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Features of heavy physics in the CMB power spectrum

10 Pith papers cite this work. Polarity classification is still indexing.

10 Pith papers citing it
abstract

The computation of the primordial power spectrum in multi-field inflation models requires us to correctly account for all relevant interactions between adiabatic and non-adiabatic modes around and after horizon crossing. One specific complication arises from derivative interactions induced by the curvilinear trajectory of the inflaton in a multi-dimensional field space. In this work we compute the power spectrum in general multi-field models and show that certain inflaton trajectories may lead to observationally significant imprints of `heavy' physics in the primordial power spectrum if the inflaton trajectory turns, that is, traverses a bend, sufficiently fast (without interrupting slow roll), even in cases where the normal modes have masses approaching the cutoff of our theory. We emphasise that turning is defined with respect to the geodesics of the sigma model metric, irrespective of whether this is canonical or non-trivial. The imprints generically take the form of damped superimposed oscillations on the power spectrum. In the particular case of two-field models, if one of the fields is sufficiently massive compared to the scale of inflation, we are able to compute an effective low energy theory for the adiabatic mode encapsulating certain relevant operators of the full multi-field dynamics. As expected, a particular characteristic of this effective theory is a modified speed of sound for the adiabatic mode which is a functional of the background inflaton trajectory and the turns traversed during inflation. Hence in addition, we expect non-Gaussian signatures directly related to the features imprinted in the power spectrum.

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representative citing papers

The UV Sensitivity of Axion Monodromy Inflation

hep-th · 2024-12-07 · unverdicted · novelty 6.0

In a string-inspired two-field axion monodromy model, oscillatory modulations excite heavy moduli during inflation, producing detectable cosmological collider signals in the primordial bispectrum that bypass Boltzmann suppression.

Orbital Inflation: inflating along an angular isometry of field space

hep-th · 2019-07-03 · unverdicted · novelty 6.0

Orbital Inflation reconstructs two-field actions with an angular isometry yielding single-field-like predictions that violate consistency relations and allow f_NL from slow-roll suppressed to O(few) depending on entropy mass and self-interactions.

Massive Exchange and the Sign of the Equilateral Bispectrum

hep-th · 2026-04-07 · unverdicted · novelty 6.0

The equilateral bispectrum from massive scalar exchange in inflation is not universally negative in the full EFT of inflation; its sign depends on a critical ratio of operator coefficients.

Inflation with vector fields revisited: non-Gaussianities

hep-th · 2026-05-27 · unverdicted · novelty 5.0

In kinetically coupled vector inflation, the bispectrum in the large-h regime exhibits competing local and flattened non-Gaussian signals with distinct h scalings that distinguish vector-supported dynamics.

A Compact Story of Positivity in de Sitter

hep-th · 2025-08-11 · unverdicted · novelty 5.0

Compares two methods to resolve disagreements and prove positivity of anomalous dimensions for principal series fields coupled to compact scalar operators in de Sitter space.

Primordial power spectrum reconstructions from BOSS + eBOSS

astro-ph.CO · 2026-05-18 · conditional · novelty 4.0

Non-parametric knot-based reconstruction of the primordial power spectrum P_R(k) from BOSS+eBOSS data up to k=0.3 h/Mpc favors a quasi-scale-invariant power law and constrains n_s = 0.976 ± 0.021 with no evidence for primordial features.

Scalar induced gravitational waves review

gr-qc · 2021-09-03 · unverdicted · novelty 2.0

A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.

citing papers explorer

Showing 10 of 10 citing papers.

  • Probing the small-scale primordial power spectrum via relic neutrinos and acoustic reheating hep-ph · 2026-05-12 · unverdicted · none · ref 11

    Dissipation of small-scale primordial perturbations after neutrino decoupling cools relic neutrinos and reduces their abundance, enabling PTOLEMY to constrain the primordial curvature power spectrum to O(0.1) on scales k ≲ 3×10^5 Mpc^{-1}.

  • The UV Sensitivity of Axion Monodromy Inflation hep-th · 2024-12-07 · unverdicted · none · ref 6 · internal anchor

    In a string-inspired two-field axion monodromy model, oscillatory modulations excite heavy moduli during inflation, producing detectable cosmological collider signals in the primordial bispectrum that bypass Boltzmann suppression.

  • Orbital Inflation: inflating along an angular isometry of field space hep-th · 2019-07-03 · unverdicted · none · ref 55 · internal anchor

    Orbital Inflation reconstructs two-field actions with an angular isometry yielding single-field-like predictions that violate consistency relations and allow f_NL from slow-roll suppressed to O(few) depending on entropy mass and self-interactions.

  • Massive Exchange and the Sign of the Equilateral Bispectrum hep-th · 2026-04-07 · unverdicted · none · ref 59

    The equilateral bispectrum from massive scalar exchange in inflation is not universally negative in the full EFT of inflation; its sign depends on a critical ratio of operator coefficients.

  • Inflation with vector fields revisited: non-Gaussianities hep-th · 2026-05-27 · unverdicted · none · ref 31 · internal anchor

    In kinetically coupled vector inflation, the bispectrum in the large-h regime exhibits competing local and flattened non-Gaussian signals with distinct h scalings that distinguish vector-supported dynamics.

  • A Compact Story of Positivity in de Sitter hep-th · 2025-08-11 · unverdicted · none · ref 7 · internal anchor

    Compares two methods to resolve disagreements and prove positivity of anomalous dimensions for principal series fields coupled to compact scalar operators in de Sitter space.

  • Signals from the early Universe: a comprehensive search for primordial features in Planck CMB datasets astro-ph.CO · 2026-05-28 · unverdicted · none · ref 23 · internal anchor

    Systematic re-analysis of Planck PR3 and PR4 CMB datasets finds local fit improvements of up to Δχ² ≈ -15 for certain oscillatory templates but no global significance above 2.6σ after look-elsewhere correction and Bayesian penalties.

  • Primordial power spectrum reconstructions from BOSS + eBOSS astro-ph.CO · 2026-05-18 · conditional · none · ref 18 · internal anchor

    Non-parametric knot-based reconstruction of the primordial power spectrum P_R(k) from BOSS+eBOSS data up to k=0.3 h/Mpc favors a quasi-scale-invariant power law and constrains n_s = 0.976 ± 0.021 with no evidence for primordial features.

  • CMB-S4 Science Case, Reference Design, and Project Plan astro-ph.IM · 2019-07-10 · unverdicted · none · ref 102 · internal anchor

    Presents the science case, reference design, and project plan for the CMB-S4 ground-based CMB experiment.

  • Scalar induced gravitational waves review gr-qc · 2021-09-03 · unverdicted · none · ref 269 · internal anchor

    A review that unifies analytical expressions for scalar-induced gravitational waves and emphasizes calculations for non-radiation-dominated cosmologies.