Pith. sign in

REVIEW 4 major objections 4 minor 51 references

Hidden Adler zeros and soft theorems for inflationary perturbations

T0 review · 4 major / 4 minor · reviewed 2026-08-12 · deepseek-v4-flash

Pith's one-line read Soft theorems for boost-breaking amplitudes become independent of all off-shell cubic vertices under a prescribed ordering of limits.

desk verdict A careful derivation of cubic-independent soft theorems whose central claim rests on a non-standard soft limit; the equivalence to the conventional limit is argued, not proven. read the letter →

arxiv 2411.17591 v7 pith:SGQY6LD5 submitted 2024-11-26 hep-th gr-qc

classification hep-thgr-qc
keywords softtheoremsAdlerzerosboost-breakingamplitudesEFTsofinflationsuperfluidEFTscalinghierarchyWard-Takahashiidentity
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

This paper claims that soft theorems for on-shell scattering amplitudes in boost-breaking theories do not depend on unconstrained off-shell interactions, including cubic vertices, once one adopts the soft hierarchy $q \ll \varepsilon \ll p_a$: the soft momentum is taken to zero while the $i\varepsilon$ regulator stays fixed, and $\varepsilon \to 0$ is taken only at the end. The derivation runs through the Ward-Takahashi identity and LSZ reduction, and shows that with this ordering the left-hand side is fixed by the free equation of motion and the linear part of the symmetry transformation alone. The exchange diagrams whose soft leg attaches to a cubic vertex are collectively indeterminate in the soft limit but acquire an enhanced soft scaling and drop out, so no explicit subtraction of cubic vertices is needed. The paper applies the resulting theorems to the superfluid and scaling superfluid EFTs that arise from the flat-space, decoupling limit of the EFT of inflation, and shows they fix the Wilson coefficients up to known degrees of freedom, matching a Hamiltonian analysis through five points. If the claim is right, the soft theorems for inflationary perturbations are universal, all-orders statements that depend solely on on-shell data.

What carries the argument

The central mechanism is the soft hierarchy $q \ll \varepsilon \ll p_a$: the soft momentum $q$ tends to zero while the $i\varepsilon$ regulator that tames the asymptotic time integrals is kept fixed, and $\varepsilon \to 0$ is taken only after the soft and on-shell limits. This ordering makes the front factor $q^\mu$ from the Ward-Takahashi identity soft enough to kill the collinear poles produced by cubic vertices, so only the linear current $J^\mu_{(1)}$ and the regular part of the quadratic current survive. The energy-flip combinations $\tilde{A}_{E_p}+\tilde{A}_{-E_p}$ and $(\tilde{A}_{E_p}-\tilde{A}_{-E_p})/(2E_p)$ carry the soft information, and the momentum derivatives acting on the energy-momentum delta functions generate the tower structure that matches the inverse Higgs constraints of the symmetry algebra. The $i\varepsilon$ shift is applied exclusively to terms that are divergent or indeterminate in the soft limit, which the paper argues is required for field-redefinition invariance.

What would settle it

Compute the four-point amplitude of the $\dot\pi^3$ vertex, form $(\tilde{A}_{E_1}+\tilde{A}_{-E_1})$ with the $i\varepsilon$ shift applied only to the collinear pole $s_{1,a}$, send $p_1\to0$ with $\varepsilon$ fixed, and then let $\varepsilon\to0$; if any term of order $p_1^0$ or $p_1^1$ survives without matching the right-hand side, the enhanced Adler zero is absent. A complementary check is to compare this regulated soft limit with the standard simultaneous limit $\varepsilon\to0$, $p\to0$ in a one-loop soft amplitude in a boost-breaking theory: any difference would show the hierarchy changes the physics rather than merely ordering two equivalent limits.

Watch

Extended reading notes

Core claim

The central result is a generic soft theorem for non-linearly realised space-time symmetries. For a spatial polynomial shift $\delta^{(0)}\pi = b_{i_1\ldots i_N} x^{i_1}\cdots x^{i_N}$, the theorem takes the form $\lim_{p\to 0} \partial_{p^{i_1}}\cdots\partial_{p^{i_N}}[(\tilde{A}^{n+1}_{E_p}+\tilde{A}^{n+1}_{-E_p})/2] = -\sum_a O_L(p_a,\partial_{p_a}) \tilde{A}^n$, with all lower-derivative towers vanishing; for time-dependent shifts an analogous combination $(\tilde{A}^{n+1}_{E_p}-\tilde{A}^{n+1}_{-E_p})/(2E_p)$ appears. The paper's key assertion is that $O_L$ and the right-hand side are determined only by the free theory and the linear part of the symmetry, never by unconstrained cubic vertices, provided the soft hierarchy is enforced. Specialising to the non-linear boost $\delta_B\pi = b_i[x_i + (x_i\partial_t + t\partial_i)\pi]$ gives the superfluid soft theorems, and adding the non-linear dilatation gives the scaling superfluid theorems; in both cases the paper checks the constraints against explicit amplitudes and a Hamiltonian analysis up to five points. It also shows that the sum of exchange diagrams whose soft momentum is attached to a cubic vertex and which are singular in the collinear limit has an enhanced soft scaling $O(p_1^2)$, and that the $i\varepsilon$ prescription restricted to divergent or indeterminate terms guarantees field-basis independence.

Load-bearing premise

The load-bearing premise is that the soft hierarchy $q \ll \varepsilon \ll p_a$ is the physically correct order of limits: sending the soft momentum to zero while the $i\varepsilon$ regulator is held fixed, and only afterwards letting $\varepsilon\to0$, reproduces the ordinary soft limit of the S-matrix and of phase-space integrals.

Editorial extensions

If this is right

  • Off-shell cubic vertices no longer need to be subtracted or assumed absent: the collection of exchange diagrams carrying a soft cubic vertex vanishes collectively with an enhanced $O(p_1^2)$ Adler zero.
  • For the superfluid EFT, the non-linear boost soft theorem fixes the Wilson coefficients up to one unconstrained coefficient per order in the field, agreeing with the Hamiltonian analysis through five points.
  • For the scaling superfluid, the additional non-linear dilatation soft theorem fixes even the three-point amplitude, leaving only the sound-speed parameter $c_s$ as a free input.
  • Field-basis independence follows from applying $i\varepsilon$ only to terms that are divergent or indeterminate in the soft limit, so on-shell soft theorems are stable under field redefinitions within the minimal basis.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the soft hierarchy is the physically correct definition of the soft limit, the same mechanism should carry over to unequal-time correlators and wavefunction coefficients through the flat-space residue relation; the paper gestures at this but does not prove it.
  • A diagrammatic selection rule suggests itself: in boost-breaking EFTs, soft emissions attached to cubic vertices through collinear poles can be dropped from the start of a soft bootstrap, which would simplify higher-point constructions.
  • A natural stress test the paper leaves open is non-linear dispersion relations such as the ghost condensate, where the free theory is not $E=|\vec p|$; whether the hierarchy argument survives that change is not addressed.
  • The intermediate regulator dependence (terms such as $E_1^2/(i\varepsilon)$) means the theorem is tied to a non-standard ordering of limits; if the conventional $\varepsilon\to0$ before $p\to0$ limit is used instead, the claimed cubic-independence would need to be reconsidered.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 4 minor

Summary. The paper derives soft theorems for on-shell scattering amplitudes from non-linearly realised spacetime symmetries arising in the flat-space and decoupling limits of the EFT of inflation. The derivation follows the Noether-current route: a Ward-Takahashi identity is LSZ-reduced, and a new 'soft hierarchy' q << eps << p is imposed, with eps kept fixed while the soft momentum goes to zero and eps tending to zero only at the end. The central claim is that, under this hierarchy, the soft theorems are independent of unconstrained off-shell cubic vertices, depend only on on-shell data, and hold to all orders in perturbation theory. The paper works out polynomial shift symmetries, the non-linear boost symmetry of the superfluid EFT, and the combined boost-dilatation symmetry of the scaling superfluid, and uses the theorems to bootstrap Wilson coefficients up to five points, matching a Hamiltonian analysis.

Significance. If the central claim is correct, this is a significant step: it would remove the long-standing obstruction that soft theorems for boost-breaking amplitudes require explicit subtraction of soft-cubic-vertex contributions, and it would turn the soft theorems into a systematic bootstrap for superfluid and inflationary EFTs. The paper's strengths are the explicit tree-level checks, the careful treatment of the minimal basis and energy-momentum delta functions, the concrete cancellation mechanism in Eq. (7.4), and the explicit agreement with Hamiltonian Wilson coefficients at five points. The main unresolved issue is the status of the nonstandard order of limits, which is load-bearing for the all-orders and cubic-independence claims.

major comments (4)
  1. [Sec. 3.5, Eq. (3.51); Sec. 7, Eq. (7.4)] The central claim is derived under the soft hierarchy q << eps << p, with eps kept fixed while q goes to zero and eps going to zero only at the end. The paper argues that this corresponds to phase-space integration of cross-sections, but it does not prove that this regulated limit equals the conventional soft limit of the on-shell S-matrix, where the Feynman i eps is removed when the amplitude is defined as a distribution. Eq. (7.4) makes the issue concrete: the O(p1^2) enhanced scaling of the sum of soft-cubic exchange diagrams is obtained by expanding with eps fixed, and without this order of limits the poles at s_{1,a}=0 do not cancel in the same way. Since the abstract's all-orders cubic-independence statement depends on this order of limits, the manuscript must either prove that the two limits commute or explicitly state that the theorem refers to this regulated soft limit rather than to the conventional amplitude soft limit.
  2. [Sec. 3.2, Eqs. (3.28)-(3.40)] The reduction of the quadratic-current contribution G(2) to a regular term determined only by free-field data and symmetry variation, and the vanishing G(m)=0 for m>2, are asserted in general but demonstrated only for the specific boost current in Section 5. The text states that the factorization 'holds for all loop orders' and cites Ref. [38], but no loop-level derivation of the pole structure or of the soft limit is provided. Thus the 'all orders in perturbation theory' claim in the abstract and in Eqs. (3.45)-(3.49) is not backed by the derivation as written. Either supply a general argument, including at least one explicit loop-level check, or restrict the claim to tree level.
  3. [Sec. 3.3, Eqs. (3.42)-(3.44)] The RHS of the Ward-Takahashi identity is set to zero by applying the i eps shift to the LSZ pole at p0_a = E_{p_a+q} - q0 and then taking p0_a -> E_a with eps fixed. This step is not derived, and it is not the same as the treatment in Section 2, where the same kind of regulated pole was expanded and produced the nontrivial boost and rotation constraints. As written, the argument seems capable of eliminating the external-leg variation for any symmetry, so the reader cannot tell which contributions are being discarded. A derivation showing that the combination of the soft limit and the eps-fixed prescription makes these terms vanish without also killing the constraints of Section 2 is needed.
  4. [Sec. 7, Eqs. (7.5)-(7.7)] The enhanced Adler zero for the collection of soft-cubic exchange diagrams relies on the specific energy-dependent imaginary part in the propagator 1/[2(s_{1,a}+i eps E_{1a})]; replacing it by 1/[2(s_{1,a}+i eps)] breaks the cancellation. Since the standard Feynman prescription is usually stated with a momentum-independent i eps, the paper should explain why this particular energy-dependent form is the correct physical regulator for the on-shell amplitudes considered here, and how this choice is compatible with the conventional definition of the S-matrix.
minor comments (4)
  1. [Eq. (1.17) and Fig. 3 vs. text near Eq. (3.18)] The four-vector notation for the energy-flipped state is inconsistent: Eq. (1.17) and Fig. 3 set p' = (-E_p, p), while the text below Eq. (3.18) defines q' = (E_q, -q). Please make the sign convention uniform throughout.
  2. [Sec. 1, Summary of results] There are typos in the summary: 'flat space and decoupling limts' should be 'limits', and 'superluid' should be 'superfluid'.
  3. [Sec. 5, Eqs. (5.26)-(5.31)] The notation g^H_{m,n} for Hamiltonian Wilson coefficients is used before the subscript convention is explained; a short definition of m and n (e.g. total derivative order and number of spatial derivatives) would help the reader.
  4. [Sec. 6, around Eq. (6.21)] The two-point 'amplitude' with the dimensionless factor delta(0) is unusual; the replacement delta(E2-E3) -> delta(0)/E2 deserves a comment on why this normalization is consistent with the standard LSZ reduction for two-point functions.

Circularity Check

2 steps flagged · score 6.0 of 10

The claimed cubic-vertex independence is enforced by the chosen q<<ε soft hierarchy rather than derived, and the generic theorem's tower structure is imported from the author's own [31].

  1. self definitional [Section 3.2 (Eqs. 3.34-3.36) and Section 3.5 (Eq. 3.51); applied in Eq. (7.4)]
    "The divergent term G+(2)|div, upon imposing soft hierarchy, vanishes in the soft limit by sending the front factor qµ → 0 as we keep iε fixed. ... if we do not send q → 0 before ε → 0, the front factor qµ is not soft enough to cancel out the pole in G+(2)|div, which would yield an indeterminate limit. However, if we impose the soft hierarchy where we treat ε as an IR regulator, G+(2)|div again vanishes."

    The central claim that unconstrained off-shell cubic vertices never enter the soft theorem is produced by the chosen order of limits, not by the dynamics of the amplitudes. With the hierarchy q << ε, the would-be singular propagator 1/(s1,a + iεE1a) is evaluated at finite ε while q → 0, so the numerator soft-momentum factor makes each soft-cubic exchange diagram O(q^2/ε) → 0 before ε → 0 (Eq. 7.4). The paper argues, but does not prove, that this hierarchy reproduces the physical cross-section-regulated soft limit; if the conventional amplitude soft limit takes ε → 0 first, the cubic terms do not cancel in the same way, as the paper itself concedes in Section 7. The 'prediction' of cubic independence is therefore equivalent, by construction, to the input definition of the soft limit.

  2. self citation load bearing [Section 3.2, paragraph after Eq. (3.19); Section 3.4]
    "The upshot is that derivatives acting on spatial δd(⃗ p+ ⃗ q) would generate a tower structure yielding [31] ... We refer readers to [31] for a more comprehensive discussion of this tower structure."

    The generic soft theorem (3.45)-(3.49) inherits its detailed structure—which derivative orders vanish and the tower of lower-derivative equations—from [31], the author's own prior work, rather than from a derivation reproduced in this paper. The paper repeatedly outsources the tower structure to [31] ('as explained in [31]'), and no machine-checked or otherwise independent verification of that structure is provided here. Since the final theorem's content depends on this self-citation, the self-citation is load-bearing for the central claim, even though the tower structure may in principle be derivable from delta-function identities.

full rationale

The derivation is not wholly circular: the soft theorems are obtained from the Ward-Takahashi identity with an explicit LSZ reduction, the current is split by order in π, and the bootstrap checks against explicit Hamiltonian Wilson coefficients (Sections 5.2 and 6) are genuine, independent consistency tests. The paper also explicitly reproduces the enhanced O(p1^2) scaling of the summed soft-cubic exchange diagrams in Eq. (7.4). However, the central claim that unconstrained off-shell cubic vertices never enter the soft theorem is an artifact of the 'soft hierarchy' q << ε, with ε held fixed while q → 0: in this order of limits the would-be singular propagators are evaluated at finite ε, so the numerator momentum factor forces every such diagram to vanish before ε → 0. The paper asserts, but does not prove, that this hierarchy matches the physical phase-space-regulated soft limit; if the conventional amplitude limit takes ε → 0 first, the cubic terms do not cancel in the same way, as the paper itself notes: 'The soft theorem would fail to hold if we absorb the energy dependence of the imaginary shift into ε.' Additionally, the full form of the generic soft theorem—especially the tower of vanishing lower-derivative equations—is inherited from the author's previous work [31] by citation rather than derived here. These two moves make the central 'model independence' claim substantially definitional, though the Ward-identity framework and the explicit bootstrap checks provide independent content that prevents the paper from being completely circular.

Assumptions & free parameters 0 free parameters · 6 assumptions · 0 invented entities

No parameters are fitted to data in this paper. The sound speed cs and the coefficients M3, M4, M5 are inputs of the superfluid and scaling superfluid EFTs and remain free in the bootstrap; they are not adjusted to make the soft theorems work. No new particles, forces, or conserved quantities are introduced. The load-bearing premises are the soft hierarchy and the selective iε rule, which are imposed rather than derived from standard S-matrix definitions.

assumptions (6)
  • domain assumption The interaction vacuum is annihilated by Lorentz generators even though the background and interactions break Lorentz invariance.
    Assumptions bullet, Eq. (1.14). Needed so the integrated Ward-Takahashi boundary term can be written as a current insertion; if this fails, the soft theorem derivation changes.
  • domain assumption The free theory is the two-derivative canonical scalar with linear dispersion E = |p| and no tadpole.
    Assumptions section and Eq. (8.1). The LSZ residues and the current expansion J_(1), J_(2), ... assume this free Lagrangian. Non-linear dispersions are left to future work.
  • ad hoc to paper Soft hierarchy q << ε << p_a: soft momentum and on-shell residues go to zero while the iε regulator is kept fixed; ε→0 is taken last.
    Section 3.5, Eq. (3.51) and Figure 2. This ordering makes G(2)|div and the RHS vanish; it is not a standard feature of S-matrix definitions.
  • ad hoc to paper The iε shift is applied only to terms that are divergent or indeterminate in the limit; regular terms do not receive a regulator.
    Section 3.5 and the λϕ example (Eqs. 3.52-3.55). This selective regularization is needed for field-redefinition invariance of the soft theorem.
  • domain assumption Multi-particle intermediate states do not contribute to the LSZ residue because they are regular in the soft and on-shell limits.
    Section 3.2, near Eq. (3.17). The paper says an effective mass suppresses IR divergence; for massless fields this is not obvious and no loop computation is given.
  • standard math Ward-Takahashi identity and LSZ reduction are valid for non-linearly realised symmetries with the boundary term regulated by the iε prescription.
    Sections 2-3. The entire derivation converts symmetry currents into amplitude constraints through these standard QFT tools.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Hidden Adler zeros and soft theorems for inflationary perturbations." pith.science (2026). https://pith.science/paper/SGQY6LD5

@misc{pith2026241117591,
  author       = {Pith},
  title        = {Pith review of: Hidden Adler zeros and soft theorems for inflationary perturbations},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/SGQY6LD5}},
  note         = {Machine review of arXiv:2411.17591}
}
abstract

We derive soft theorems for on-shell scattering amplitudes from non-linearly realised global space-time symmetries, arising from the flat space and decoupling limits of the effective field theories (EFTs) of inflation, while taking particular care of on-shell limits, soft limits, time-ordered correlations, momentum derivatives, energy-momentum conserving delta functions and $i\varepsilon$ prescriptions. Intriguingly, contrary to common belief, we find with a preferred soft hierarchy among the soft momentum $q$, on-shell residue $p_a^0 \pm E_a$, and $\varepsilon$, the soft theorems do not have dependence on unconstrained off-shell interactions, even in the presence of cubic vertices. We also argue that the soft hierarchy is a natural choice, ensuring the soft limit and on-shell limit commute. Our soft theorems depend solely on on-shell data and hold to all orders in perturbation theory. We present various examples including polynomial shift symmetries, non-linear realisation of Lorentz boosts and dilatations on how the soft theorems work. We find that the collection of exchange diagrams whose soft momenta are associated with cubic vertices, that are indeterminate in the soft limit, exhibits an enhanced soft scaling. The enhanced soft scaling explains why the sum of such diagrams do not enter the soft theorems non-trivially. We further apply the soft theorems to bootstrap the scattering amplitudes of the superfluid and scaling superfluid EFTs, finding agreement with the Hamiltonian analysis.

Figures

Figures reproduced from arXiv: 2411.17591 by the authors.

Figure 1
Figure 1. Schematic route for deriving scattering amplitude constraints from symmetries [PITH_FULL_IMAGE:figures/full_fig_p004_1.png] view at source ↗
Figure 2
Figure 2. A diagram representation for the soft hierarchy. The ( [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 3
Figure 3. A graphical representation for the energy flipping scattering amplitude. [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figures from the paper (3 more)
Figure 4
Figure 4. Figure 4: A graphic representation of non vanishing boundary integral of Ward Takahashi identity. When [PITH_FULL_IMAGE:figures/full_fig_p013_4.png]
Figure 5
Figure 5. Figure 5: Non-linear boost soft theorem constraints on superfluid Wilson coefficients. Black legs denote [PITH_FULL_IMAGE:figures/full_fig_p027_5.png]
Figure 6
Figure 6. Figure 6: The sum of diagrams that contain 3-point soft vertices have an enhanced Adler zero [PITH_FULL_IMAGE:figures/full_fig_p031_6.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

51 extracted references · 8 canonical work pages

  1. [31]

    Soft Theorems for Boostless Amplitudes

    Z. Du and D. Stefanyszyn, Soft Theorems for Boostless Amplitudes , 2403.05459

  2. [38]

    Cohen, X

    T. Cohen, X. Lu and D. Sutherland, On Amplitudes and Field Redefinitions , 2312.06748

  3. [1]

    Cheung, K

    C. Cheung, K. Kampf, J. Novotny and J. Trnka, Effective Field Theories from Soft Limits of Scattering Amplitudes, Phys. Rev. Lett. 114 (2015) 221602 [ 1412.4095]

  4. [2]

    Adler, Consistency conditions on the strong interactions implied by a partially conserved axial-vector current

    S.L. Adler, Consistency conditions on the strong interactions implied by a partially conserved axial-vector current. II , Phys. Rev. 139 (1965) B1638

  5. [3]

    Cheung, K

    C. Cheung, K. Kampf, J. Novotny, C.-H. Shen and J. Trnka, A Periodic Table of Effective Field Theories, JHEP 02 (2017) 020 [ 1611.03137]

  6. [4]

    Hinterbichler and A

    K. Hinterbichler and A. Joyce, Hidden symmetry of the Galileon , Phys. Rev. D 92 (2015) 023503 [1501.07600]

  7. [5]

    Padilla, D

    A. Padilla, D. Stefanyszyn and T. Wilson, Probing Scalar Effective Field Theories with the Soft Limits of Scattering Amplitudes , JHEP 04 (2017) 015 [ 1612.04283]

  8. [6]

    Cheung, K

    C. Cheung, K. Kampf, J. Novotny, C.-H. Shen and J. Trnka, On-Shell Recursion Relations for Effective Field Theories , Phys. Rev. Lett. 116 (2016) 041601 [ 1509.03309]

Show all 51 references
  1. [7]

    Cheung, K

    C. Cheung, K. Kampf, J. Novotny, C.-H. Shen, J. Trnka and C. Wen, Vector Effective Field Theories from Soft Limits , Phys. Rev. Lett. 120 (2018) 261602 [ 1801.01496]. 34

  2. [8]

    Bonifacio, K

    J. Bonifacio, K. Hinterbichler, L.A. Johnson, A. Joyce and R.A. Rosen, Matter Couplings and Equivalence Principles for Soft Scalars , JHEP 07 (2020) 056 [ 1911.04490]

  3. [9]

    Brauner, A

    T. Brauner, A. Esposito and R. Penco, Fractional Soft Limits of Scattering Amplitudes , Phys. Rev. Lett. 128 (2022) 231601 [ 2203.00022]

  4. [10]

    Carrillo Gonz´ alez, R

    M. Carrillo Gonz´ alez, R. Penco and M. Trodden, Shift symmetries, soft limits, and the double copy beyond leading order, Phys. Rev. D 102 (2020) 105011 [ 1908.07531]

  5. [11]

    Bartsch, K

    C. Bartsch, K. Kampf and J. Trnka, Recursion relations for one-loop Goldstone boson amplitudes , Phys. Rev. D 106 (2022) 076008 [ 2206.04694]

  6. [12]

    G. Goon, S. Melville and J. Noller, Quantum corrections to generic branes: DBI, NLSM, and more , JHEP 01 (2021) 159 [ 2010.05913]

  7. [13]

    Cheung, A

    C. Cheung, A. Helset and J. Parra-Martinez, Geometric soft theorems, JHEP 04 (2022) 011 [2111.03045]

  8. [14]

    Di Vecchia, R

    P. Di Vecchia, R. Marotta, M. Mojaza and J. Nohle, New soft theorems for the gravity dilaton and the Nambu-Goldstone dilaton at subsubleading order , Phys. Rev. D 93 (2016) 085015 [ 1512.03316]

  9. [15]

    Derda, A

    M. Derda, A. Helset and J. Parra-Martinez, Soft scalars in effective field theory , JHEP 06 (2024) 133 [2403.12142]

  10. [16]

    Kampf, J

    K. Kampf, J. Novotny, M. Shifman and J. Trnka, New Soft Theorems for Goldstone Boson Amplitudes, Phys. Rev. Lett. 124 (2020) 111601 [ 1910.04766]

  11. [17]

    Arkani-Hamed, Q

    N. Arkani-Hamed, Q. Cao, J. Dong, C. Figueiredo and S. He, Hidden zeros for particle/string amplitudes and the unity of colored scalars, pions and gluons , 2312.16282

  12. [18]

    Y. Li, D. Roest and T. ter Veldhuis, Hidden Zeros in Scaffolded General Relativity and Exceptional Field Theories, 2403.12939

  13. [19]

    Cheung, P

    C. Cheung, P. Creminelli, A.L. Fitzpatrick, J. Kaplan and L. Senatore, The Effective Field Theory of Inflation , JHEP 03 (2008) 014 [ 0709.0293]

  14. [20]

    Maldacena and G.L

    J.M. Maldacena and G.L. Pimentel, On graviton non-Gaussianities during inflation , JHEP 09 (2011) 045 [ 1104.2846]

  15. [21]

    Baumann, D

    D. Baumann, D. Green, A. Joyce, E. Pajer, G.L. Pimentel, C. Sleight et al., Snowmass White Paper: The Cosmological Bootstrap , in 2022 Snowmass Summer Study , 3, 2022 [ 2203.08121]

  16. [22]

    Benincasa, Amplitudes meet Cosmology: A (Scalar) Primer , 2203.15330

    P. Benincasa, Amplitudes meet Cosmology: A (Scalar) Primer , 2203.15330

  17. [23]

    Benincasa, Wavefunctionals/S-matrix techniques in de Sitter , in 21st Hellenic School and Workshops on Elementary Particle Physics and Gravity , 3, 2022 [ 2203.16378]

    P. Benincasa, Wavefunctionals/S-matrix techniques in de Sitter , in 21st Hellenic School and Workshops on Elementary Particle Physics and Gravity , 3, 2022 [ 2203.16378]

  18. [24]

    Bonifacio, H

    J. Bonifacio, H. Goodhew, A. Joyce, E. Pajer and D. Stefanyszyn, The graviton four-point function in de Sitter space , 2212.07370

  19. [25]

    Baumann, C

    D. Baumann, C. Duaso Pueyo, A. Joyce, H. Lee and G.L. Pimentel, The Cosmological Bootstrap: Spinning Correlators from Symmetries and Factorization , 2005.04234

  20. [26]

    Baumann, W.-M

    D. Baumann, W.-M. Chen, C. Duaso Pueyo, A. Joyce, H. Lee and G.L. Pimentel, Linking the Singularities of Cosmological Correlators , 2106.05294. 35

  21. [27]

    Jazayeri and S

    S. Jazayeri and S. Renaux-Petel, Cosmological Bootstrap in Slow Motion , 2205.10340

  22. [28]

    Mei and Y

    J. Mei and Y. Mo, On-shell Bootstrap for n-gluons and gravitons scattering in (A)dS, Unitarity and Soft limit , 2402.09111

  23. [29]

    Green, Y

    D. Green, Y. Huang and C.-H. Shen, Inflationary Adler conditions , Phys. Rev. D 107 (2023) 043534 [2208.14544]

  24. [30]

    Mojahed and T

    M.A. Mojahed and T. Brauner, Nonrelativistic effective field theories with enhanced symmetries and soft behavior, JHEP 03 (2022) 086 [ 2201.01393]

  25. [32]

    Cheung, M

    C. Cheung, M. Derda, A. Helset and J. Parra-Martinez, Soft Phonon Theorems , 2301.11363

  26. [33]

    L. Hui, A. Joyce, I. Komissarov, K. Parmentier, L. Santoni and S.S.C. Wong, Soft theorems for boosts and other time symmetries , JHEP 02 (2023) 123 [ 2210.16276]

  27. [34]

    Bittermann and A

    N. Bittermann and A. Joyce, Soft limits of the wavefunction in exceptional scalar theories , 2203.05576

  28. [35]

    Pajer and D

    E. Pajer and D. Stefanyszyn, Symmetric Superfluids, JHEP 06 (2019) 008 [ 1812.05133]

  29. [36]

    Grall, S

    T. Grall, S. Jazayeri and D. Stefanyszyn, The cosmological phonon: symmetries and amplitudes on sub-horizon scales, JHEP 11 (2020) 097 [ 2005.12937]

  30. [37]

    Peskin and D.V

    M.E. Peskin and D.V. Schroeder, An Introduction to quantum field theory , Addison-Wesley, Reading, USA (1995), 10.1201/9780429503559

  31. [39]

    Creminelli, O

    P. Creminelli, O. Janssen and L. Senatore, Positivity bounds on effective field theories with spontaneously broken Lorentz invariance, JHEP 09 (2022) 201 [ 2207.14224]

  32. [40]

    Raju, New Recursion Relations and a Flat Space Limit for AdS/CFT Correlators , Phys

    S. Raju, New Recursion Relations and a Flat Space Limit for AdS/CFT Correlators , Phys. Rev. D 85 (2012) 126009 [ 1201.6449]

  33. [41]

    Baumann and D

    D. Baumann and D. Green, Equilateral Non-Gaussianity and New Physics on the Horizon , JCAP 09 (2011) 014 [ 1102.5343]

  34. [42]

    Nicolis, R

    A. Nicolis, R. Penco, F. Piazza and R. Rattazzi, Zoology of condensed matter: Framids, ordinary stuff, extra-ordinary stuff , JHEP 06 (2015) 155 [ 1501.03845]

  35. [43]

    Roest, D

    D. Roest, D. Stefanyszyn and P. Werkman, An Algebraic Classification of Exceptional EFTs Part II: Supersymmetry, JHEP 11 (2019) 077 [ 1905.05872]

  36. [44]

    Finelli, G

    B. Finelli, G. Goon, E. Pajer and L. Santoni, The Effective Theory of Shift-Symmetric Cosmologies , JCAP 05 (2018) 060 [ 1802.01580]

  37. [45]

    Green and E

    D. Green and E. Pajer, On the Symmetries of Cosmological Perturbations , 2004.09587

  38. [46]

    Monin, D

    A. Monin, D. Pirtskhalava, R. Rattazzi and F.K. Seibold, Semiclassics, Goldstone Bosons and CFT data, JHEP 06 (2017) 011 [ 1611.02912]

  39. [47]

    Arkani-Hamed, H.-C

    N. Arkani-Hamed, H.-C. Cheng, M.A. Luty and S. Mukohyama, Ghost condensation and a consistent infrared modification of gravity, JHEP 05 (2004) 074 [ hep-th/0312099]. 36

  40. [48]

    Creminelli, J

    P. Creminelli, J. Nore˜ na and M. Simonovi´ c,Conformal consistency relations for single-field inflation, JCAP 07 (2012) 052 [ 1203.4595]

  41. [49]

    Qin, Cosmological Correlators at the Loop Level , 2411.13636

    Z. Qin, Cosmological Correlators at the Loop Level , 2411.13636

  42. [50]

    Pajer, D

    E. Pajer, D. Stefanyszyn and J. Supe l, The Boostless Bootstrap: Amplitudes without Lorentz boosts , JHEP 12 (2020) 198 [ 2007.00027]

  43. [51]

    Chen, M.-x

    X. Chen, M.-x. Huang and G. Shiu, The Inflationary Trispectrum for Models with Large Non-Gaussianities, Phys. Rev. D 74 (2006) 121301 [ hep-th/0610235]. 37

Pith tools

Reviewed August 12, 2026 · model on record in the stance chip above.