Abstract The Laser Interferometer Space Antenna (LISA) has two scientific objectives of
cosmological focus: to probe the expansion rate of the universe, and to understand …

Abstract LiteBIRD, the Lite (Light) satellite for the study of B-mode polarization and Inflation
from cosmic background Radiation Detection, is a space mission for primordial cosmology …

The current cosmological model requires new physics beyond the standard model of
elementary particles and fields, such as dark matter and dark energy. Their nature is …

We search for evidence of parity-violating physics in the Planck 2018 polarization data and
report on a new measurement of the cosmic birefringence angle β. The previous …

Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark
discovery, potentially providing a significant clue to some of our most basic, big-picture …

We demonstrate that the recently announced signal for a stochastic gravitational wave
background (SGWB) from pulsar timing array (PTA) observations, if attributed to new …

Although cosmic microwave background and large scale structure probe the largest scales
of our Universe with ever-increasing precision, our knowledge about the smaller scales is …

We present new constraints on the frequency dependence of the cosmic birefringence angle
from the Planck Data Release 4 polarization maps. An axion field coupled to …

Various scenarios of cosmic inflation enhance the amplitude of the stochastic gravitational
wave background (SGWB) at frequencies detectable by the LISA detector. We develop tools …

This paper explores the physics of second-order gravitational waves (GWs) induced by
scalar-tensor perturbation interactions in the radiation-dominated Universe. We investigate …