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arxiv: 2606.30368 · v1 · pith:ANYJJWZEnew · submitted 2026-06-29 · ✦ hep-th

Positivity properties of observables in planar maximally supersymmetric Yang-Mills theory

Pith reviewed 2026-06-30 05:06 UTC · model grok-4.3

classification ✦ hep-th
keywords Stieltjes propertydispersion relationsN=4 SYManomalous dimensionsWilson loopBremsstrahlung functionpositivityintegrability
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0 comments X

The pith

Observables in planar N=4 SYM satisfy the Stieltjes property through integral representations over positive measures.

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

The paper investigates whether exact observables in planar N=4 super Yang-Mills, treated as functions of the 't Hooft coupling, admit once-subtracted dispersion representations with positive spectral measures. It proves this Stieltjes property analytically for the octagon anomalous dimension, the logarithm of the circular Wilson loop, the Bremsstrahlung function, and anomalous dimensions in the BMN limit by direct verification from their integral representations. Numerical evidence supports the property for the cusp and tilted cusp anomalous dimensions, while certain other quantities fail the Stieltjes test but satisfy the weaker condition of complete monotonicity. The property enables conversion of perturbative data into non-perturbative bounds and bootstrapping of series coefficients, plus recovery of strong-coupling expansions via Mellin-Barnes transforms.

Core claim

A broad class of exact observables in planar N=4 SYM possess the Stieltjes property as functions of the coupling. This is shown analytically via integral representations whose kernels or measures yield positive spectral densities, for the octagon anomalous dimension, logarithm of the circular Wilson loop, Bremsstrahlung function, and BMN-limit anomalous dimensions. Numerical checks confirm it for cusp and tilted-cusp cases. Quantities lacking the property are identified and weaker positivity is examined. The representation yields non-perturbative bounds from perturbative input, coefficient bootstrapping, and a route to strong-coupling data from weak-coupling input through Mellin-Barnes integ

What carries the argument

The Stieltjes property: the existence of a once-subtracted dispersion representation in the coupling with a positive spectral measure, verified from integral representations.

If this is right

  • Perturbative input converts directly into rigorous non-perturbative bounds on the observables.
  • Perturbative series coefficients can be bootstrapped from the positivity constraint.
  • The strong-coupling expansion including non-perturbative corrections is recoverable from the dispersion representation via a Mellin-Barnes contour integral.
  • Weak-coupling data alone can be used to estimate the strong-coupling expansion.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same integral-representation technique might be applied to test positivity in other integrable gauge theories or in limits of N=4 SYM beyond those examined.
  • Failure of the Stieltjes property for specific quantities could be linked to the presence of additional branch cuts or non-integrable singularities not captured by the once-subtracted form.
  • If the positivity holds more generally, it could constrain the possible functional forms of observables in planar theories even when full integrability is absent.

Load-bearing premise

The observables possess integral representations over the coupling whose kernels permit direct verification that the associated spectral density is positive.

What would settle it

A concrete computation showing that the spectral measure extracted from the integral representation of the octagon anomalous dimension takes negative values for some range of the coupling.

read the original abstract

We study positivity properties of exact observables in planar N=4 super Yang-Mills as functions of the 't Hooft coupling. Motivated by analogous results in quantum mechanics, we ask whether such observables admit a once-subtracted dispersion representation in the coupling over a positive spectral measure. Our main result is that this property, also known as the Stieltjes property, holds for a broad class of exact observables. We prove it analytically, through integral representations, for the octagon anomalous dimension, the logarithm of the circular Wilson loop, the Bremsstrahlung function, and anomalous dimensions in the BMN limit, and we provide numerical evidence for the cusp and tilted cusp anomalous dimensions. We also identify quantities for which the Stieltjes property does not hold, and study the weaker positivity property of complete monotonicity. The Stieltjes property yields two powerful consequences: it lets us turn perturbative input into rigorous non-perturbative bounds, and bootstrap perturbative coefficients. We also show how the strong-coupling expansion and its non-perturbative corrections can be recovered from the once-subtracted dispersion representation via a Mellin-Barnes representation and outline a method to estimate the strong-coupling expansion from weak-coupling data.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 2 minor

Summary. The manuscript claims that a broad class of exact observables in planar N=4 SYM satisfy the Stieltjes property (once-subtracted dispersion relation with positive spectral measure in the 't Hooft coupling). This is proven analytically via integral representations for the octagon anomalous dimension, logarithm of the circular Wilson loop, Bremsstrahlung function, and BMN anomalous dimensions; numerical evidence is supplied for the cusp and tilted cusp anomalous dimensions, counterexamples are identified where the property fails, and the weaker complete monotonicity property is studied. Consequences include non-perturbative bounds from perturbative data, bootstrapping of coefficients, and recovery of strong-coupling expansions via Mellin-Barnes representations.

Significance. If the central claims hold, the work is significant because it establishes positivity properties that convert perturbative series into rigorous non-perturbative bounds and enable coefficient bootstrapping in planar N=4 SYM. The analytic proofs rest on explicit integral representations whose positivity is directly verifiable, and the paper supplies both these representations and explicit counterexamples. The outlined method for estimating strong-coupling data from weak-coupling input is a concrete practical contribution.

minor comments (2)
  1. [Abstract] Abstract: the statement that numerical evidence is provided for the cusp anomalous dimensions would be strengthened by indicating the perturbative orders employed and the range of coupling values tested.
  2. The discussion of complete monotonicity for cases where the Stieltjes property fails would benefit from a short comparative table or explicit examples to clarify the distinction.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive and accurate summary of our manuscript, their assessment of its significance, and the recommendation for minor revision. No specific major comments were raised in the report.

Circularity Check

0 steps flagged

No significant circularity; derivation self-contained via independent integral representations

full rationale

The paper proves the Stieltjes property analytically by supplying explicit integral representations over the 't Hooft coupling for the octagon anomalous dimension, log of the circular Wilson loop, Bremsstrahlung function, and BMN anomalous dimensions, then directly verifying positivity of the spectral measures from the kernels. These steps are independent of fitted parameters or prior self-citations; the manuscript also supplies numerical evidence for other cases and explicit counterexamples where the property fails. The derived consequences (non-perturbative bounds, coefficient bootstrapping, strong-coupling recovery via Mellin-Barnes) follow from the established positivity without reducing to the input representations by construction. No load-bearing step collapses to a self-definition or fitted input.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on the existence of suitable integral representations for the observables that allow positivity of the spectral measure to be verified; no free parameters or invented entities are mentioned in the abstract.

axioms (1)
  • domain assumption The listed observables possess integral representations over the coupling whose kernels permit direct positivity analysis of the spectral measure.
    Invoked to prove the once-subtracted dispersion representation with positive measure.

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Works this paper leans on

77 extracted references · 4 canonical work pages

  1. [1]

    Weinberg,The Quantum theory of fields

    S. Weinberg,The Quantum theory of fields. Vol. 1: Foundations. Cambridge University Press,

  2. [2]

    10.1017/CBO9781139644167

  3. [3]

    R. J. Eden, P. V. Landshoff, D. I. Olive and J. C. Polkinghorne,The analytic S-matrix. Cambridge Univ. Press, 1966

  4. [4]

    Colangelo and A

    P. Colangelo and A. Khodjamirian,QCD sum rules, a modern perspective,hep-ph/0010175

  5. [5]

    Adams, N

    A. Adams, N. Arkani-Hamed, S. Dubovsky, A. Nicolis and R. Rattazzi,Causality, analyticity and an IR obstruction to UV completion,JHEP10(2006) 014, [hep-th/0602178]

  6. [6]

    Bellazzini, J

    B. Bellazzini, J. Elias Mir´ o, R. Rattazzi, M. Riembau and F. Riva,Positive moments for scattering amplitudes,Phys. Rev. D104(2021) 036006, [2011.00037]

  7. [7]

    Poland, S

    D. Poland, S. Rychkov and A. Vichi,The Conformal Bootstrap: Theory, Numerical Techniques, and Applications,Rev. Mod. Phys.91(2019) 015002, [1805.04405]

  8. [8]

    Kruczenski, J

    M. Kruczenski, J. Penedones and B. C. van Rees,Snowmass White Paper: S-matrix Bootstrap, 2203.02421

  9. [9]

    Ditsch, J

    S. Ditsch, J. M. Henn and P. Raman,Approximating Feynman integrals using complete monotonicity and Stieltjes properties,JHEP05(2026) 122, [2512.18499]

  10. [10]

    Arkani-Hamed and J

    N. Arkani-Hamed and J. Trnka,The Amplituhedron,JHEP10(2014) 030, [1312.2007]

  11. [11]

    Henn and P

    J. Henn and P. Raman,Positivity properties of scattering amplitudes,JHEP04(2025) 150, [2407.05755]. – 29 –

  12. [12]

    Arkani-Hamed, T.-C

    N. Arkani-Hamed, T.-C. Huang and Y.-t. Huang,The EFT-Hedron,JHEP05(2021) 259, [2012.15849]

  13. [13]

    G. V. Dunne and M. ¨Unsal,What is QFT? Resurgent trans-series, Lefschetz thimbles, and new exact saddles,PoSLATTICE2015(2016) 010, [1511.05977]

  14. [14]

    Aniceto, G

    I. Aniceto, G. Basar and R. Schiappa,A Primer on Resurgent Transseries and Their Asymptotics,Phys. Rept.809(2019) 1–135, [1802.10441]

  15. [15]

    Dorigoni,An Introduction to Resurgence, Trans-Series and Alien Calculus,Annals Phys

    D. Dorigoni,An Introduction to Resurgence, Trans-Series and Alien Calculus,Annals Phys. 409(2019) 167914, [1411.3585]

  16. [16]

    C. M. Bender and T. T. Wu,Anharmonic oscillator,Phys. Rev.184(1969) 1231–1260

  17. [17]

    Simon,Coupling constant analyticity for the anharmonic oscillator,Annals Phys.58(1970) 76–136

    B. Simon,Coupling constant analyticity for the anharmonic oscillator,Annals Phys.58(1970) 76–136

  18. [18]

    C. M. Bender and S. A. Orszag,Advanced Mathematical Methods for Scientists and Engineers I. Springer, 1999. 10.1007/978-1-4757-3069-2

  19. [19]

    G. A. Baker and P. Graves-Morris,Pad´ e Approximants. Encyclopedia of Mathematics and its Applications. Cambridge University Press, 2 ed., 1996

  20. [20]

    C. M. Bender and E. Weniger,Numerical evidence that the perturbation expansion for a nonHermitian Hamiltonian is Stieltjes,J. Math. Phys.42(2001) 2167–2183, [math-ph/0010007]

  21. [21]

    Graffi, V

    S. Graffi, V. Grecchi and B. Simon,Borel summability: Application to the anharmonic oscillator,Phys. Lett. B32(1970) 631–634

  22. [22]

    Grecchi, M

    V. Grecchi, M. Maioli and A. Martinez,Pad´ e summability of the cubic oscillator,Journal of Physics A: Mathematical and Theoretical42(oct, 2009) 425208

  23. [23]

    Beisert, B

    N. Beisert, B. Eden and M. Staudacher,Transcendentality and Crossing,J. Stat. Mech.0701 (2007) P01021, [hep-th/0610251]

  24. [24]

    Beisert et al.,Review of AdS/CFT Integrability: An Overview,Lett

    N. Beisert et al.,Review of AdS/CFT Integrability: An Overview,Lett. Math. Phys.99(2012) 3–32, [1012.3982]

  25. [25]

    Pestun,Localization of gauge theory on a four-sphere and supersymmetric Wilson loops, Commun

    V. Pestun,Localization of gauge theory on a four-sphere and supersymmetric Wilson loops, Commun. Math. Phys.313(2012) 71–129, [0712.2824]

  26. [26]

    Bajnok, B

    Z. Bajnok, B. Boldis and G. P. Korchemsky,Solving four-dimensional superconformal Yang-Mills theories with Tracy-Widom distribution,JHEP04(2025) 005, [2409.17227]

  27. [27]

    J. M. Maldacena,The LargeNlimit of superconformal field theories and supergravity,Adv. Theor. Math. Phys.2(1998) 231–252, [hep-th/9711200]

  28. [28]

    D. V. Widder,Laplace Transform. Princeton University Press, 2015. doi:10.1515/9781400876457

  29. [29]

    Schm¨ udgen,Ten lectures on the moment problem,2008.12698

    K. Schm¨ udgen,Ten lectures on the moment problem,2008.12698

  30. [30]

    Merkle,Completely monotone functions - a digest,1211.0900

    M. Merkle,Completely monotone functions - a digest,1211.0900

  31. [31]

    N. I. Akhiezer,Function theoretic methods in the moment problem, pp. 90–137. Society for Industrial and Applied Mathematics, 2020. 10.1137/1.9781611976397.ch3

  32. [32]

    Raman and A

    P. Raman and A. Sinha,QFT, EFT and GFT,JHEP12(2021) 203, [2107.06559]. – 30 –

  33. [33]

    J. L. Basdevant,The Pad´ e approximation and its physical applications,Fortsch. Phys.20 (1972) 283–331

  34. [34]

    A. M. Polyakov,Gauge Fields as Rings of Glue,Nucl. Phys. B164(1980) 171–188

  35. [35]

    G. P. Korchemsky and A. V. Radyushkin,Renormalization of the Wilson Loops Beyond the Leading Order,Nucl. Phys. B283(1987) 342–364

  36. [36]

    I. A. Korchemskaya and G. P. Korchemsky,On lightlike Wilson loops,Phys. Lett. B287 (1992) 169–175

  37. [37]

    J. C. Collins, D. E. Soper and G. F. Sterman,Factorization of Hard Processes in QCD,Adv. Ser. Direct. High Energy Phys.5(1989) 1–91, [hep-ph/0409313]

  38. [38]

    Magnea and G

    L. Magnea and G. F. Sterman,Analytic continuation of the Sudakov form-factor in QCD, Phys. Rev. D42(1990) 4222–4227

  39. [39]

    Kodaira and L

    J. Kodaira and L. Trentadue,Summing Soft Emission in QCD,Phys. Lett. B112(1982) 66

  40. [40]

    L. F. Alday and J. M. Maldacena,Comments on operators with large spin,JHEP11(2007) 019, [0708.0672]

  41. [41]

    G. P. Korchemsky,Asymptotics of the Altarelli-Parisi-Lipatov Evolution Kernels of Parton Distributions,Mod. Phys. Lett. A4(1989) 1257–1276

  42. [42]

    M. K. Benna, S. Benvenuti, I. R. Klebanov and A. Scardicchio,A Test of the AdS/CFT correspondence using high-spin operators,Phys. Rev. Lett.98(2007) 131603, [hep-th/0611135]

  43. [43]

    Basso, G

    B. Basso, G. P. Korchemsky and J. Kotanski,Cusp anomalous dimension in maximally supersymmetric Yang-Mills theory at strong coupling,Phys. Rev. Lett.100(2008) 091601, [0708.3933]

  44. [44]

    Dorigoni and Y

    D. Dorigoni and Y. Hatsuda,Resurgence of the Cusp Anomalous Dimension,JHEP09(2015) 138, [1506.03763]

  45. [45]

    Aniceto,The Resurgence of the Cusp Anomalous Dimension,J

    I. Aniceto,The Resurgence of the Cusp Anomalous Dimension,J. Phys. A49(2016) 065403, [1506.03388]

  46. [46]

    Basso, L

    B. Basso, L. J. Dixon and G. Papathanasiou,Origin of the Six-Gluon Amplitude in Planar N = 4Supersymmetric Yang-Mills Theory,Phys. Rev. Lett.124(2020) 161603, [ 2001.05460]

  47. [47]

    Basso, L

    B. Basso, L. J. Dixon, Y.-T. Liu and G. Papathanasiou,All-Orders Quadratic-Logarithmic Behavior for Amplitudes,Phys. Rev. Lett.130(2023) 111602, [2211.12555]

  48. [48]

    Basso, T

    B. Basso, T. Fleury, E. Kalu¸ c and D. Serban,Null limit of large-charge correlators in planar N= 4Super-Yang-Mills theory,2606.24018

  49. [49]

    Caron-Huot and F

    S. Caron-Huot and F. Coronado,Ten dimensional symmetry ofN= 4 SYM correlators, JHEP03(2022) 151, [2106.03892]

  50. [50]

    Kostov, V

    I. Kostov, V. B. Petkova and D. Serban,The Octagon as a Determinant,JHEP11(2019) 178, [1905.11467]

  51. [51]

    A. V. Belitsky and G. P. Korchemsky,Exact null octagon,JHEP05(2020) 070, [ 1907.13131]

  52. [52]

    Correa, J

    D. Correa, J. Henn, J. Maldacena and A. Sever,An exact formula for the radiation of a moving quark in N=4 super Yang Mills,JHEP06(2012) 048, [1202.4455]

  53. [53]

    J. K. Erickson, G. W. Semenoff and K. Zarembo,Wilson loops in N=4 supersymmetric Yang-Mills theory,Nucl. Phys. B582(2000) 155–175, [hep-th/0003055]. – 31 –

  54. [54]

    Drukker and D

    N. Drukker and D. J. Gross,An Exact prediction of N=4 SUSYM theory for string theory,J. Math. Phys.42(2001) 2896–2914, [hep-th/0010274]

  55. [55]

    A. V. Belitsky and G. P. Korchemsky,Octagon at finite coupling,JHEP07(2020) 219, [2003.01121]

  56. [56]

    A. V. Belitsky and G. P. Korchemsky,Crossing bridges with strong Szeg˝ o limit theorem,JHEP 04(2021) 257, [2006.01831]

  57. [57]

    Bajnok, B

    Z. Bajnok, B. Boldis and G. P. Korchemsky,Tracy-Widom Distribution in Four-Dimensional Supersymmetric Yang-Mills Theories,Phys. Rev. Lett.133(2024) 031601, [2403.13050]

  58. [58]

    Bajnok, B

    Z. Bajnok, B. Boldis and G. P. Korchemsky,Exploring superconformal Yang-Mills theories through matrix Bessel kernels,SciPost Phys.19(2025) 004, [2412.08732]

  59. [59]

    G. P. Korchemsky,Lattice path combinatorics in superconformal Yang-Mills theories, 2508.20901

  60. [60]

    Beccaria, G

    M. Beccaria, G. P. Korchemsky and A. A. Tseytlin,Strong coupling expansion in N = 2 superconformal theories and the Bessel kernel,JHEP09(2022) 226, [2207.11475]

  61. [61]

    Chicherin, J

    D. Chicherin, J. Drummond, P. Heslop and E. Sokatchev,All three-loop four-point correlators of half-BPS operators in planarN= 4 SYM,JHEP08(2016) 053, [1512.02926]

  62. [62]

    Coronado,Bootstrapping the Simplest Correlator in PlanarN= 4Supersymmetric Yang-Mills Theory to All Loops,Phys

    F. Coronado,Bootstrapping the Simplest Correlator in PlanarN= 4Supersymmetric Yang-Mills Theory to All Loops,Phys. Rev. Lett.124(2020) 171601, [1811.03282]

  63. [63]

    Bajnok, B

    Z. Bajnok, B. Boldis and D. le Plat,Universality in the resurgence of generalized Tracy-Widom distributions,Phys. Lett. B874(2026) 140232, [2509.20302]

  64. [64]

    Marboe and D

    C. Marboe and D. Volin,Quantum spectral curve as a tool for a perturbative quantum field theory,Nucl. Phys. B899(2015) 810–847, [1411.4758]

  65. [65]

    J. A. Minahan and K. Zarembo,The Bethe ansatz for N=4 superYang-Mills,JHEP03(2003) 013, [hep-th/0212208]

  66. [66]

    Ambjorn, R

    J. Ambjorn, R. A. Janik and C. Kristjansen,Wrapping interactions and a new source of corrections to the spin-chain/string duality,Nucl. Phys. B736(2006) 288–301, [hep-th/0510171]

  67. [67]

    Bajnok and R

    Z. Bajnok and R. A. Janik,Four-loop perturbative Konishi from strings and finite size effects for multiparticle states,Nucl. Phys. B807(2009) 625–650, [0807.0399]

  68. [68]

    Beisert and M

    N. Beisert and M. Staudacher,Long-range psu(2,2—4) Bethe Ansatze for gauge theory and strings,Nucl. Phys. B727(2005) 1–62, [hep-th/0504190]

  69. [69]

    D. E. Berenstein, J. M. Maldacena and H. S. Nastase,Strings in flat space and pp waves from N=4 superYang-Mills,JHEP04(2002) 013, [hep-th/0202021]

  70. [70]

    Plefka,Spinning strings and integrable spin chains in the AdS/CFT correspondence,Living Rev

    J. Plefka,Spinning strings and integrable spin chains in the AdS/CFT correspondence,Living Rev. Rel.8(2005) 9, [hep-th/0507136]

  71. [71]

    Arkani-Hamed, J

    N. Arkani-Hamed, J. Henn and J. Trnka,Nonperturbative negative geometries: amplitudes at strong coupling and the amplituhedron,JHEP03(2022) 108, [2112.06956]

  72. [72]

    Roiban and A

    R. Roiban and A. A. Tseytlin,Semiclassical string computation of strong-coupling corrections to dimensions of operators in Konishi multiplet,Nucl. Phys. B848(2011) 251–267, [1102.1209]. – 32 –

  73. [73]

    Z. Bern, M. Czakon, L. J. Dixon, D. A. Kosower and V. A. Smirnov,The Four-Loop Planar Amplitude and Cusp Anomalous Dimension in Maximally Supersymmetric Yang-Mills Theory, Phys. Rev. D75(2007) 085010, [hep-th/0610248]

  74. [74]

    Costin and G

    O. Costin and G. V. Dunne,Conformal and uniformizing maps in Borel analysis,Eur. Phys. J. ST230(2021) 2679–2690, [2108.01145]

  75. [75]

    L. F. Alday, E. Armanini, A. V. Belitsky, K. H¨ aring and A. Zhiboedov,Walking Sudakov: From Cusp to Octagon,2605.16034

  76. [76]

    Feller,An Introduction to Probability Theory and Its Applications, vol

    W. Feller,An Introduction to Probability Theory and Its Applications, vol. 1. Wiley, 1968

  77. [77]

    McMahon,On the roots of the Bessel and certain related functions,Annals Math.9(1895) 23–30

    J. McMahon,On the roots of the Bessel and certain related functions,Annals Math.9(1895) 23–30. – 33 –