Related papers: Limits on high-frequency gravitational wave backgr…
While large scale cosmic microwave background (CMB) anisotropies involve a combination of the scalar and tensor fluctuations, the scalar amplitude can be independently determined through the CMB-galaxy cross-correlation. Using recently…
We study conversion processes between gravitons and dark photons and reveal the effects of dark photons on the polarization of gravitational waves. Considering cosmological dark magnetic fields, we investigate the evolution of the intensity…
We propose that there may be a substantial stochastic gravitational wave background from particle origin, mainly from the gravitational three-body decay of the inflaton. The emitted gravitons could constitute a sizable contribution to dark…
A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It is expected to carry unique signatures from the…
Primordial magnetic fields will generate non-Gaussian signals in the cosmic microwave background (CMB) as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. We compute a new measure of…
We show that a direct coupling between a chameleon-like scalar field and photons can give rise to a modified Sunyaev-Zel'dovich (SZ) effect in the Cosmic Microwave Background (CMB). The coupling induces a mixing between chameleon particles…
Spatially varying primordial magnetic fields may be efficiently dissipated prior to the epoch of recombination due to the large viscosity of the baryon-photon fluid. We show that this dissipation may result in observable chemical potential…
We study the propagation of cosmological gravitational wave (GW) backgrounds from the early radiation era until the present day in modified theories of gravity. Comparing to general relativity (GR), we study the effects that modified…
It is well known that energy fluxes will produce gravitational wave memory. The gravitational wave memory produced by background including cosmic microwave background (CMB), cosmic neutrino background (C$\nu$B), and gravitational wave…
Dark gauge fields have been discussed as candidates for dark matter recently. If they existed, primordial dark magnetic fields during inflation would have existed. It is believed that primordial gravitational waves (PGWs) arise out of…
We discuss the conversion mechanism from scalar field to gravitational waves in magnetic background in $f(R)$ gravity minimal coupled to the Maxwell electrodynamics. Applying the conversion in early universe with primordial magnetic field…
The transformation of powerful gravitational waves, created by the coalescence of massive black hole binaries, into electromagnetic radiation in external magnetic fields is revisited. In contrast to the previous calculations of the similar…
The magneto-hydrodynamic decay of primordial magnetic fields can distort the black-body spectrum of the cosmic microwave background (CMB) by draining magnetic energy into thermal plasmas and photons. The current limits on CMB distortion…
We investigate the possibility that a heavy scalar field, whose mass exceeds the Hubble scale during inflation, could leave non-negligible signatures in the Cosmic Microwave Background (CMB) temperature anisotropy power spectrum through the…
The next generation of instruments designed to measure the polarization of the cosmic microwave background (CMB) will provide a historic opportunity to open the gravitational wave window to the primordial Universe. Through high sensitivity…
The origin of large-scale magnetic fields is an unsolved problem in cosmology. In order to overcome, a possible scenario comes from the idea that these fields emerged from a small primordial magnetic field (PMF), produced in the early…
See comments. We calculate analytically an effect of the thermal Comptonization on the cosmic microwave background (CMB) photons when they propagate through galaxy clusters. We estimate a deformation of the CMB spectrum due to multiple…
Gravitational wave (GW) observations probe both a diffuse, stochastic gravitational wave background (SGWB) as well as individual cataclysmic events such as the merger of two compact objects. The detection and description of the…
High frequency gravitational waves are the subject of rapidly growing interest in the theoretical and experimental community. In this work we calculate the resonant conversion of gravitational waves into photons in the magnetospheres of…
We investigate the effects of the background primordial magnetic field (PMF) on the cosmic microwave background (CMB). The sound speed of the tightly coupled photon-baryon fluid is increased by the background PMF. The increased sound speed…