Tensor-induced non-Gaussianity from primordial gravitational waves generates a unique scale-dependent halo bias correction that can reach order-one amplitude for rare high-redshift halos at z=7.
hub
The Quest for B Modes from Inflationary Gravitational Waves
13 Pith papers cite this work. Polarity classification is still indexing.
abstract
The search for the curl component (B mode) in the cosmic microwave background (CMB) polarization induced by inflationary gravitational waves is described. The canonical single-field slow-roll model of inflation is presented, and we explain the quantum production of primordial density perturbations and gravitational waves. It is shown how these gravitational waves then give rise to polarization in the CMB. We then describe the geometric decomposition of the CMB polarization pattern into a curl-free component (E mode) and curl component (B mode) and show explicitly that gravitational waves induce B modes. We discuss the B modes induced by gravitational lensing and by Galactic foregrounds and show how both are distinguished from those induced by inflationary gravitational waves. Issues involved in the experimental pursuit of these B modes are described, and we summarize some of the strategies being pursued. We close with a brief discussion of some other avenues toward detecting/characterizing the inflationary gravitational-wave background.
hub tools
citation-role summary
citation-polarity summary
roles
background 2polarities
background 2representative citing papers
Starobinsky inflation rules out two of three non-Gaussian fixed points in asymptotically safe scalar-tensor theories, identifying viable RG trajectories from the remaining fixed point.
Proposes that axion-photon conversion in pre-CMB helical magnetic fields imprints detectable V-mode polarization in the CMB, allowing CLASS 40 GHz observations to constrain ALP masses 10^{-10} to 10^{-8} eV and their photon coupling under optimistic nG field assumptions.
γ-duality in the EPRL spinfoam model determines the relation between parity-even and parity-odd terms in an effective gravity theory, allowing the Barbero-Immirzi parameter to be measured from inflationary tensor observables.
First CMB lensing reconstruction from two years of SPT-3G Summer temperature data yields A_comb = 1.015 ± 0.053 over 50 < L < 2000, consistent with Planck 2018 ΛCDM.
Adiabatic regularization combined with smoothed transitions suppresses the high-frequency oscillations in the power spectrum of primary gravitational waves about a zero mean.
Derives gauge-invariant perturbation equations for F(T, T_G) cosmology and provides physical interpretations for new contributions in each mode.
Phase transitions in dark sectors can generate CMB B-modes with amplitudes competitive with inflation but peaking at smaller angular scales.
A transient parity-violating phase during inflation generates a robust blue-tilted (n_T ≃ 2) primordial gravitational wave spectrum at small scales with nearly maximal helicity coherence and linear polarization, offering a cosmological template for PTA data distinct from astrophysical sources.
MHD shocks flatten the EE/BB ratio of polarized ISM emission to values ≳1 as energy injection increases, accompanied by a -7/2 power-law tail in velocity divergence.
The authors produce a new all-sky Galactic emission model with synchrotron amplitude at 4.76 GHz roughly twice the Planck 2015 value, derived via Commander fitting to recent radio and microwave surveys.
Reexamination of Planck CMB data finds a possible spatial-parity-breaking signal consistent with six extra dimensions compactified toroidally at the GUT scale before inflation.
A new 296-detector 90 GHz TES bolometer array for CLASS achieves uniform properties, 16 μK√s NET, 0.37 optical efficiency, and a 41% mapping speed boost after addressing blue-leak radiation.
citing papers explorer
-
Tracing Primordial Gravitational Waves via non-Gaussian Signatures of Halo Bias
Tensor-induced non-Gaussianity from primordial gravitational waves generates a unique scale-dependent halo bias correction that can reach order-one amplitude for rare high-redshift halos at z=7.
-
Starobinsky-inflation in asymptotically safe shift-symmetric scalar-tensor theory
Starobinsky inflation rules out two of three non-Gaussian fixed points in asymptotically safe scalar-tensor theories, identifying viable RG trajectories from the remaining fixed point.
-
Probing Axion-Photon conversion via circular polarization imprints in the CMB $V$-mode observations
Proposes that axion-photon conversion in pre-CMB helical magnetic fields imprints detectable V-mode polarization in the CMB, allowing CLASS 40 GHz observations to constrain ALP masses 10^{-10} to 10^{-8} eV and their photon coupling under optimistic nG field assumptions.
-
Spinfoams, $\gamma$-duality and parity violation in primordial gravitational waves
γ-duality in the EPRL spinfoam model determines the relation between parity-even and parity-odd terms in an effective gravity theory, allowing the Barbero-Immirzi parameter to be measured from inflationary tensor observables.
-
CMB Lensing Reconstruction Using Two Years of Temperature Data from the SPT-3G Summer Survey
First CMB lensing reconstruction from two years of SPT-3G Summer temperature data yields A_comb = 1.015 ± 0.053 over 50 < L < 2000, consistent with Planck 2018 ΛCDM.
-
Primary gravitational waves at high frequencies I: Origin of suppression in the power spectrum
Adiabatic regularization combined with smoothed transitions suppresses the high-frequency oscillations in the power spectrum of primary gravitational waves about a zero mean.
-
Gauge invariant perturbations of $F(T,T_G)$ Cosmology
Derives gauge-invariant perturbation equations for F(T, T_G) cosmology and provides physical interpretations for new contributions in each mode.
-
Observable CMB B-modes from Cosmological Phase Transitions
Phase transitions in dark sectors can generate CMB B-modes with amplitudes competitive with inflation but peaking at smaller angular scales.
-
Transient Parity Violation during Inflation: Implications for PTA Gravitational Waves
A transient parity-violating phase during inflation generates a robust blue-tilted (n_T ≃ 2) primordial gravitational wave spectrum at small scales with nearly maximal helicity coherence and linear polarization, offering a cosmological template for PTA data distinct from astrophysical sources.
-
The Shocking Origin of the Flat $EE/BB$ Ratio
MHD shocks flatten the EE/BB ratio of polarized ISM emission to values ≳1 as energy injection increases, accompanied by a -7/2 power-law tail in velocity divergence.
-
All-sky modeling of Galactic emission at radio and microwave frequencies
The authors produce a new all-sky Galactic emission model with synchrotron amplitude at 4.76 GHz roughly twice the Planck 2015 value, derived via Commander fitting to recent radio and microwave surveys.
-
Probing String-Theory-Inspired Topologies of the Early Universe through CMB Temperature and Polarization Anisotropies
Reexamination of Planck CMB data finds a possible spatial-parity-breaking signal consistent with six extra dimensions compactified toroidally at the GUT scale before inflation.
-
Detectors for CLASS-W2: The second 90 GHz telescope of the Cosmology Large Angular Scale Surveyor
A new 296-detector 90 GHz TES bolometer array for CLASS achieves uniform properties, 16 μK√s NET, 0.37 optical efficiency, and a 41% mapping speed boost after addressing blue-leak radiation.