Pith. sign in

REVIEW 3 major objections 4 minor 13 cited by

(Super)$\,$Gravity from Positivity

T0 review · 3 major / 4 minor · reviewed 2026-08-06 · deepseek-v4-flash

Pith's one-line read A lone massive spin-3/2 particle is ruled out by causality

desk verdict Most substantial spin-3/2 positivity result to date: gravity and g=2 emerge inside a finite low-spin spectrum, but the abstract overstates the 'gravity is necessary' claim by dropping that restriction. read the letter →

arxiv 2507.12535 v1 pith:6CIKON2M submitted 2025-07-16 hep-th hep-ph

classification hep-thhep-ph PACS 04.65.+e11.55.-m
keywords spin-3/2positivityboundssupergravitygravitinoGoldstinoEFT-hedronweakgravityconjecturegyromagneticratio
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 asks whether a weakly coupled effective field theory (EFT) for a single massive spin-3/2 particle can be consistent with causality and unitarity, as encoded in positivity bounds on scattering amplitudes. It finds that no such theory exists unless a massless graviton is included and coupled in a nearly supersymmetric way, with the specific tuning $F^2 = 3m^2 M_P^2$ that makes the spin-3/2 particle a gravitino. An isolated Majorana spin-3/2 particle is either free or has a cutoff near its own mass, at most about $9m$. For a Dirac spin-3/2 carrying a U(1) charge, consistency also requires a photon that gauges the symmetry, with a charge-to-mass ratio saturating the weak gravity conjecture and gyromagnetic factor $g=2$. The paper further develops novel $t$-$u$ symmetric dispersion relations for the longitudinal (Goldstino) polarizations, mapping an EFT-hedron whose corners are known supersymmetry-breaking models.

What carries the argument

The engine of the argument is a set of 'Arc' contour integrals around low-energy singularities of $2\to 2$ amplitudes; unitarity and analyticity bound every non-forward, inelastic Arc by forward elastic Arcs (Eq. 2.2), so no EFT amplitude can have a term growing faster than $E^4$. Applying these bounds iteratively in decoupling limits ($m\to 0$, $M_P\to\infty$ at fixed $F^2 = 3m^2 M_P^2$) fixes the Wilson coefficients to the gravitino values and sets all electromagnetic and gravitational multipoles to zero. Section 5 introduces a new class of $t$-$u$ symmetric dispersion relations for Goldstino scattering, organized by $p^2 = tu/s$, which package the full set of null constraints and define the Goldstino EFT-hedron, the allowed space of Wilson coefficients.

What would settle it

Exhibit an explicit weakly coupled EFT of a single massive Majorana spin-3/2 particle with only scalar and vector exchanges, no graviton, whose amplitudes satisfy the full Arc bounds of Eq. (2.2) for a cutoff $\Lambda \gg m$; Section 3.2 states no such solution exists. Alternatively, compute the finite-$m/\Lambda$ corrections to the bounds in the gravity-inclusive case and show that the allowed region disagrees with the tuning $F^2 = 3m^2 M_P^2$.

Watch

Extended reading notes

Core claim

The central claim is that an isolated massive spin-3/2 particle with a large separation between its mass $m$ and the EFT cutoff $\Lambda$ violates positivity of scattering amplitudes. Imposing the bounds iteratively—cancelling the $E^6$ growth, then the $E^5$ and $E^4$ terms—forces every non-trivial solution to include a massless graviton with fixed couplings: the gravitational multipoles must vanish and the longitudinal sector must match a Goldstino with decay constant $F^2 = 3m^2 M_P^2$, the signature of spontaneously broken $N=1$ supergravity. In the Dirac case with a global U(1) symmetry, a massless photon must gauge the symmetry with $q^2 e^2 / m^2 = 1/(2M_P^2)$ and $g = 2$, so the no-global-symmetry and weak-gravity conjectures arise as consequences of causality and unitarity. The same machinery bounds the space of Goldstino Wilson coefficients, whose extremal points are scalar-exchange and vector-exchange supersymmetry-breaking models together with higher-spin and string-like amplitudes.

Load-bearing premise

The conclusion that gravity is unavoidable assumes that the only extra light degrees of freedom are spin-0, spin-1, and a single massless spin-2 particle, and that bounds computed in the $m\to 0$ decoupling limit hold at finite mass up to $O(m/\Lambda)$ corrections.

Editorial extensions

If this is right

  • A weakly coupled massive spin-3/2 state cannot be the only new light state: either its EFT has cutoff near its mass (about $9m$ for the isolated Majorana case) or gravity enters the low-energy spectrum.
  • The consistent couplings are those of spontaneously broken $N=1$ supergravity: the spin-3/2 particle behaves as a gravitino with $F^2 = 3m^2 M_P^2$, and all gravitational multipoles vanish.
  • A charged Dirac spin-3/2 forces the U(1) symmetry to be gauged, so global symmetries are absent in this gravitational EFT and the weak gravity conjecture is saturated, with $g = 2$.
  • Deviations from these tunings are allowed only at subleading order—for example $g-2 = O(m/M_P)$ when extra light vectors are present—so measuring such a deviation indicates additional states below the Planck scale.
  • The Goldstino EFT-hedron has corners at scalar-exchange (F-term) and vector-exchange (D-term) supersymmetry-breaking models, and also admits higher-spin and string-like extremal amplitudes.

Reading between the lines

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

  • Editorial inference: the same iterative positivity machinery could put quantitative upper bounds on Kaluza-Klein mass gaps for massive spin-2 states in compactified theories, an application the paper lists as future work.
  • Editorial inference: the all-multipoles-vanish result suggests a first-principles selection rule for three-point amplitudes of classical spinning bodies in gravitational-wave physics, where such couplings are normally chosen by hand.
  • Editorial inference: a measurement of the gyromagnetic ratio of any future spin-3/2 resonance is a concrete test: a value with $g-2$ larger than $O(m/M_P)$ would rule out the minimal supergravity interpretation and imply nearby new states.
  • Editorial inference: the paper's own Section 5.4 shows that if an infinite tower of higher-spin states is allowed, Goldstino consistency can be achieved without gravitons in that truncated sector; a fully non-perturbative completion could therefore, in principle, evade the gravitational bootstrap.
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

3 major / 4 minor

Summary. The paper studies whether a weakly coupled effective field theory (EFT) of a single massive spin-3/2 particle with a large cutoff can be consistent with causality and unitarity, phrased as positivity of two-to-two amplitudes. Using on-shell amplitude methods and Arc-type positivity bounds, it claims that an isolated Majorana spin-3/2 EFT has no nontrivial solution unless a massless graviton is included with couplings fixed to supersymmetric values, in particular F^2 = 3 m^2 M_P^2 (Eq. 3.21). For a U(1)-charged Dirac spin-3/2 particle, the same logic is argued to require both a graviton and a photon gauging the U(1), with g = 2 and q^2 e^2/m^2 = 1/(2 M_P^2) (Eqs. 4.12, 4.13). The paper then develops a new class of t-u symmetric dispersion relations for the longitudinal (Goldstino) sector, derives an infinite set of null constraints, and maps the allowed EFT-hedron, identifying extremal models including O'Raifeartaigh, Fayet-Iliopoulos, s/tu, and Lovelace-Shapiro amplitudes.

Significance. If the central claims hold, the paper provides a striking bottom-up argument that causality and unitarity alone force a supergravity-like structure for a light massive spin-3/2 state, together with the no-global-symmetry conjecture and weak-gravity-conjecture saturation. The technical work is substantial: the on-shell three-point amplitude classification, the algorithmic construction of four-point amplitudes via MassiveGraphs, and the detailed derivation of positivity bounds in Appendix B are careful and reproducible, with an ancillary amplitude file provided. The finite-mass treatment of the isolated Majorana case (Appendix B.4) and the falsifiable prediction Lambda/m <~ 9 are concrete assets. The main caveat is that the headline 'gravity is necessary' is proven only under an explicit restriction to a finite low-spin spectrum; the paper's own Section 5.4 shows that infinite higher-spin towers can satisfy the Goldstino-sector positivity constraints without a massless graviton.

major comments (3)
  1. [§2.1, Step 4; §3.2; Abstract; §6] The proof that gravity is necessary assumes that the additional light spectrum is restricted to spin-0, spin-1, and one massless spin-2 particle. This is stated in Section 2.1, Step 4, and the Introduction's parenthetical '(with finite number of degrees of freedom)' is an important qualification. However, the Abstract and the headline conclusion 'Gravity is necessary' in Section 3.2 and Section 6 drop this qualification. The paper's own Section 5.4 exhibits infinite higher-spin amplitudes (Eqs. 5.47, 5.50, 5.51) that satisfy the Goldstino-sector positivity and null constraints without a massless graviton. Since the no-solution proof of Sections 3-4 is not extended to spectra containing infinite higher-spin towers, the claim as stated in the Abstract is stronger than what is established. Please either extend the no-go theorem to arbitrary higher-spin towers or qualify the Abstract and conclusions to state explicitly that the result applies to EFTs with a finite number of low-spin degrees of freedom.
  2. [§2.1; Appendix B.4; Eqs. (3.18), (4.10), (4.13)] The central tunings are derived in the decoupling limit m -> 0, M_P -> infinity with F fixed, and the paper repeatedly states that finite-mass corrections are of order O(m/Lambda). The only worked demonstration of this estimate is the isolated Majorana case in Appendix B.4 (Eqs. B.27-B.30). For the gravity-inclusive cases in Sections 3.2 and 4.2, the forward limit t -> 0 is singular due to the graviton pole, and the decoupling and t -> 0 limits are noted to not commute. No explicit finite-mass bound is provided for these cases. Since the existence of a large-cutoff EFT requires m << Lambda, the robustness of the tunings to finite m/Lambda is load-bearing. Please provide at least a controlled estimate or a precise statement of the unproven assumption.
  3. [§5.4, Eqs. (5.47)-(5.51)] The higher-spin amplitudes labeled as 'models' in Section 5.4 satisfy the Goldstino-sector constraints, but the paper does not show that they satisfy the full positivity constraints for the complete massive spin-3/2 amplitudes including transverse polarizations. Footnote 20 correctly notes that additional constraints may arise when the extra states appear on external legs. This means the s/tu and Lovelace-Shapiro examples do not yet constitute counterexamples to gravity necessity for the full theory, but they do show that the longitudinal-sector constraints alone do not select gravity. The conclusions should be phrased so that this distinction is explicit: the EFT-hedron analysis constrains the Goldstino sector, while the necessity of gravity is a statement about the finite low-spin class.
minor comments (4)
  1. [§1] There is a typo in the conventions sentence: 'togheter' should be 'together'.
  2. [§5.2, Eq. (5.11)] The notation in Eq. (5.11) writes '1/sn ds/s', which is ambiguous; the integration measure and the power of s should be defined in a consistent way, e.g. f(s,t(s,p^2)) ds/s^(n+1).
  3. [§3.1 and Appendix B.4] The main text quotes Eq. (3.9) as 'Lambda <~ 9m', while Appendix B.4 reports the sharper numerical bound 'Lambda < 8.2m'; please reconcile these two statements or explain that the former is a rounder estimate.
  4. [§5.4] The footnote describing why the higher-spin examples are called 'models' rather than 'UV completions' is important and would benefit from being moved into the main text, since it directly bears on the scope of the positivity constraints satisfied by those amplitudes.

Circularity Check

0 steps flagged · score 1.0 of 10

No material circularity: the headline tunings are outputs of the Arc positivity inequalities, not assumed inputs; the only caveat is an explicit low-spin spectrum restriction, which is a scope limitation rather than a circular step.

full rationale

I walked the derivation chain and found no step in which a claimed prediction reduces to an assumed input by construction. The Majorana tunings h2/M^6 = 1/(m^4 M_P^2), h3/M^6 = -3/(2 m^4 M_P^2), Eq. (3.18), are the unique nontrivial way to satisfy the positivity conditions in Eq. (3.17); they are not imposed beforehand. The 'decay constant' identification F^2 = 3 m^2 M_P^2, Eq. (3.21), is assigned only after the s^2 coefficient 1/(3 m^2 M_P^2) has been fixed by positivity, so the SUSY-looking relation is an output, not an input. Likewise, the Dirac result q^2 e^2/m^2 = 1/(2 M_P^2), Eq. (4.12), follows from requiring the elastic Arc in Eq. (4.11) to be non-negative, and the g = 2 result follows from positivity forcing c2 = 0 in Eq. (4.13); neither relation is put in by hand. The t-u symmetric dispersion relations of Section 5 are genuinely new sum rules derived from crossing, analyticity, and unitarity, and the Goldstino EFT-hedron bounds on g2,0 and g2,1 are consequences of those sum rules and null constraints, not restatements of the Wilson coefficients. There is a same-author citation, Ref. [23], for the Arc method, but the bounds used here are re-derived in Appendix B, and the gravitational Regge boundedness needed when gravitons are present is cited to the external Ref. [92]; thus the self-citation is not load-bearing. The one genuine weakness is the spectrum restriction stated in Section 2.1, Step 4: the proof is carried out only for light spin-0, spin-1, and one massless spin-2 particle. Section 5.4 exhibits infinite higher-spin Goldstino models (the s/tu models and Lovelace-Shapiro amplitudes, Eqs. (5.47), (5.50), (5.51)) that satisfy the Goldstino-sector positivity and null constraints, and the paper itself calls them 'models' rather than UV completions. This means the unrestricted claim that gravity is necessary is broader than what the low-spin no-go theorem establishes, and the finite-mass bounds are checked explicitly only for the isolated Majorana case (Appendix B.4). These are correctness/scope caveats, however, not circular reasoning: they identify an unproven assumption, not an equivalence between the conclusion and the input. Overall circularity is therefore minimal.

Assumptions & free parameters 2 free parameters · 7 assumptions · 0 invented entities

No numbers are fitted to data; the paper constrains ratios of Wilson coefficients. The two entries below are choices made in the analysis, not fitted parameters. The axioms are the physical and methodological assumptions listed.

free parameters (2)
  • EFT contact-interaction scale M
    Dimensionful scale in the contact terms (e.g., Eq. 3.1); assumed M >= Lambda. Positivity constrains ratios of Wilson coefficients, not the absolute scale, so the central claims are scale-independent.
  • Evaluation point t = -Lambda^2/10 = t = -Lambda^2/10
    Used to extract the numerical bound Lambda < 8.2m for the isolated Majorana case (Appendix B.4, Figs. 2,6,7). The authors state this gives a conservative upper bound; the exact coefficient depends on this choice.
assumptions (7)
  • standard math S-matrix analyticity, crossing symmetry, unitarity, and polynomial boundedness (Froissart-type)
    These are the standard pillars of the positivity bounds used throughout; they are stated in Appendix B.1.
  • domain assumption Weak coupling and large scale separation (Lambda >> m)
    Assumed in Section 2; allows neglect of IR cuts and justifies expanding in m/E.
  • ad hoc to paper The extra light spectrum is restricted to spin-0, spin-1, and one massless spin-2 particle
    Section 2.1 step 4 and Section 3.3; this is what makes the 'gravity is necessary' conclusion hold.
  • ad hoc to paper Validity of the decoupling limit m->0, M_P->infinity at fixed F = 3 m^2 M_P^2
    Used in Sections 3.2 and 4.2.1 to apply positivity in the presence of gravitons; finite-mass corrections are only estimated as O(m/Lambda).
  • domain assumption Gravitational Regge boundedness
    Invoked in Appendix B.1 via reference [92] to justify polynomial boundedness when gravitons are present.
  • domain assumption CP invariance, and separately C and P invariance where stated
    Assumed in Section 2.2; the authors argue CP-violating interactions can be treated similarly and do not change conclusions.
  • domain assumption Tree-level approximation for the Goldstino EFT-hedron and neglect of IR cuts
    Section 5.2; the sum rules for g1,0, g2,0, g2,1 are robust to loops as noted, but the higher-coefficient bounds are tree-level.

how reviews work

0 comments
Cite this review

Pith. "Pith review of (Super)$\,$Gravity from Positivity." pith.science (2026). https://pith.science/paper/6CIKON2M

@misc{pith2026250712535,
  author       = {Pith},
  title        = {Pith review of: (Super)$\,$Gravity from Positivity},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/6CIKON2M}},
  note         = {Machine review of arXiv:2507.12535}
}
abstract

We investigate whether the effective theory for isolated, massive, and weakly interacting spin-$3/2$ particles is compatible with causality and unitarity-i.e., the positivity of scattering amplitudes. We find no solution to positivity constraints, except when gravitons are also present and couple in a (nearly) supersymmetric way. Gravity is thus bootstrapped from $S$-matrix consistency conditions for the longitudinal and transverse polarizations of massive spin-$3/2$ states. For two such particles forming a $U(1)$-charged state, a (gravi)photon gauging the symmetry is also required, with couplings characteristic of supergravity and consistent with both the no global symmetry and weak gravity conjectures. We further explore the EFT-hedron associated with the longitudinal polarizations, the Goldstinos, through novel $t$-$u$ symmetric dispersion relations. We identify the extremal UV models that lie at the corners of the allowed parameter space, recovering familiar models of supersymmetry breaking and uncovering new ones.

Figures

Figures reproduced from arXiv: 2507.12535 by the authors.

Figure 1
Figure 1. Integration contour Clow in the complex-s plane, enclosing subtraction, dynamical, kine￾matical poles (red crosses) and possibly kinematical branch cuts. We are neglecting IR branch-cuts (in red), based on the weak coupling assumption, so that the integration can be deformed to a UV contour (in grey). On the one hand, Arcs can be computed within the EFT in terms of Wilson coefficients, depending then on infrared (IR… view at source ↗
Figure 2
Figure 2. Constraints on h1, h2 and h3 from positivity bounds at finite mass m, evaluated at t = −Λ 2/10 with Λ = 6m, 8m, 10m (from left to right). The blue, orange and green bands correspond to bounding |A− 1 2 − 1 2 − 1 2 − 1 2 (t, 0)|, |A+ 1 2 + 1 2 − 1 2 − 1 2 (t, 0)+A + 1 2 − 1 2 − 1 2 + 1 2 (t, 0)| and |A+ 1 2 + 1 2 − 1 2 − 1 2 (t, 0)−A+ 1 2 − 1 2 − 1 2 + 1 2 (t, 0)|. The intersection region, when present, is indicated … view at source ↗
Figure 3
Figure 3. Scheme of the contour integrals appearing in the definition of the Arcs used in this section, [PITH_FULL_IMAGE:figures/full_fig_p024_3.png] view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: Allowed regions for the normalised Wilson coefficients ˜g [PITH_FULL_IMAGE:figures/full_fig_p029_4.png]
Figure 5
Figure 5. Figure 5: Zooming in the higher-spin UV model portion of Fig. [PITH_FULL_IMAGE:figures/full_fig_p031_5.png]
Figure 6
Figure 6. Figure 6: Region of parameter space allowed by the constraints in Eq. ( [PITH_FULL_IMAGE:figures/full_fig_p040_6.png]
Figure 7
Figure 7. Figure 7: Plot of the area S of the allowed region in parameter space as a function of Λ/m, with t = −Λ 2/10. 40 [PITH_FULL_IMAGE:figures/full_fig_p040_7.png]

Discussion (0). Sign in to comment.

Forward citations

Cited by 13 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Positivity in Massive Spin-3/2 EFTs and the Planck-Suppressed Neighbourhood of Supergravity

    hep-th 2026-05 unverdicted novelty 8.0 of 10

    Massive spin-3/2 EFT contact couplings are constrained by positivity to a Planck-suppressed neighborhood of supergravity values whose volume scales as m^6/M_Pl^6 and vanishes as m approaches zero.

  2. Bootstrapping Pion Form Factors at Large $N$

    hep-th 2026-06 unverdicted novelty 7.0 of 10

    Bootstrap analysis of meromorphic observables in large-N QCD yields universal and SVZ-type bounds that constrain chiral Lagrangian parameters and link hadronic data to asymptotic freedom.

  3. Decaying spin-3/2 dark matter from baryon number violation

    hep-ph 2026-05 unverdicted novelty 7.0 of 10

    Non-supersymmetric spin-3/2 dark matter with baryon-violating portals can explain the relic abundance through UV and Boltzmann-suppressed freeze-in, with viable parameter space constrained by indirect detection, direc...

  4. Consistent Scattering Amplitudes, Yang-Mills, the Higgs Mechanism and the EFTs Beyond

    hep-th 2026-05 unverdicted novelty 7.0 of 10

    S-matrix consistency forces the complete gluon amplitude structure and requires Yang-Mills Lie algebra plus Higgs mechanism for unitarised massive vector boson scattering.

  5. Negative running of gravitational positivity

    hep-th 2026-03 unverdicted novelty 7.0 of 10

    Non-minimal three-point interactions induce negative one-loop running of Wilson coefficients in gravitational EFTs, yet graviton loops generate positive IR contributions that dominate the bounds after smearing if the ...

  6. Positivity with Long-Range Interactions

    hep-th 2025-12 unverdicted novelty 7.0 of 10

    Defines IR-finite amplitudes M_E that preserve analyticity and unitarity to derive positivity bounds on EFTs including electromagnetism and gravity in D=4.

  7. Strings from Almost Nothing

    hep-th 2025-08 conditional novelty 7.0 of 10

    Ultrasoft, minimally structured scattering amplitudes are forced onto the Veneziano and Virasoro-Shapiro amplitudes of string theory.

  8. A Dispersive Bootstrap for the Virasoro-Shapiro Amplitude

    hep-th 2026-06 unverdicted novelty 6.0 of 10

    Dispersive bootstrap with unitarity, crossing and a Virasoro-inspired ansatz isolates the Virasoro-Shapiro amplitude in a small island for the gravity-pole-subtracted four-point amplitude in 10D supersymmetry.

  9. Multipositivity Constrains the Chiral Lagrangian

    hep-th 2026-05 unverdicted novelty 6.0 of 10

    Multipositivity bounds derived from planar tree-level scattering amplitudes constrain Wilson coefficients of the chiral Lagrangian from below by the chiral anomaly.

  10. The Equivalence Principle at High Energies Completes the Spectrum

    hep-th 2026-05 unverdicted novelty 6.0 of 10

    Tree-level gravitational scattering under the equivalence principle mandates single-particle states in all irreducible representations constructible from a single seed charge, with equal interaction strengths.

  11. Positivity in Massive Spin-3/2 EFTs and the Planck-Suppressed Neighbourhood of Supergravity

    hep-th 2026-05 unverdicted novelty 6.0 of 10

    Positivity bounds on massive spin-3/2 four-fermion operators restrict the couplings to a bounded region around supergravity values whose volume scales as m^6/M_Pl^6 and vanishes as m approaches zero.

  12. Sampling the Graviton Pole and Deprojecting the Swampland

    hep-th 2026-04 unverdicted novelty 6.0 of 10

    A sampling-based bootstrap for graviton poles in EFTs yields non-projective bounds that fix the EFT cutoff scale relative to the Planck mass, with M/M_P ≲ 7.8 in D=5.

  13. The Rise of Linear Trajectories

    hep-th 2025-10 conditional novelty 6.0 of 10

    Numerical S-matrix bootstrap shows that maximized couplings of the second and third higher-spin resonances select spectra lying on a linear Regge trajectory, anchored by the graviton in gravitational theories.

Reference graph

Works this paper leans on

93 extracted references · 6 canonical work pages · cited by 12 Pith papers

  1. [23]

    Massive gravity is not positive,

    B. Bellazzini, G. Isabella, S. Ricossa, and F. Riva, “Massive gravity is not positive,” Phys. Rev. D 109 (2024), no. 2 024051, 2304.02550

  2. [1]

    Causality, analyticity and an IR obstruction to UV completion,

    A. Adams, N. Arkani-Hamed, S. Dubovsky, A. Nicolis, and R. Rattazzi, “Causality, analyticity and an IR obstruction to UV completion,” JHEP 10 (2006) 014, hep-th/0602178

  3. [2]

    Causality Constraints on Corrections to the Graviton Three-Point Coupling,

    X. O. Camanho, J. D. Edelstein, J. Maldacena, and A. Zhiboedov, “Causality Constraints on Corrections to the Graviton Three-Point Coupling,” JHEP 02 (2016) 020, 1407.5597

  4. [3]

    Symmetries, Sum Rules and Constraints on Effective Field Theories,

    B. Bellazzini, L. Martucci, and R. Torre, “Symmetries, Sum Rules and Constraints on Effective Field Theories,” JHEP 09 (2014) 100, 1405.2960

  5. [4]

    Quantum Gravity Constraints from Unitarity and Analyticity,

    B. Bellazzini, C. Cheung, and G. N. Remmen, “Quantum Gravity Constraints from Unitarity and Analyticity,” Phys. Rev. D 93 (2016), no. 6 064076, 1509.00851

  6. [5]

    Softness and amplitudes’ positivity for spinning particles,

    B. Bellazzini, “Softness and amplitudes’ positivity for spinning particles,” JHEP 02 (2017) 034, 1605.06111

  7. [6]

    Positivity bounds for scalar field theories,

    C. de Rham, S. Melville, A. J. Tolley, and S.-Y. Zhou, “Positivity bounds for scalar field theories,” Phys. Rev. D 96 (2017), no. 8 081702, 1702.06134. 48

  8. [7]

    Massive Higher Spins: Effective Theory and Consistency,

    B. Bellazzini, F. Riva, J. Serra, and F. Sgarlata, “Massive Higher Spins: Effective Theory and Consistency,” JHEP 10 (2019) 189, 1903.08664

Show all 93 references
  1. [8]

    The ˆH-Parameter: An Oblique Higgs View,

    C. Englert, G. F. Giudice, A. Greljo, and M. Mccullough, “The ˆH-Parameter: An Oblique Higgs View,” JHEP 09 (2019) 041, 1903.07725

  2. [9]

    Positive moments for scattering amplitudes,

    B. Bellazzini, J. Elias Mir´ o, R. Rattazzi, M. Riembau, and F. Riva, “Positive moments for scattering amplitudes,” Phys. Rev. D 104 (2021), no. 3 036006, 2011.00037

  3. [10]

    The EFT-Hedron,

    N. Arkani-Hamed, T.-C. Huang, and Y.-t. Huang, “The EFT-Hedron,” JHEP 05 (2021) 259, 2012.15849

  4. [11]

    Extremal Effective Field Theories,

    S. Caron-Huot and V. Van Duong, “Extremal Effective Field Theories,” JHEP 05 (2021) 280, 2011.02957

  5. [12]

    New positivity bounds from full crossing symmetry,

    A. J. Tolley, Z.-Y. Wang, and S.-Y. Zhou, “New positivity bounds from full crossing symmetry,” JHEP 05 (2021) 255, 2011.02400

  6. [13]

    Gravitational effective field theory islands, low-spin dominance, and the four-graviton amplitude,

    Z. Bern, D. Kosmopoulos, and A. Zhiboedov, “Gravitational effective field theory islands, low-spin dominance, and the four-graviton amplitude,” J. Phys. A 54 (2021), no. 34 344002, 2103.12728

  7. [14]

    Into the EFThedron and UV constraints from IR consistency,

    L.-Y. Chiang, Y.-t. Huang, W. Li, L. Rodina, and H.-C. Weng, “Into the EFThedron and UV constraints from IR consistency,” JHEP 03 (2022) 063, 2105.02862

  8. [15]

    Sharp boundaries for the swampland,

    S. Caron-Huot, D. Mazac, L. Rastelli, and D. Simmons-Duffin, “Sharp boundaries for the swampland,” JHEP 07 (2021) 110, 2102.08951

  9. [16]

    Natural selection rules: new positivity bounds for massive spinning particles,

    J. Davighi, S. Melville, and T. You, “Natural selection rules: new positivity bounds for massive spinning particles,” JHEP 02 (2022) 167, 2108.06334

  10. [17]

    Causality constraints on black holes beyond GR,

    F. Serra, J. Serra, E. Trincherini, and L. G. Trombetta, “Causality constraints on black holes beyond GR,” JHEP 08 (2022) 157, 2205.08551

  11. [18]

    Classical vs quantum eikonal scattering and its causal structure,

    B. Bellazzini, G. Isabella, and M. M. Riva, “Classical vs quantum eikonal scattering and its causal structure,” JHEP 04 (2023) 023, 2211.00085

  12. [19]

    Causality constraints on corrections to Einstein gravity,

    S. Caron-Huot, Y.-Z. Li, J. Parra-Martinez, and D. Simmons-Duffin, “Causality constraints on corrections to Einstein gravity,” JHEP 05 (2023) 122, 2201.06602

  13. [20]

    Where is M-theory in the space of scattering amplitudes?,

    A. Guerrieri, H. Murali, J. Penedones, and P. Vieira, “Where is M-theory in the space of scattering amplitudes?,” JHEP 06 (2023) 064, 2212.00151

  14. [21]

    Bounding violations of the weak gravity conjecture,

    J. Henriksson, B. McPeak, F. Russo, and A. Vichi, “Bounding violations of the weak gravity conjecture,” JHEP 08 (2022) 184, 2203.08164

  15. [22]

    Bounds on photon scattering,

    K. H¨ aring, A. Hebbar, D. Karateev, M. Meineri, and J. Penedones, “Bounds on photon scattering,” JHEP 10 (2024) 103, 2211.05795

  16. [24]

    Trace anomalies and the graviton-dilaton amplitude,

    D. Karateev, Z. Komargodski, J. Penedones, and B. Sahoo, “Trace anomalies and the graviton-dilaton amplitude,” JHEP 11 (2024) 067, 2312.09308. 49

  17. [25]

    The stringy S-matrix bootstrap: maximal spin and superpolynomial softness,

    K. H¨ aring and A. Zhiboedov, “The stringy S-matrix bootstrap: maximal spin and superpolynomial softness,” JHEP 10 (2024) 075, 2311.13631

  18. [26]

    Boundaries of universal theories,

    M. McCullough, M. Riembau, and L. Ricci, “Boundaries of universal theories,” Phys. Rev. D 111 (2025), no. 1 015031, 2312.03834

  19. [27]

    Bootstrapping the chiral anomaly at large N c,

    T. Ma, A. Pomarol, and F. Sciotti, “Bootstrapping the chiral anomaly at large N c,” JHEP 11 (2023) 176, 2307.04729

  20. [28]

    Extremal Higgs couplings,

    J. Elias Miro, A. L. Guerrieri, and M. A. Gumus, “Extremal Higgs couplings,” Phys. Rev. D 110 (2024), no. 1 016007, 2311.09283

  21. [29]

    Bootstrapping Extremal Scalar Amplitudes With and Without Supersymmetry,

    J. Berman, H. Elvang, N. Geiser, and L. L. Lin, “Bootstrapping Extremal Scalar Amplitudes With and Without Supersymmetry,” 2412.13368

  22. [30]

    Positivity bounds on electromagnetic properties of media,

    P. Creminelli, O. Janssen, B. Salehian, and L. Senatore, “Positivity bounds on electromagnetic properties of media,” JHEP 08 (2024) 066, 2405.09614

  23. [31]

    Bootstrapping the chiral-gravitational anomaly,

    Z.-Y. Dong, T. Ma, A. Pomarol, and F. Sciotti, “Bootstrapping the chiral-gravitational anomaly,” JHEP 05 (2025) 114, 2411.14422

  24. [32]

    Positivity bounds on massive vectors,

    F. Bertucci, J. Henriksson, B. McPeak, S. Ricossa, F. Riva, and A. Vichi, “Positivity bounds on massive vectors,” JHEP 12 (2024) 051, 2402.13327

  25. [33]

    Causality bounds from charged shockwaves in 5d,

    S. Cremonini, B. McPeak, M. Moezzi, and M. Rajaguru, “Causality bounds from charged shockwaves in 5d,” 2412.06891

  26. [34]

    Multipositivity Bounds,

    C. Cheung and G. N. Remmen, “Multipositivity Bounds,” 2505.05553

  27. [35]

    Primal S-matrix bootstrap with dispersion relations,

    C. de Rham, A. J. Tolley, Z.-H. Wang, and S.-Y. Zhou, “Primal S-matrix bootstrap with dispersion relations,” 2506.22546

  28. [36]

    Running EFT-hedron with null constraints at loop level,

    G. Peng, L.-Q. Shao, A. Tokareva, and Y. Xu, “Running EFT-hedron with null constraints at loop level,” 2501.09717

  29. [37]

    Graviton loops and negativity,

    C.-H. Chang and J. Parra-Martinez, “Graviton loops and negativity,” 2501.17949

  30. [38]

    Microcausality without Lorentz invariance,

    L. Hui, A. Nicolis, A. Podo, and S. Zhou, “Microcausality without Lorentz invariance,” 2502.04215

  31. [39]

    Cross-Section Bootstrap: Unveiling the Froissart Amplitude,

    M. Correia, A. Georgoudis, and A. L. Guerrieri, “Cross-Section Bootstrap: Unveiling the Froissart Amplitude,” 2506.04313

  32. [40]

    IR side of positivity bounds,

    B. Bellazzini, M. Riembau, and F. Riva, “IR side of positivity bounds,” Phys. Rev. D 106 (2022), no. 10 105008, 2112.12561

  33. [41]

    Non-Forward UV/IR Relations,

    C. Beadle, G. Isabella, D. Perrone, S. Ricossa, F. Riva, and F. Serra, “Non-Forward UV/IR Relations,” 2407.02346

  34. [42]

    The EFT Bootstrap at Finite MP L,

    C. Beadle, G. Isabella, D. Perrone, S. Ricossa, F. Riva, and F. Serra, “The EFT Bootstrap at Finite MP L,” 2501.18465

  35. [43]

    Positivity bounds in the Standard Model effective field theory beyond tree level,

    M. Chala and J. Santiago, “Positivity bounds in the Standard Model effective field theory beyond tree level,” 2110.01624. 50

  36. [44]

    Scattering amplitudes for all masses and spins,

    N. Arkani-Hamed, T.-C. Huang, and Y.-t. Huang, “Scattering amplitudes for all masses and spins,” JHEP 11 (2021) 070, 1709.04891

  37. [45]

    Direct proof of tree-level recursion relation in Yang-Mills theory,

    R. Britto, F. Cachazo, B. Feng, and E. Witten, “Direct proof of tree-level recursion relation in Yang-Mills theory,” Phys. Rev. Lett. 94 (2005) 181602, hep-th/0501052

  38. [46]

    Effective interactions and on-shell recursion relation for massive spin 3/2,

    T. Gherghetta and W. Ke, “Effective interactions and on-shell recursion relation for massive spin 3/2,” JHEP 04 (2025) 014, 2408.16065

  39. [47]

    On-shell recursion relations for higher-spin Compton amplitudes,

    Y. Ema, T. Gao, W. Ke, Z. Liu, and I. Mahbub, “On-shell recursion relations for higher-spin Compton amplitudes,” 2506.02106

  40. [48]

    Constructing massive on-shell contact terms,

    G. Durieux, T. Kitahara, C. S. Machado, Y. Shadmi, and Y. Weiss, “Constructing massive on-shell contact terms,” JHEP 12 (2020) 175, 2008.09652

  41. [49]

    Constructing on-shell operator basis for all masses and spins,

    Z.-Y. Dong, T. Ma, and J. Shu, “Constructing on-shell operator basis for all masses and spins,” Phys. Rev. D 107 (2023), no. 11 L111901, 2103.15837

  42. [50]

    Constructing generic effective field theory for all masses and spins,

    Z.-Y. Dong, T. Ma, J. Shu, and Y.-H. Zheng, “Constructing generic effective field theory for all masses and spins,” Phys. Rev. D 106 (2022), no. 11 116010, 2202.08350

  43. [51]

    Amplitude bases in generic EFTs,

    S. De Angelis, “Amplitude bases in generic EFTs,” JHEP 08 (2022) 299, 2202.02681

  44. [52]

    UV Constraints on Massive Spinning Particles: Lessons from the Gravitino,

    S. Melville, D. Roest, and D. Stefanyszyn, “UV Constraints on Massive Spinning Particles: Lessons from the Gravitino,” JHEP 02 (2020) 185, 1911.03126

  45. [53]

    The simplest massive S-matrix: from minimal coupling to Black Holes,

    M.-Z. Chung, Y.-T. Huang, J.-W. Kim, and S. Lee, “The simplest massive S-matrix: from minimal coupling to Black Holes,” JHEP 04 (2019) 156, 1812.08752

  46. [54]

    Soft Matters, or the Recursions with Massive Spinors,

    A. Falkowski and C. S. Machado, “Soft Matters, or the Recursions with Massive Spinors,” JHEP 05 (2021) 238, 2005.08981

  47. [55]

    Generalization of the Massive Scalar Multiplet Coupling to the Supergravity,

    J. Polonyi, “Generalization of the Massive Scalar Multiplet Coupling to the Supergravity,”

  48. [56]

    The String landscape and the swampland,

    C. Vafa, “The String landscape and the swampland,” hep-th/0509212

  49. [57]

    On the Geometry of the String Landscape and the Swampland,

    H. Ooguri and C. Vafa, “On the Geometry of the String Landscape and the Swampland,” Nucl. Phys. B 766 (2007) 21–33, hep-th/0605264

  50. [58]

    Symmetries and Strings in Field Theory and Gravity,

    T. Banks and N. Seiberg, “Symmetries and Strings in Field Theory and Gravity,” Phys. Rev. D 83 (2011) 084019, 1011.5120

  51. [59]

    Symmetries in quantum field theory and quantum gravity,

    D. Harlow and H. Ooguri, “Symmetries in quantum field theory and quantum gravity,” Commun. Math. Phys. 383 (2021), no. 3 1669–1804, 1810.05338

  52. [60]

    The Swampland: Introduction and Review,

    E. Palti, “The Swampland: Introduction and Review,” Fortsch. Phys. 67 (2019), no. 6 1900037, 1903.06239

  53. [61]

    The String landscape, black holes and gravity as the weakest force,

    N. Arkani-Hamed, L. Motl, A. Nicolis, and C. Vafa, “The String landscape, black holes and gravity as the weakest force,” JHEP 06 (2007) 060, hep-th/0601001

  54. [62]

    Gauge Internal Symmetry in Extended Supergravity,

    D. Z. Freedman and A. K. Das, “Gauge Internal Symmetry in Extended Supergravity,” Nucl. Phys. B 120 (1977) 221–230. 51

  55. [63]

    Consistent Supergravity with Complex Spin 3/2 Gauge Fields,

    S. Ferrara and P. van Nieuwenhuizen, “Consistent Supergravity with Complex Spin 3/2 Gauge Fields,” Phys. Rev. Lett. 37 (1976) 1669

  56. [64]

    Inconsistencies of massive charged gravitating higher spins,

    S. Deser and A. Waldron, “Inconsistencies of massive charged gravitating higher spins,” Nucl. Phys. B 631 (2002) 369–387, hep-th/0112182

  57. [65]

    S. D. Deser, M. T. Grisaru, and H. Pendleton, eds., Proceedings, 13th Brandeis University Summer Institute in Theoretical Physics, Lectures On Elementary Particles and Quantum Field Theory: Waltham, MA, USA, June 15 - July 24 1970 , (Cambridge, MA, USA), MIT, 1970

  58. [66]

    g = 2 as the natural value of the tree-level gyromagnetic ratio of elementary particles,

    S. Ferrara, M. Porrati, and V. L. Telegdi, “ g = 2 as the natural value of the tree-level gyromagnetic ratio of elementary particles,” Phys. Rev. D 46 (1992) 3529–3537

  59. [67]

    Massive spin 3/2 electrodynamics,

    S. Deser, V. Pascalutsa, and A. Waldron, “Massive spin 3/2 electrodynamics,” Phys. Rev. D 62 (2000) 105031, hep-th/0003011

  60. [68]

    Compton black-hole scattering for s ≤ 5/2,

    M. Chiodaroli, H. Johansson, and P. Pichini, “Compton black-hole scattering for s ≤ 5/2,” JHEP 02 (2022) 156, 2107.14779

  61. [69]

    Propagation and quantization of Rarita-Schwinger waves in an external electromagnetic potential,

    G. Velo and D. Zwanziger, “Propagation and quantization of Rarita-Schwinger waves in an external electromagnetic potential,” Phys. Rev. 186 (1969) 1337–1341

  62. [70]

    Causal Propagation of a Charged Spin 3/2 Field in an External Electromagnetic Background,

    M. Porrati and R. Rahman, “Causal Propagation of a Charged Spin 3/2 Field in an External Electromagnetic Background,” Phys. Rev. D 80 (2009) 025009, 0906.1432

  63. [71]

    Charged massive spin 2 and 3/2 propagation in a constant electromagnetic background,

    K. Benakli, W. Ke, and B. Le Floch, “Charged massive spin 2 and 3/2 propagation in a constant electromagnetic background,” PoS CORFU2023 (2024) 222, 2406.09213

  64. [72]

    Crossing Symmetric Dispersion Relations in Quantum Field Theories,

    A. Sinha and A. Zahed, “Crossing Symmetric Dispersion Relations in Quantum Field Theories,” Phys. Rev. Lett. 126 (2021), no. 18 181601, 2012.04877

  65. [73]

    Effective field theory bootstrap, large-N χPT and holographic QCD,

    Y.-Z. Li, “Effective field theory bootstrap, large-N χPT and holographic QCD,” JHEP 01 (2024) 072, 2310.09698

  66. [74]

    Analytic Bounds on the Spectrum of Crossing Symmetric S-Matrices,

    J. Berman, “Analytic Bounds on the Spectrum of Crossing Symmetric S-Matrices,” 2410.01914

  67. [75]

    A Semidefinite Program Solver for the Conformal Bootstrap,

    D. Simmons-Duffin, “A Semidefinite Program Solver for the Conformal Bootstrap,” JHEP 06 (2015) 174, 1502.02033

  68. [76]

    Bootstrapping pions at large N,

    J. Albert and L. Rastelli, “Bootstrapping pions at large N,” JHEP 08 (2022) 151, 2203.11950

  69. [77]

    Cornering large-N c QCD with positivity bounds,

    C. Fernandez, A. Pomarol, F. Riva, and F. Sciotti, “Cornering large-N c QCD with positivity bounds,” JHEP 06 (2023) 094, 2211.12488

  70. [78]

    Spontaneous Symmetry Breaking for Chiral Scalar Superfields,

    L. O’Raifeartaigh, “Spontaneous Symmetry Breaking for Chiral Scalar Superfields,” Nucl. Phys. B 96 (1975) 331–352

  71. [79]

    Spontaneously Broken Supergauge Symmetries and Goldstone Spinors,

    P. Fayet and J. Iliopoulos, “Spontaneously Broken Supergauge Symmetries and Goldstone Spinors,” Phys. Lett. B 51 (1974) 461–464

  72. [80]

    A novel application of regge trajectories,

    C. Lovelace, “A novel application of regge trajectories,” Physics Letters B 28 (1968), no. 4 264–268

  73. [81]

    Narrow-resonance model with regge behavior for ππ scattering,

    J. A. Shapiro, “Narrow-resonance model with regge behavior for ππ scattering,” Phys. Rev. 179 (Mar, 1969) 1345–1353. 52

  74. [82]

    On the N-pion extension of the Lovelace-Shapiro model,

    M. Bianchi, D. Consoli, and P. Di Vecchia, “On the N-pion extension of the Lovelace-Shapiro model,” JHEP 03 (2021) 119, 2002.05419

  75. [83]

    Soft Spin 3/2 Fermions Require Gravity and Supersymmetry,

    M. T. Grisaru and H. N. Pendleton, “Soft Spin 3/2 Fermions Require Gravity and Supersymmetry,” Phys. Lett. B 67 (1977) 323–326

  76. [84]

    Consistency Conditions on the S-Matrix of Massless Particles,

    P. Benincasa and F. Cachazo, “Consistency Conditions on the S-Matrix of Massless Particles,” 0705.4305

  77. [85]

    Hint to supersymmetry from the GR vacuum,

    G. Dvali, A. Kobakhidze, and O. Sakhelashvili, “Hint to supersymmetry from the GR vacuum,” Phys. Rev. D 110 (2024), no. 8 086008, 2406.18402

  78. [86]

    Supergravity from the Bottom Up,

    T. Gherghetta and W. Ke, “Supergravity from the Bottom Up,” to appear

  79. [87]

    Present state of rigorous analytic properties of scattering amplitudes,

    G. Sommer, “Present state of rigorous analytic properties of scattering amplitudes,” Fortsch. Phys. 18 (1970) 577–688

  80. [88]

    Kinematical singularities, crossing matrix and kinematical constraints for two-body helicity amplitudes,

    G. Cohen-Tannoudji, A. Morel, and H. Navelet, “Kinematical singularities, crossing matrix and kinematical constraints for two-body helicity amplitudes,” Annals Phys. 46 (1968), no. 2 239–316

  81. [89]

    Spinning S-matrix bootstrap in 4d,

    A. Hebbar, D. Karateev, and J. Penedones, “Spinning S-matrix bootstrap in 4d,” JHEP 01 (2022) 060, 2011.11708

  82. [90]

    Asymptotic behavior and subtractions in the Mandelstam representation,

    M. Froissart, “Asymptotic behavior and subtractions in the Mandelstam representation,” Phys. Rev. 123 (1961) 1053–1057

  83. [91]

    Unitarity and high-energy behavior of scattering amplitudes,

    A. Martin, “Unitarity and high-energy behavior of scattering amplitudes,” Phys. Rev. 129 (1963) 1432–1436

  84. [92]

    Gravitational Regge bounds,

    K. H¨ aring and A. Zhiboedov, “Gravitational Regge bounds,” SciPost Phys. 16 (2024), no. 1 034, 2202.08280

  85. [93]

    Inequalities for jacobi polynomials,

    U. Haagerup and H. Schlichtkrull, “Inequalities for jacobi polynomials,” The Ramanujan Journal 33 (2014), no. 2 227–246. 53

Pith tools

Reviewed August 6, 2026 · model on record in the stance chip above.