Introduces spectral dispersion bootstrap combining dS spectral decomposition and dispersion relations to compute 3- and 4-point loop correlators with massive scalar and vector exchanges.
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Acoustic Signatures in the Primary Microwave Background Bispectrum
13 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
If the primordial fluctuations are non-Gaussian, then this non-Gaussianity will be apparent in the cosmic microwave background (CMB) sky. With their sensitive all-sky observation, MAP and Planck satellites should be able to detect weak non-Gaussianity in the CMB sky. On large angular scale, there is a simple relationship between the CMB temperature and the primordial curvature perturbation. On smaller scales; however, the radiation transfer function becomes more complex. In this paper, we present the angular bispectrum of the primary CMB anisotropy that uses the full transfer function. We find that the bispectrum has a series of acoustic peaks that change a sign, and a period of acoustic oscillations is twice as long as that of the angular power spectrum. Using a single non-linear coupling parameter to characterize the amplitude of the bispectrum, we estimate the expected signal-to-noise ratio for COBE, MAP, and Planck experiments. We find that the detection of the primary bispectrum by any kind of experiments should be problematic for the simple slow-roll inflationary scenarios. We compare the sensitivity of the primary bispectrum to the primary skewness and conclude that when we can compute the predicted form of the bispectrum, it becomes a ``matched filter'' for detecting the non-Gaussianity in the data, and much more powerful tool than the skewness. We also show that MAP and Planck can separate the primary bispectrum from various secondary bispectra on the basis of the shape difference. The primary CMB bispectrum is a test of the inflationary scenario, and also a probe of the non-linear physics in the very early universe.
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representative citing papers
New SMICA formalism and binned bispectrum estimator jointly recover power spectra, spectral parameters, foreground 3-point correlators, and primordial non-Gaussianity constraints from multi-frequency polarization maps tested on LiteBIRD simulations.
Lattice simulations directly calculate SIGW spectra with non-Gaussianity to all orders and show that modest non-Gaussianity alters ultraviolet spectral behavior.
Neglecting linear GR effects biases f_NL at 1–3σ for Euclid/SPHEREx in SFB forecasts; multi-tracer improves Doppler detection and weakly breaks b_ϕ f_NL degeneracy.
Extends diagrammatic approach for scalar-induced gravitational waves to arbitrary-order local PNG, deriving semi-analytic spectra for energy density, anisotropies, bispectrum and trispectrum up to quartic terms.
Covariant analysis of curvature perturbations from first-order phase transitions reveals gauge-dependent overestimation of primordial black holes and gravitational waves in prior non-covariant calculations, leading to strong suppression of both signals.
Cross-correlation of DESI DR1 quasars with Planck PR4 CMB lensing constrains local f_NL to 2^{+28}_{-34} (p=1.6) or 6^{+20}_{-24} (p=1.0), tightening previous limits by 35%.
Curvaton coupling relaxes initial tuning in hilltop inflation and revives the sub-Planckian quartic model while remaining consistent with cosmological observations.
A spectator scalar in modulated reheating with large Higgs-like couplings generates detectable scalar-induced stochastic gravitational waves for BBO and DECIGO, but only outside perturbative low-energy extrapolations.
Constructs a (D_τ,D_x)-manifold with N-correlators of N_t-objects using field theory, topology, algebra, statistics and Fourier transforms, and discusses applicability across cosmological scales.
Dust-cleaned CIB and CMB lensing cross-correlations yield f_NL^local = 43 ± 23, tightening constraints on local primordial non-Gaussianity.
Updated SKAO-AA4 forecasts show multi-tracer HI+galaxy analyses can reach σ(f_local_NL)≲1 and improve αs bounds by tens of percent when combined with future CMB, while foregrounds and GR light-cone effects remain the main systematics.
A tutorial deriving cosmological perturbation equations from inflation through reheating, with explicit gauge-invariant computations and Python scripts.
citing papers explorer
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On-Shell Bootstrap of Loop Inflation Correlators with Spectral Dispersion
Introduces spectral dispersion bootstrap combining dS spectral decomposition and dispersion relations to compute 3- and 4-point loop correlators with massive scalar and vector exchanges.
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Non-Gaussianity in SMICA
New SMICA formalism and binned bispectrum estimator jointly recover power spectra, spectral parameters, foreground 3-point correlators, and primordial non-Gaussianity constraints from multi-frequency polarization maps tested on LiteBIRD simulations.
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Scalar-induced gravitational waves with non-Gaussianity up to all orders
Lattice simulations directly calculate SIGW spectra with non-Gaussianity to all orders and show that modest non-Gaussianity alters ultraviolet spectral behavior.
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Impact and measurability of linear relativistic effects in galaxy surveys
Neglecting linear GR effects biases f_NL at 1–3σ for Euclid/SPHEREx in SFB forecasts; multi-tracer improves Doppler detection and weakly breaks b_ϕ f_NL degeneracy.
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Isotropy, anisotropies and non-Gaussianity in the scalar-induced gravitational-wave background: diagrammatic approach for primordial non-Gaussianity up to arbitrary order
Extends diagrammatic approach for scalar-induced gravitational waves to arbitrary-order local PNG, deriving semi-analytic spectra for energy density, anisotropies, bispectrum and trispectrum up to quartic terms.
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Curvature Perturbations from First-Order Phase Transitions: Implications to Black Holes and Gravitational Waves
Covariant analysis of curvature perturbations from first-order phase transitions reveals gauge-dependent overestimation of primordial black holes and gravitational waves in prior non-covariant calculations, leading to strong suppression of both signals.
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Constraining primordial non-Gaussianity from DESI DR1 quasars and Planck PR4 CMB Lensing
Cross-correlation of DESI DR1 quasars with Planck PR4 CMB lensing constrains local f_NL to 2^{+28}_{-34} (p=1.6) or 6^{+20}_{-24} (p=1.0), tightening previous limits by 35%.
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Curvaton-assisted hilltop inflation
Curvaton coupling relaxes initial tuning in hilltop inflation and revives the sub-Planckian quartic model while remaining consistent with cosmological observations.
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Stochastic Gravitational Waves from Modulated Reheating
A spectator scalar in modulated reheating with large Higgs-like couplings generates detectable scalar-induced stochastic gravitational waves for BBO and DECIGO, but only outside perturbative low-energy extrapolations.
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A $(D_\tau,D_x)$-manifold with $N$-correlators of $N_t$-objects
Constructs a (D_τ,D_x)-manifold with N-correlators of N_t-objects using field theory, topology, algebra, statistics and Fourier transforms, and discusses applicability across cosmological scales.
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New constraints on primordial non-Gaussianity from large-scale cross-correlations of CMB lensing and the cosmic infrared background
Dust-cleaned CIB and CMB lensing cross-correlations yield f_NL^local = 43 ± 23, tightening constraints on local primordial non-Gaussianity.
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Beyond {\Lambda}CDM with the SKA Observatory -- II: Unveiling the Secrets of the Early Universe
Updated SKAO-AA4 forecasts show multi-tracer HI+galaxy analyses can reach σ(f_local_NL)≲1 and improve αs bounds by tens of percent when combined with future CMB, while foregrounds and GR light-cone effects remain the main systematics.
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From inflation to hot big bang -- a tutorial on cosmological perturbations
A tutorial deriving cosmological perturbation equations from inflation through reheating, with explicit gauge-invariant computations and Python scripts.