Conveners
Late Universe
- Camille Bonvin
Late Universe
- Camille Bonvin
Cosmic birefringence is the in-vacuo rotation of the linear polarization plane experienced by photons of the Cosmic Microwave Background (CMB) radiation when theoretically well-motivated parity-violating extensions of Maxwell electromagnetism are considered. If the angle parametrizing such a rotation is dependent on the photon's direction, then this phenomenon is called Anisotropic Cosmic...
The weak gravitation lensing of the Cosmic Microwave Background
(CMB) [1] rows a wealth of information about the late-time universe in the
CMB data we observe through ground-based and space-based telescopes.
In this talk, I propose a method to probe Galaxy-cluster mass profiles
from the lensing signature of CMB in arcmin scales. In the first part, I
describe how a theoretical halo model...
LSST will provide an unprecedented wealth of astronomical data, with which we will be able to tightly constrain the values of the cosmological parameters, notably those which describe the poorly understood dark energy component. As weak lensing and galaxy clustering measurements provide a way to infer key cosmological quantities such as the dark matter distribution, the evolution of cosmic...
As a result of the observed discrepancies within the $\Lambda \mathrm{CDM}$ model, a lot of work is being done to reconcile the observations from the early and late universe with new cosmological models. The resulting model testing is often based on inference algorithms that depend on a large number of computationally intensive simulations that conclude in large computational efforts.
In...
Galaxies are biased tracers of the underlying dark matter density field. If we work with a single tracer, its two-point function will be symmetric under exchange of the pair of galaxies under consideration. But if we look at two different tracers, then in principle their cross-correlation could be not symmetric (Dai et al. 2016). This locally antisymmetric signal arises naturally when the two...
We determine the dipole in the Pantheon+ data. We find that, while its amplitude roughly agrees with the dipole found in the cosmic microwave background which is attributed to the motion of the solar system with respect to the cosmic rest frame, the direction is different at very high significance. While the amplitude depends on the lower redshift cutoff, the direction is quite stable. For...
