iTHEMS Cosmology Forum n°1 - Cosmic birefringence and Parity Violation in the universe

Contribution List

3. Tests for primordial parity symmetry - Observation Talk

Maresuke Shiraishi

14/05/2024, 10:30

Recent measurements of the CMB EB correlation and the imaginary galaxy trispectrum imply some parity-violating signals. These may originate from not only late-time axion phenomenology but also primordial one. Here, I would focus on the latter possibility, and talk about new findings and constraints on inflationary axion models from the above measurements, after reviewing primordial parity...

2. Cosmic birefringence tomography - Keynote Talk

Toshiya Namikawa (IPMU)

14/05/2024, 13:00

Cosmic birefringence --- a rotation of the linear polarization plane of the cosmic microwave background (CMB) as they travel through space --- is a key observational effect on CMB as it provides a way to search for parity-violating physics in cosmology. Recent measurements of the cross-correlation between the even-parity E-modes and odd-parity B-modes in the Planck polarization map suggest a...

4. Isotropic and anisotropic cosmic birefringence by axion domain walls - Theory Talk

Fuminobu Takahashi

14/05/2024, 15:30

The isotropic cosmic birefringence with a rotation angle of about 0.3 degrees has been suggested by the recent analysis of the CMB polarization data. The suggested rotation angle is tantalizingly close to the angle determined by the fine structure constant, 1/137 radians = 0.42 degrees. I will show that axion domain walls coupled to QED can naturally explain this coincidence for a wide range...

1. Opening remarks and coffee