supply powerful insights into the nature of dark energy, provided that we have accurate models of their statistical properties. In this talk I will present a new method to identify and predict void density profiles, and show how we can reduce systematic errors when probing the growth rate around voids. This will be crucial for testing non-standard dark energy models with upcoming large survey campaigns.

# Possible consequences in Cosmology from the vector-like SU(3) family symmetry model

Extension of the Standard Model (SM) by gauged SU(3) symmetry of families involves new physics at high energy scales. Even elusive from direct experimental probes, such construction can be tested in the combination of Particle physics, Astrophysics and Cosmological signatures. We point out possible Cosmological impact of the new scalars, gauge bosons and vector-like quarks and leptons, including sterile neutrinos, of the vector-like SU(3) family symmetry.

# Robust but enigmatic post-Planck Cosmos

The widely heralded and remarkable progress in cosmology leading to the emergence of a 'standard cosmological model’ has relied on certain key assumptions at various levels. I review work along multiple facets, largely, from the research program of my group at IUCAA, that have all attempted to adopt an agnostic approach in drawing cosmological inference independent of such assumptions, in the context of the exquisite observations of the Cosmic Microwave Background CMB anisotropy by Planck. I dwell on the enigmatic