Pith. sign in

REVIEW 3 major objections 5 minor 176 references

Fitting the full two-field inflationary Lagrangian to Planck CMB bispectrum data, this paper finds no evidence for cosmological-collider particle exchange, with a maximum Δχ² of 5.3.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

T0 review · deepseek-v4-flash

2026-08-01 15:33 UTC pith:3OAQGBO7

load-bearing objection A careful null result that likely closes the simplest single-scalar collider in Planck, but the headline 'much tighter than theory' is prior-dependent and the squeezed-limit fits need validation. the 3 major comments →

arxiv 2607.18369 v1 pith:3OAQGBO7 submitted 2026-07-20 astro-ph.CO gr-qchep-exhep-phhep-th

Dissecting the Scalar Cosmological Collider with the Cosmic Microwave Background

classification astro-ph.CO gr-qchep-exhep-phhep-th
keywords cosmological colliderprimordial non-Gaussianitymulti-field inflationEFT of inflationCMB bispectrumPlanckstrong mixingscalar exchange
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper asks what current CMB data can actually say about heavy scalar particles during inflation, without assuming the coupling between that particle and the inflaton is small. It builds a complete tree-level bispectrum library for the two-field Lagrangian, covering single, double, and triple scalar exchange plus self-interactions, then jointly fits all eight parameters to measured CMB bispectrum shape data. The central result is a null: across the full mass, mixing, and sound-speed range, the best improvement over a no-signal model is Δχ² = 5.3, with no Bayesian evidence for new physics. A methodological corollary is that the previously assumed weak-mixing regime is observationally inaccessible — detectable signals require strong mixing, where the characteristic oscillatory 'collider' features are exponentially suppressed. A sympathetic reader would care because this closes off the simplest scalar cosmological-collider searches while quantifying where future, more sensitive data could land.

Core claim

On its own terms, the paper's central discovery is that the strongly-mixed cosmological collider — where the quadratic mixing between the Goldstone mode and a massive scalar is treated non-perturbatively — can now be confronted with data, and that Planck's measured bispectrum shape shows no sign of it. The author computes all seven tree-level bispectrum templates for the two-field EFT, parameterized by two sound-speeds, a scalar mass, a mixing coefficient, and four cubic couplings. Against the binned Planck shape measurements, no parameter combination produces a significant detection: maximum Δχ² of 5.3 over the null hypothesis and 3.3 over the single-field model, signal-to-noise never above

What carries the argument

The load-bearing object is the tree-level bispectrum shape function Sζ(x,y) of the curvature perturbation, assembled from a seven-term cubic Lagrangian whose amplitudes are partially fixed by non-linearly realized symmetries. In the weak-mixing limit, the exchange templates come from an analytic cosmological bootstrap, factorized in the couplings; for arbitrary mixing, the paper solves the time evolution numerically with a flow-based method, treating the quadratic π–σ mixing non-perturbatively. The computational simplification is that the likelihood is linear in the four cubic amplitudes, allowing analytic marginalization down to a four-dimensional space of quadratic parameters (sound-speeds

Load-bearing premise

The constraints rest on the numerical strong-mixing bispectrum templates being accurate in exactly the regimes that are hardest to compute — highly squeezed triangles (x<0.01, filled by analytic fits) and very large mixing (modeled through a non-local effective Lagrangian) — since those regimes set the reported bounds.

What would settle it

A direct numerical recomputation of the strong-mixing templates using an independent in-in solver that resolves squeezing down to x = 10⁻⁴, without analytic fitting, and re-evaluating the ρ-only likelihood near m ≈ H: if Δχ² moves substantially from 5.3 (say, below 2 or above 10), the paper's constraints would need revision. Observationally, a future CMB or 21-cm measurement with roughly five times better equilateral sensitivity that finds Δχ² > 10 at any fixed mass would falsify the paper's claim that no scalar collider signal is present in the allowed parameter space.

Watch this falsifier — get emailed when new claim-graph text bears on it.

If this is right

  • Weak-mixing cosmological-collider templates cannot be detected in current data: the coupling required for a visible signal violates perturbativity for most masses, so earlier template searches implicitly probed an inconsistent regime.
  • Strong-mixing analyses place the tightest data-driven bounds to date on the multi-field Lagrangian, with ρ ≲ 170H at 95% and the cubic exchange amplitudes bounded orders of magnitude below unitarity limits.
  • The oscillatory collider features are exponentially suppressed whenever the mixing is large enough to be theoretically allowed, meaning the same physics that could make the signal detectable also damps the oscillations.
  • No mass point in either the complementary or principal series shows detection above about 2σ, and Bayesian evidence disfavors the multi-field model against the null at all masses.
  • Future probes with improved equilateral-type sensitivity — for example, next-generation CMB or 21-cm observations — are needed to reach the strong-mixing region, since current data already sit at the theoretical edge.
  • Beyond the paper's claims: because the null persists under both linear and logarithmic priors on the mixing, the no-detection verdict is probably stable, but the headline bounds (ρ ≲ 170H versus ρ ≲ 50H) are prior-dependent and should not be over-interpreted.
  • The analytic marginalization over cubic amplitudes is a reusable technique: any bispectrum analysis whose model is linear in a subset of couplings can be reduced to a low-dimensional quadratic-parameter scan, which is what makes an eight-parameter likelihood feasible in milliseconds.
  • A testable extension: applying the same Lagrangian-level scan to the CMB trispectrum or to large-scale structure bispectra with a few-fold better sensitivity would either sharpen the ρ bound or begin resolving the suppressed oscillations, distinguishing a strict null from a faint signal.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. This paper performs a joint Bayesian analysis of the two-field inflationary effective field theory, coupling the Goldstone mode to a massive scalar. It builds a library of tree-level bispectrum templates: analytic self-interaction shapes, weak-mixing single-exchange shapes from the cosmological bootstrap, and strong-mixing shapes from the CosmoFlow numerical solver (supplemented by a non-local single-field Lagrangian at large mixing). These are compared to the binned Planck primordial bispectrum shape measurements of Ref. [44] using a likelihood with analytic marginalization over the cubic couplings, sampled with nested sampling and HMC. The main results are: no evidence for new physics across the full parameter space, with a maximum chi-squared improvement of 5.3; 95% bounds in the strong-mixing regime (rho less than about 170H under a flat prior, with bounds on Delta-rho, alpha, and mu); and a demonstration that weak-mixing templates require couplings in tension with perturbativity except at the smallest masses. The paper also reports that in the strong-mixing regime Planck constraints are much tighter than the theoretical unitarity bounds, although the oscillatory collider signatures are exponentially suppressed.

Significance. If the central claims hold, this is a substantial step forward for the cosmological collider program. It is, to my knowledge, the first analysis that treats the strongly-mixed scalar collider with CMB data, jointly constraining all four quadratic and four cubic operators rather than fitting a single f_NL template. The paper makes good use of public data and modern tools, and it contains genuine cross-checks: bootstrap versus CosmoFlow agreement at weak mixing, analytic self-interaction shapes, and two independent samplers. The central null result — no evidence for new physics — appears robust. The quantitative bounds on rho, Delta-rho, alpha, and mu are potentially useful and go beyond existing work, but they rest on numerical templates in a regime where some approximations are not fully validated.

major comments (3)
  1. [III A 2, p. 10] The strong-mixing templates are evaluated only for x >= 0.01; configurations with x < 0.01 are filled using analytic squeezed-limit fits to Eq. (16), anchored on x in [0.01, 0.1]. The Planck binned shape data extend to x = 10^{-3}. The paper's strong-mixing constraints (Fig. 8: rho less than about 170H, Delta-rho, alpha, mu bounds) and the quoted maximum Delta-chi^2 = 5.3 are computed from these filled templates. This is load-bearing because the leading x^{1/2 ± i mu} scaling and any collider oscillations live at exactly these small-x bins. The manuscript does not validate the extrapolation against direct CosmoFlow evaluations at x<0.01, nor does it report whether the constraints survive if the x<0.01 bins are simply excluded. I ask the authors to add such a validation (e.g. evaluate a subset of templates at x = 10^{-3} or show that dropping all x<0.01 bins leaves the quoted bounds and D
  2. [IV C / Appendix A] The headline constraints are strongly prior-dependent. With the flat prior on rho used in the main text, rho_95 is about 170H and the maximum signal-to-noise is about 2.0 sigma. Appendix A shows that a log-uniform prior on rho gives rho_95 about 50H and a maximum signal-to-noise of 0.6 sigma. The main text does mention this sensitivity, but the abstract's positive claim that 'Planck constraints are much tighter than the theoretical bounds' is stated without this caveat. Given the factor of three difference in the central bound and the reduction of the detection significance to below 1 sigma, the abstract and conclusions should state the prior choice explicitly and note that the quantitative bounds are prior-dependent.
  3. [III A 2 / Fig. 3] The paper's validation of the CosmoFlow pipeline is shown in Fig. 3 only for the (d_mu pi)^2 sigma channel. The text states that the other channels (pi-dot^2 sigma, self-interactions, and the non-local large-rho regime) were checked, but no quantitative comparison is shown. The strong-mixing likelihood uses all seven templates, and the non-local Lagrangian (17) is used for rho up to 10^3 H. Please provide a figure or table comparing local and non-local templates and bootstrap/analytic shapes at the overlap boundaries, or at least state the obtained agreement quantitatively. Without this, it is difficult to assess the systematic error in the reported bounds from template error.
minor comments (5)
  1. [Eq. (22)] The likelihood is written as log L(Theta_2, Theta_2) but should be log L(Theta_2, Theta_3).
  2. [Fig. 8 / Fig. 11] The axis labels for the Delta-rho panels show '2|Delta-rho|/H' while the text quotes '2 pi Delta_zeta |Delta-rho| less than about 150H'. Please make the normalization consistent.
  3. [Appendix A] The phrase 'Non-unitarty' appears in the figure; should be 'Non-unitary'.
  4. [References] The analysis depends on the companion paper [99] and the binned-shape data paper [44], both unpublished and by the same author. Please state clearly in the text which results are self-contained and which depend on these papers, and confirm that the data and code will be publicly released.
  5. [IV C] The maximum Delta-chi^2 of 5.3 is reported without an associated p-value or number of trials over the mass grid and analysis variants. The AIC/BIC statements are helpful, but a look-elsewhere-corrected significance would strengthen the null conclusion.

Circularity Check

0 steps flagged

No significant circularity: theory templates are computed from the Lagrangian and compared to external Planck bispectrum measurements; fπ calibration is a standard normalization that cancels in the shape.

full rationale

The paper's chain is: (i) write the two-field Lagrangian (Eq. 5) with quadratic and cubic couplings; (ii) compute tree-level bispectrum templates — analytically/bootstrap for weak mixing and numerically with CosmoFlow for strong mixing (Eq. 15); (iii) compare these templates with the binned Planck shape measurements of [44] via the likelihood (Eqs. 22-24); (iv) report no detection. The templates are theory outputs, not fits to the bispectrum data. The parameter fπ is calibrated to the observed power-spectrum amplitude (Sec. II B: "we define fπ using the best-fit Planck amplitude via 4π^2Δζ^2(fπ/H)^4 = ⟨πcπc⟩/⟨πcπc⟩ideal"), but this is a standard normalization that cancels in the dimensionless shape Sζ of Eq. (10), so it does not inject the target bispectrum into the model. Strong-mixing shapes are cross-validated against bootstrap results in the weak-mixing limit (Fig. 3) and against analytic self-interaction shapes, giving independent checks. The main self-citations are the binned shape dataset [44] and the companion weak-mixing study [99]; [44] is an external measurement of Planck maps rather than a theoretical input, and the weak-mixing incompatibility claim in [99] is also re-derived in this paper (Fig. 6). The filling of the squeezed x<0.01 region with analytic fits to Eq. (16) anchored to x∈[0.01,0.1] is an approximation to the theory templates, not a fit to the CMB data; it is a possible robustness limitation but does not make the prediction equal to an input. No step reduces by construction to a fitted parameter, a definitional identity, or a self-citation chain.}

Axiom & Free-Parameter Ledger

3 free parameters · 6 axioms · 0 invented entities

The model parameters are all standard EFT couplings; no new particles are invented. The main modeling choices are prior widths, grid boundaries, and the approximate unitarity formulas used as priors.

free parameters (3)
  • ρ prior choice (flat vs log) = 95% bound ρ≲170H (flat) vs ρ≲50H (log)
    Central strong-mixing constraints depend on the chosen prior on quadratic mixing; Appendix A shows order-of-magnitude changes in the reported bounds.
  • Gaussian prior widths on cubic couplings = σ = Δρ_max(Θ2), α_max(Θ2), μ_max(Θ2) from unitarity bounds (19)
    Posteriors for Δρ, α, ˜c3(cπ^{-2}-1) reproduce these priors in several mass ranges; they set the reported 'constraints' more than the data do.
  • mass grid points = m/H ∈ {0.2..5.2}; 15 complementary + 51 principal-series points
    m is fixed at discrete grid points rather than sampled; all reported bounds are evaluated only at those masses.
axioms (6)
  • domain assumption De Sitter limit with ns=1 for all shape computations
    All templates are computed in the dS limit (§III A), while the data are generated with a scale-dependent spectrum (ns=0.966); scale-dependence of shapes is neglected.
  • domain assumption Bunch-Davies initial vacuum for the numerical flow
    CosmoFlow is initialized from Bunch-Davies vacuum (§III A2); non-Bunch-Davies initial states would change the shapes and are outside the model.
  • domain assumption Tree-level bispectra; cubic interactions perturbative even for large quadratic mixing
    CosmoFlow treats the quadratic Lagrangian non-perturbatively but remains perturbative in cubic interactions (§III A2); loops and non-linear cubic resummations are ignored.
  • domain assumption The binned shape measurements of [44] are unbiased with correct covariance
    The likelihood (22) uses bSi and Cij from [44]; any bias in the estimator or covariance propagates directly into all constraints.
  • domain assumption Unitarity/perturbativity formulas (18)-(20) from [120] are sufficient as prior bounds
    These approximate bounds set the Gaussian priors for Δρ, α, μ in the strong-mixing analysis; their approximate nature could distort marginalized constraints.
  • domain assumption Non-linear realization of symmetries fixes λ, κ, β in terms of quadratic parameters
    Equation (5)-(6) fixes the coefficients of (∂π)²σ, (∂π)²∂π, and β via symmetry; this is a standard EFT-of-inflation assumption but not derived in this paper.

pith-pipeline@v1.3.0-alltime-deepseek · 29486 in / 11692 out tokens · 98601 ms · 2026-08-01T15:33:59.851050+00:00 · methodology

0 comments
read the original abstract

The cosmological collider program probes ultra-high-energy physics by searching for subtle oscillatory signatures induced by inflationary particle exchange. Due to the non-linear symmetries usually assumed in inflation, these signals do not appear in isolation; moreover, their amplitudes are bounded by perturbativity and unitarity. To comprehensively probe cosmological collider physics, we must jointly analyze the full multi-field inflationary Lagrangian: in this work, we conduct such a study, probing single, double, and triple scalar field exchange and self-interactions across a wide range of masses (in both the complementary and principal series), mixings, and sound-speeds. Using modern theoretical tools (including the cosmological bootstrap and the cosmological flow), we construct a vast library of tree-level primordial bispectra: combining these with recent measurements of the inflationary shape function from Planck and modern sampling techniques, we perform Bayesian exploration of the eight-parameter multi-field likelihood. Most previous studies of cosmological collider physics assume weak mixing, such that the coupling between the scalar field and the Goldstone mode can be treated perturbatively: in our companion study, we demonstrate that this assumption is incompatible with current datasets except at the smallest masses. By solving for the inflationary bispectra numerically using CosmoFlow, we perform the first analysis of the strongly-mixed collider, demonstrating that the Planck constraints are much tighter than the theoretical bounds, though the oscillatory contributions are heavily suppressed. Across the full multi-field landscape, we find no evidence for new physics with a maximal $\chi^2$ improvement of $5.3$.

Figures

Figures reproduced from arXiv: 2607.18369 by Oliver H. E. Philcox.

Figure 1
Figure 1. Figure 1: FIG. 1 [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2 [PITH_FULL_IMAGE:figures/full_fig_p008_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3 [PITH_FULL_IMAGE:figures/full_fig_p009_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4 [PITH_FULL_IMAGE:figures/full_fig_p010_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5 [PITH_FULL_IMAGE:figures/full_fig_p013_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: FIG. 6 [PITH_FULL_IMAGE:figures/full_fig_p014_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: FIG. 7 [PITH_FULL_IMAGE:figures/full_fig_p015_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: FIG. 8 [PITH_FULL_IMAGE:figures/full_fig_p017_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: FIG. 9 [PITH_FULL_IMAGE:figures/full_fig_p018_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: FIG. 10 [PITH_FULL_IMAGE:figures/full_fig_p019_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: FIG. 11 [PITH_FULL_IMAGE:figures/full_fig_p021_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: FIG. 12 [PITH_FULL_IMAGE:figures/full_fig_p022_12.png] view at source ↗

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

176 extracted references · 147 linked inside Pith

  1. [1]

    In this case, non-Gaussianity is generated by the two cubic self-interactions, ( ∂µπ)2 ˙πand ˙π3, with amplitudes set by λ and ∆λ

    No Mixing(ρ= 0) For ρ = 0, π and σ decouple, thus (5) reduces to the single-field EFT Lagrangian. In this case, non-Gaussianity is generated by the two cubic self-interactions, ( ∂µπ)2 ˙πand ˙π3, with amplitudes set by λ and ∆λ. Explicitly, the tree-level bispectrum is given by Sno ζ (x, y;cπ,˜c3) =λ(c π, cσ)S(λ) ζ (x, y;crel) + ∆λ(cπ, cσ,˜c3)S(∆λ) ζ (x, ...

  2. [2]

    Since the double- and triple exchange diagrams shown in Fig

    Weak Mixing(ρ≪H) Next, we allow for a small mixing of the Goldstone mode with the massive scalar, σ. Since the double- and triple exchange diagrams shown in Fig. 1 require additional ˙πσmixings (each of which is suppressed by ρ/H), we focus on the single exchange diagrams arising from ( ∂µπ)2σ and ˙π2σ, whose amplitudes scale as ρκ∝ρ 2 and ρ∆κ∝ρ ∆ρ respec...

  3. [3]

    1), each of which can be written in terms of a 6 We defineS (ρκ) ζ ≡∂S ζ /∂(ρκ) ρ=λ=∆λ=∆κ=0, working in theρ→0 limit

    Strong Mixing(ρ≳H) Finally, we consider the full tree-level bispectrum, incorporating all terms in the Lagrangian of (5) and allowing for arbitrary values of the mixing coefficient ρ.7 The combined bispectrum shape is the sum of two self-interactions, two single exchanges, two double exchanges and one triple exchange (see Fig. 1), each of which can be wri...

  4. [4]

    A. H. Guth, Phys. Rev. D23, 347 (1981)

  5. [5]

    A. A. Starobinsky, Phys. Lett. B91, 99 (1980)

  6. [6]

    A. D. Linde, Phys. Lett. B108, 389 (1982)

  7. [7]

    Albrecht and P

    A. Albrecht and P. J. Steinhardt, Phys. Rev. Lett.48, 1220 (1982)

  8. [8]

    V. F. Mukhanov and G. V. Chibisov, JETP Lett.33, 532 (1981)

  9. [9]

    A. A. Starobinsky, Phys. Lett. B117, 175 (1982)

  10. [10]

    Flauger, L

    R. Flauger, L. McAllister, E. Pajer, A. Westphal, and G. Xu, JCAP06, 009 (2010), arXiv:0907.2916 [hep-th]

  11. [11]

    Flauger and E

    R. Flauger and E. Pajer, JCAP01, 017 (2011), arXiv:1002.0833 [hep-th]

  12. [12]

    Adshead, C

    P. Adshead, C. Dvorkin, W. Hu, and E. A. Lim, Phys. Rev. D85, 023531 (2012), arXiv:1110.3050 [astro-ph.CO]

  13. [13]

    Ach´ ucarro, J.-O

    A. Ach´ ucarro, J.-O. Gong, G. A. Palma, and S. P. Patil, Phys. Rev. D87, 121301 (2013), arXiv:1211.5619 [astro-ph.CO]

  14. [14]

    Langlois, S

    D. Langlois, S. Renaux-Petel, D. A. Steer, and T. Tanaka, Phys. Rev. D78, 063523 (2008), arXiv:0806.0336 [hep-th]

  15. [15]

    Senatore and M

    L. Senatore and M. Zaldarriaga, JHEP04, 024 (2012), arXiv:1009.2093 [hep-th]

  16. [16]

    C. T. Byrnes and K.-Y. Choi, Adv. Astron.2010, 724525 (2010), arXiv:1002.3110 [astro-ph.CO]

  17. [17]

    Chen and Y

    X. Chen and Y. Wang, JCAP04, 027 (2010), arXiv:0911.3380 [hep-th]

  18. [18]

    Flauger, M

    R. Flauger, M. Mirbabayi, L. Senatore, and E. Silverstein, JCAP10, 058 (2017), arXiv:1606.00513 [hep-th]

  19. [19]

    C. M. Sou, X. Tong, and Y. Wang, JHEP06, 129 (2021), arXiv:2104.08772 [hep-th]

  20. [20]

    J. H. Kim, S. Kumar, A. Martin, and Y. Tsai, JHEP11, 158 (2021), arXiv:2107.09061 [hep-ph]

  21. [21]

    Barnaby and Z

    N. Barnaby and Z. Huang, Phys. Rev. D80, 126018 (2009), arXiv:0909.0751 [astro-ph.CO]

  22. [22]

    H. Lee, D. Baumann, and G. L. Pimentel, JHEP12, 040 (2016), arXiv:1607.03735 [hep-th]. 21 1 2 3 4 5 m/H 100 101 102 103 95% bound Weak Strong /H Free 1 2 3 4 5 m/H Weak Strong Non-unitarty 2 | /H| + free , , 1 2 3 4 5 m/H Weak Strong Non-unitarty | | + free c , c3 1 2 3 4 5 m/H Weak Strong Non-unitarty | /H| + free c 1 2 3 4 5 m/H -2 0 2 X/ (X) /H Free 1 ...

  23. [23]

    Cosmological Collider Physics,

    N. Arkani-Hamed and J. Maldacena, “Cosmological Collider Physics,” (2015), arXiv:1503.08043 [hep-th]

  24. [24]

    Berera, Phys

    A. Berera, Phys. Rev. Lett.75, 3218 (1995), arXiv:astro-ph/9509049

  25. [25]

    Lopez Nacir, R

    D. Lopez Nacir, R. A. Porto, L. Senatore, and M. Zaldarriaga, JHEP01, 075 (2012), arXiv:1109.4192 [hep-th]

  26. [26]

    S. A. Salcedo, T. Colas, and E. Pajer, JHEP10, 248 (2024), arXiv:2404.15416 [hep-th]

  27. [27]

    Chen, Adv

    X. Chen, Adv. Astron.2010, 638979 (2010), arXiv:1002.1416 [astro-ph.CO]

  28. [28]

    X. Chen, M. H. Namjoo, and Y. Wang, JCAP02, 013 (2016), arXiv:1509.03930 [astro-ph.CO]

  29. [29]

    J. M. Maldacena, JHEP05, 013 (2003), arXiv:astro-ph/0210603

  30. [30]

    Bartolo, E

    N. Bartolo, E. Komatsu, S. Matarrese, and A. Riotto, Phys. Rept.402, 103 (2004), arXiv:astro-ph/0406398

  31. [31]

    Komatsu, Class

    E. Komatsu, Class. Quant. Grav.27, 124010 (2010), arXiv:1003.6097 [astro-ph.CO]. 22 2 0 2 log10 0.8 0.6 0.4 0.2 log10 c 1.5 1.0 0.5 log10 c 2 0 2 c3(c 2 1) (scaled) 2 0 2 (scaled) 2 0 2 (scaled) 2 0 2 (scaled) 2 0 2 (scaled) 2 0 2 (scaled) 2 0 2 (scaled) 2 0 2 c3(c 2 1) (scaled) 1.5 1.0 0.5 log10 c 0.9 0.5 0.1 log10 c m = 0.2H m = 5.2H Prior FIG. 12.Joint...

  32. [32]

    Liguori, E

    M. Liguori, E. Sefusatti, J. R. Fergusson, and E. P. S. Shellard, Adv. Astron.2010, 980523 (2010), arXiv:1001.4707 [astro-ph.CO]

  33. [33]

    P. D. Meerburget al., Bull. Am. Astron. Soc.51, 107 (2019), arXiv:1903.04409 [astro-ph.CO]

  34. [34]

    A.et al., (2022), arXiv:2203.08128

    A. A.et al., (2022), arXiv:2203.08128

  35. [35]

    D. H. Lyth and D. Wands, Phys. Lett. B524, 5 (2002), arXiv:hep-ph/0110002

  36. [36]

    Dvali, A

    G. Dvali, A. Gruzinov, and M. Zaldarriaga, Phys. Rev. D69, 023505 (2004), arXiv:astro-ph/0303591

  37. [37]

    Bartolo, S

    N. Bartolo, S. Matarrese, and A. Riotto, Phys. Rev. D69, 043503 (2004), arXiv:hep-ph/0309033. 23

  38. [38]

    Sasaki, J

    M. Sasaki, J. Valiviita, and D. Wands, Phys. Rev. D74, 103003 (2006), arXiv:astro-ph/0607627

  39. [39]

    Suyama and M

    T. Suyama and M. Yamaguchi, Phys. Rev. D77, 023505 (2008), arXiv:0709.2545 [astro-ph]

  40. [40]

    Creminelli, A

    P. Creminelli, A. Nicolis, L. Senatore, M. Tegmark, and M. Zaldarriaga, JCAP05, 004 (2006), arXiv:astro-ph/0509029

  41. [41]

    Komatsu, D

    E. Komatsu, D. N. Spergel, and B. D. Wandelt, Astrophys. J.634, 14 (2005), arXiv:astro-ph/0305189

  42. [42]

    Senatore, K

    L. Senatore, K. M. Smith, and M. Zaldarriaga, JCAP01, 028 (2010), arXiv:0905.3746 [astro-ph.CO]

  43. [43]

    O. H. E. Philcox, Phys. Rev. D111, 123534 (2025), arXiv:2502.06931 [astro-ph.CO]

  44. [44]

    O. H. E. Philcox, S. Kumar, and J. C. Hill, Phys. Rev. D111, 103523 (2025), arXiv:2405.03738 [astro-ph.CO]

  45. [45]

    L. H. A. El-Haj, O. H. E. Philcox, and J. C. Hill, Phys. Rev. D113, 103518 (2026), arXiv:2509.23123 [astro-ph.CO]

  46. [46]

    Optimal Trispectrum Estimators and WMAP Constraints,

    J. R. Fergusson, D. M. Regan, and E. P. S. Shellard, “Optimal Trispectrum Estimators and WMAP Constraints,” (2010), arXiv:1012.6039 [astro-ph.CO]

  47. [47]

    O. H. E. Philcox, (2026), arXiv:2603.17004 [astro-ph.CO]

  48. [48]

    Planck Collaboration, P. A. R. Ade, N. Aghanim, C. Armitage-Caplan, M. Arnaud, M. Ashdown, F. Atrio-Barandela, J. Aumont, C. Baccigalupi, A. J. Banday,et al., A&A571, A24 (2014), arXiv:1303.5084 [astro-ph.CO]

  49. [49]

    P. A. R. Adeet al.(Planck), Astron. Astrophys.594, A17 (2016), arXiv:1502.01592 [astro-ph.CO]

  50. [50]

    Akramiet al.(Planck), Astron

    Y. Akramiet al.(Planck), Astron. Astrophys.641, A9 (2020), arXiv:1905.05697 [astro-ph.CO]

  51. [51]

    Sohn, D.-G

    W. Sohn, D.-G. Wang, J. R. Fergusson, and E. P. S. Shellard, JCAP09, 016 (2024), arXiv:2404.07203 [astro-ph.CO]

  52. [52]

    G. Jung, M. Citran, B. van Tent, L. Dumilly, and N. Aghanim, Astron. Astrophys.702, A204 (2025), arXiv:2504.00884 [astro-ph.CO]

  53. [53]

    Primordial non-Gaussianity constraints on dissipative inflation,

    S. A. Salcedo, T. Colas, P. Suman, B. Zhang, J. Fergusson, and E. P. S. Shellard, “Primordial non-Gaussianity constraints on dissipative inflation,” (2026), arXiv:2603.13473 [astro-ph.CO]

  54. [54]

    How Significant are Cosmological Collider Signals in the Planck Data?

    P. Suman, D.-G. Wang, W. Sohn, J. R. Fergusson, and E. P. S. Shellard, “How Significant are Cosmological Collider Signals in the Planck Data?” (2025), arXiv:2511.17500 [astro-ph.CO]

  55. [55]

    Searching for Cosmological Collider in the Planck CMB Data II: collider templates and Modal analysis,

    P. Suman, D.-G. Wang, W. Sohn, J. R. Fergusson, and E. P. S. Shellard, “Searching for Cosmological Collider in the Planck CMB Data II: collider templates and Modal analysis,” (2025), arXiv:2512.22085 [astro-ph.CO]

  56. [56]

    Cosmological Collider Searches beyond the Hubble Scale with Planck Data,

    S. Kumar, Q. Lu, Z.-Z. Xianyu, and Y. Zhang, “Cosmological Collider Searches beyond the Hubble Scale with Planck Data,” (2026), arXiv:2603.15728 [hep-ph]

  57. [57]

    Kumar, Q

    S. Kumar, Q. Lu, Z.-Z. Xianyu, and Y. Zhang, (2026), arXiv:2604.07434 [hep-ph]

  58. [58]

    O. H. E. Philcox, K. Zhong, and S. S. Sirletti, (2025), arXiv:2511.19179 [astro-ph.CO]

  59. [59]

    O. H. E. Philcox, G. L. Pimentel, and C. Yang, (2026), arXiv:2603.13486 [astro-ph.CO]

  60. [60]

    Cabass, M

    G. Cabass, M. M. Ivanov, O. H. E. Philcox, M. Simonovi´ c, and M. Zaldarriaga, Phys. Rev. Lett.129, 021301 (2022), arXiv:2201.07238 [astro-ph.CO]

  61. [61]

    Cabass, M

    G. Cabass, M. M. Ivanov, O. H. E. Philcox, M. Simonovi´ c, and M. Zaldarriaga, Phys. Rev. D106, 043506 (2022), arXiv:2204.01781 [astro-ph.CO]

  62. [62]

    D’Amico, M

    G. D’Amico, M. Lewandowski, L. Senatore, and P. Zhang, (2022), arXiv:2201.11518 [astro-ph.CO]

  63. [63]

    Green, Y

    D. Green, Y. Guo, J. Han, and B. Wallisch, JCAP05, 090 (2024), arXiv:2311.04882 [astro-ph.CO]

  64. [64]

    Cabass, O

    G. Cabass, O. H. E. Philcox, M. M. Ivanov, K. Akitsu, S.-F. Chen, M. Simonovi´ c, and M. Zaldarriaga, Phys. Rev. D111, 063510 (2025), arXiv:2404.01894 [astro-ph.CO]

  65. [65]

    Chudaykin, M

    A. Chudaykin, M. M. Ivanov, and O. H. E. Philcox, Phys. Rev. D113, 063552 (2026), arXiv:2512.04266 [astro-ph.CO]

  66. [66]

    Green, J

    D. Green, J. Han, and B. Wallisch, (2026), arXiv:2602.12232

  67. [67]

    Chaussidonet al., JCAP06, 029 (2025), arXiv:2411.17623 [astro-ph.CO]

    E. Chaussidonet al., JCAP06, 029 (2025), arXiv:2411.17623 [astro-ph.CO]

  68. [68]

    Cheung, P

    C. Cheung, P. Creminelli, A. L. Fitzpatrick, J. Kaplan, and L. Senatore, JHEP03, 014 (2008), arXiv:0709.0293 [hep-th]

  69. [69]

    Weinberg, Phys

    S. Weinberg, Phys. Rev. D77, 123541 (2008), arXiv:0804.4291 [hep-th]

  70. [70]

    Chen and Y

    X. Chen and Y. Wang, Phys. Rev. D81, 063511 (2010), arXiv:0909.0496 [astro-ph.CO]

  71. [71]

    Baumann and D

    D. Baumann and D. Green, Phys. Rev. D85, 103520 (2012), arXiv:1109.0292 [hep-th]

  72. [72]

    Assassi, D

    V. Assassi, D. Baumann, and D. Green, JCAP11, 047 (2012), arXiv:1204.4207 [hep-th]

  73. [73]

    Noumi, M

    T. Noumi, M. Yamaguchi, and D. Yokoyama, JHEP06, 051 (2013), arXiv:1211.1624 [hep-th]

  74. [74]

    Chen and Y

    X. Chen and Y. Wang, JCAP09, 021 (2012), arXiv:1205.0160 [hep-th]

  75. [75]

    Pi and M

    S. Pi and M. Sasaki, JCAP10, 051 (2012), arXiv:1205.0161 [hep-th]

  76. [76]

    Green, M

    D. Green, M. Lewandowski, L. Senatore, E. Silverstein, and M. Zaldarriaga, JHEP10, 171 (2013), arXiv:1301.2630 [hep-th]

  77. [77]

    Sefusatti, J

    E. Sefusatti, J. R. Fergusson, X. Chen, and E. P. S. Shellard, JCAP08, 033 (2012), arXiv:1204.6318 [astro-ph.CO]

  78. [78]

    J.-O. Gong, S. Pi, and M. Sasaki, JCAP11, 043 (2013), arXiv:1306.3691 [hep-th]

  79. [79]

    X. Chen, Y. Wang, and Z.-Z. Xianyu, (2016), arXiv:1612.08122

  80. [80]

    Arkani-Hamed, D

    N. Arkani-Hamed, D. Baumann, H. Lee, and G. L. Pimentel, JHEP04, 105 (2020), arXiv:1811.00024 [hep-th]

Showing first 80 references.