Axion-like fields coupled to the Nieh-Yan term generate a chiral GW background during radiation domination, with parameter space explored for detectability in PTA and space-based observatories.
Gravitational waves from binary supermassive black holes missing in pulsar observations
9 Pith papers cite this work. Polarity classification is still indexing.
9
Pith papers citing it
abstract
Gravitational waves are expected to be radiated by supermassive black hole binaries formed during galaxy mergers. A stochastic superposition of gravitational waves from all such binary systems will modulate the arrival times of pulses from radio pulsars. Using observations of millisecond pulsars obtained with the Parkes radio telescope, we constrain the characteristic amplitude of this background, $A_{\rm c,yr}$, to be < $1.0\times10^{-15}$ with 95% confidence. This limit excludes predicted ranges for $A_{\rm c,yr}$ from current models with 91-99.7% probability. We conclude that binary evolution is either stalled or dramatically accelerated by galactic-center environments, and that higher-cadence and shorter-wavelength observations would result in an increased sensitivity to gravitational waves.
citation-role summary
dataset 2
citation-polarity summary
verdicts
UNVERDICTED 9roles
dataset 2polarities
use dataset 2representative citing papers
Defines peak-integrated sensitivity curves (PISCs) that fold in the expected spectral shape of gravitational waves from cosmological phase transitions and supplies semianalytical fits plus public data for major detectors.
Morphology-dependent M_bh-σ0 relations are reported: shallow (2.5-3.1) for dust-poor S0 galaxies and steep (7.8) for massive ellipticals, using new SCOPE Bayesian regression on 137 galaxies.
Finite-duration domain-wall nucleation during inflation produces a curvature power spectrum peaked at nanohertz frequencies whose scalar-induced gravitational waves match NANOGrav and EPTA data in a two-field model.
3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.
Establishes a model-independent link between scalar-induced GW backgrounds and PBH binary merger signals, including the mass-independent relation f_peak = 1.79 f_ISCO.
Kaniadakis entropic cosmology modifies early-universe dynamics and is constrained by its predictions for Starobinsky inflation and the primordial tensor spectrum using current CMB and gravitational-wave observations.
F-term hybrid inflation with SU(1,1)/U(1) or SU(2)/U(1) Kähler geometry in GUTs can be realized without inflationary extrema for broad parameters, matching ACT/SPT data via curvature and tadpole adjustments while predicting cosmic string gravitational waves.
A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.
citing papers explorer
-
Chiral Gravitational Wave Background from Audible Axion via Nieh-Yan Term
Axion-like fields coupled to the Nieh-Yan term generate a chiral GW background during radiation domination, with parameter space explored for detectability in PTA and space-based observatories.
-
New Sensitivity Curves for Gravitational-Wave Signals from Cosmological Phase Transitions
Defines peak-integrated sensitivity curves (PISCs) that fold in the expected spectral shape of gravitational waves from cosmological phase transitions and supplies semianalytical fits plus public data for major detectors.
-
Galaxy morphology dependent (black hole mass)-(velocity dispersion) relations: implications for gravitational wave forecasts and cosmological simulations
Morphology-dependent M_bh-σ0 relations are reported: shallow (2.5-3.1) for dust-poor S0 galaxies and steep (7.8) for massive ellipticals, using new SCOPE Bayesian regression on 137 galaxies.
-
Nanohertz gravitational waves from domain walls nucleated during inflation
Finite-duration domain-wall nucleation during inflation produces a curvature power spectrum peaked at nanohertz frequencies whose scalar-induced gravitational waves match NANOGrav and EPTA data in a two-field model.
-
Numerical simulations of density perturbation and gravitational wave production from cosmological first-order phase transition
3D simulations of cosmological first-order phase transitions find density perturbation spectra with k^3 and k^{-1.5} slopes and GW spectra with k^3 and k^{-2}, confirming slow transitions can produce PBHs.
-
Gravitational Waves from Primordial Black Holes: Connecting Low-Frequency Scalar-Induced Signatures to High-Frequency Binary Mergers
Establishes a model-independent link between scalar-induced GW backgrounds and PBH binary merger signals, including the mass-independent relation f_peak = 1.79 f_ISCO.
-
Constraints on Kaniadakis Cosmology from Starobinsky Inflation and Primordial Tensor Perturbations
Kaniadakis entropic cosmology modifies early-universe dynamics and is constrained by its predictions for Starobinsky inflation and the primordial tensor spectrum using current CMB and gravitational-wave observations.
-
F-Term Hybrid Inflation with T-Model K\"ahler Geometry and Beyond
F-term hybrid inflation with SU(1,1)/U(1) or SU(2)/U(1) Kähler geometry in GUTs can be realized without inflationary extrema for broad parameters, matching ACT/SPT data via curvature and tadpole adjustments while predicting cosmic string gravitational waves.
-
Scalar induced gravitational waves review
A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.