pith. machine review for the scientific record. sign in

arxiv: 2605.02013 · v1 · submitted 2026-05-03 · ✦ hep-th

Recognition: 3 theorem links

· Lean Theorem

All DDF/lightcone two-particle decay widths up to level 8 in open bosonic string in critical dimension

Igor Pesando, Samuele Critelli

Authors on Pith no claims yet

Pith reviewed 2026-05-08 19:18 UTC · model grok-4.3

classification ✦ hep-th
keywords open bosonic stringdecay widthslightcone gaugeDDF oscillatorstwo-particle decaysRegge trajectorystring scale photon
0
0 comments X

The pith

Open bosonic string states up to level 8 show decay width ratios of order one between slowest and fastest states when tachyon channels are excluded, with all dominant modes producing a photon at string scale.

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

The paper carries out a large-scale explicit computation of every Abelian two-particle decay channel, excluding the tachyon, for open bosonic string states through level 8. It reports that the ratio of the smallest to largest decay width at each level remains order one. Dominant polarized channels always contain at least one photon, and the states built primarily from DDF A_{-1} oscillators together with some A_{-2} operators prove the most stable, lying close to the leading Regge trajectory. The work also notes that equal-time formulations admit additional surge channels involving a tachyon plus a higher-mass state, which the lightcone results omit.

Core claim

For all levels examined, the ratio between the smallest and largest two-particle decay widths (tachyon channels removed) stays of order one; the leading polarized channels invariably include at least one photon; and the most stable states are those assembled from DDF/lightcone oscillators A_{-1} and selected A_{-2}, which are close relatives of the leading Regge trajectory states.

What carries the argument

The lightcone-gauge enumeration of all polarized two-particle decay amplitudes using DDF oscillators, performed level by level up to eight.

If this is right

  • States near the leading Regge trajectory remain among the most stable at every level checked.
  • Every massive open string ultimately decays into a photon carrying energy comparable to the string scale.
  • The top five polarized channels already account for roughly sixty percent of the total width, while the first hundred or so channels capture nearly all of it.
  • The order-one spread in widths persists uniformly from level two through level eight.

Where Pith is reading between the lines

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

  • If the hypothesized surges dominate once tachyons are restored, the reported lightcone widths would underestimate actual lifetimes by a large factor.
  • Stability in bosonic string theory may therefore be controlled by tachyon production rather than by the photon channels visible in the present calculation.
  • Repeating the enumeration at higher levels or with non-Abelian final states would test whether the order-one width ratio survives.

Load-bearing premise

The lightcone computation with tachyon channels removed still captures the dominant decay physics even though equal-time formulations contain additional surge channels.

What would settle it

An explicit inclusion of tachyon-plus-higher-mass channels that shifts the width ratio between slowest and fastest states by more than an order of magnitude or removes photons from the dominant channels.

Figures

Figures reproduced from arXiv: 2605.02013 by Igor Pesando, Samuele Critelli.

Figure 1
Figure 1. Figure 1: 2. All DDF/lightcone states seem to exhibit increasingly similar total decay widths (excluding tachyons), in the sense that the ratio between the fastest- and slowest-decaying states approaches 1; see view at source ↗
Figure 1
Figure 1. Figure 1: We plot for any level N ≤ 8 the log10 of the total decay width divided by 4e −2ϕ0 = g 2 o ... for the most stable and less stable states. 1 1.01 1.02 1.03 1.04 1.05 1.06 1.07 2 3 4 5 6 7 8 ratio level ratio Less stable vs Most stable partial widths foreach level view at source ↗
Figure 2
Figure 2. Figure 2: We plot for any level the ratio between the total decay width view at source ↗
Figure 3
Figure 3. Figure 3: We plot for any level and any state the ratio between fastest decay view at source ↗
Figure 4
Figure 4. Figure 4: We plot for any level and any state the ratio between the sum view at source ↗
read the original abstract

We carry out an ``experimental analysis'' in which we explicitly compute all possible Abelian two-particle decay channels (excluding the tachyon) of open bosonic massive states up to level (8), amounting to approximately 2,000,000 cases. The aim is to develop intuition about which states are the most stable and to identify the dominant decay channels. Our results show that, for all levels considered, the ratio of decay widths between the slowest- and fastest-decaying states is of order one. In most cases, the dominant polarized decay channel accounts for at least $10\%$ of the total decay width, while the first five channels together contribute roughly 60%. Even when we sum about $10000$ polarized channels. Dominant polarized channels always involve at least one photon and all strings ultimately decay into a photon carrying energy at the string scale. The most stable states are made using the DDF/lightcone oscillators $A_{-1}$ and some $A_{-2}$ and are close relatives of the states on the leading Regge trajectory. Finally, we discuss how the computation on the lightcone differs from the equal-time computation due to ``surges'', i.e., decays into a tachyon and a higher-mass state, and we hypothesize that, in bosonic string theory, decays into tachyons constitute the dominant decay channels.

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

2 major / 3 minor

Summary. The manuscript presents an exhaustive computational survey of all Abelian two-particle decay channels (excluding tachyons) for open bosonic string massive states up to level 8 in the lightcone gauge using DDF operators, covering approximately 2,000,000 cases. It reports that the ratio of decay widths between the slowest- and fastest-decaying states is O(1) at each level, that dominant polarized channels always involve at least one photon (with the top five channels contributing ~60% of the width), and that the most stable states are constructed from A_{-1} and A_{-2} oscillators, resembling the leading Regge trajectory. The paper contrasts this with equal-time formulations, noting 'surges' (tachyon plus higher-mass state) and hypothesizing that tachyon decays dominate overall.

Significance. If the results hold, this provides a large-scale numerical dataset on bosonic string decays that offers concrete intuition on state stability and channel dominance, potentially guiding analytic work on string decay amplitudes. The explicit evaluation of ~2M cases using standard DDF operators, with no fitted parameters, is a clear strength, enabling statistical claims about O(1) width ratios and photon prevalence within the computed channels.

major comments (2)
  1. The central claims of O(1) width ratios and photon dominance are obtained from a lightcone Abelian two-particle computation that excludes all tachyon channels by construction. While the manuscript notes surges in equal-time formulations and hypothesizes tachyon dominance, no quantitative inclusion or comparison of tachyon channels is provided among the reported cases. This leaves the interpretation that non-tachyon channels capture the dominant physics (and that all strings ultimately decay to string-scale photons) as an unverified assumption.
  2. The manuscript lacks presented error estimates, numerical precision details, or sample data tables for the ~2M cases. Without these, the quantitative support for statements such as the O(1) ratio holding 'for all levels considered' and the top-five channels contributing ~60% cannot be fully assessed.
minor comments (3)
  1. A precise breakdown of the number of channels per level (rather than the aggregate ~2,000,000) would improve reproducibility and allow readers to verify the scaling.
  2. Include at least one illustrative table (e.g., for level 4 or 5) listing the top decay channels, their widths, and the resulting ratio to demonstrate the O(1) claim concretely.
  3. Clarify the exact definition of 'Abelian two-particle' channels and any polarization or momentum selection rules applied when evaluating the DDF matrix elements.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading and constructive feedback on our manuscript. We address the major comments point by point below, with clarifications on scope and offers to strengthen the presentation of results.

read point-by-point responses
  1. Referee: The central claims of O(1) width ratios and photon dominance are obtained from a lightcone Abelian two-particle computation that excludes all tachyon channels by construction. While the manuscript notes surges in equal-time formulations and hypothesizes tachyon dominance, no quantitative inclusion or comparison of tachyon channels is provided among the reported cases. This leaves the interpretation that non-tachyon channels capture the dominant physics (and that all strings ultimately decay to string-scale photons) as an unverified assumption.

    Authors: Our computation is deliberately restricted to Abelian two-particle decays excluding tachyons, as stated in the title, abstract, and section 1. The O(1) ratios, photon dominance in dominant channels, and the remark that strings ultimately decay to a string-scale photon all refer specifically to the ~2M non-tachyon channels we enumerated. The manuscript does not assert that these channels dominate the overall decay; on the contrary, it explicitly contrasts the lightcone results with equal-time formulations (where surges into tachyon plus higher-mass states appear) and hypothesizes that tachyon decays are dominant in bosonic string theory. We will revise the discussion to restate the scope of the claims more explicitly and to underscore that the tachyon-dominance statement remains a hypothesis outside the present calculation. revision: partial

  2. Referee: The manuscript lacks presented error estimates, numerical precision details, or sample data tables for the ~2M cases. Without these, the quantitative support for statements such as the O(1) ratio holding 'for all levels considered' and the top-five channels contributing ~60% cannot be fully assessed.

    Authors: All amplitudes are obtained from exact algebraic expressions involving DDF operators; the only numerical step is the evaluation of the resulting widths and ratios, performed in double-precision floating point. We will add a short subsection describing this exact algebraic origin and the floating-point precision used, together with sample tables of decay widths and channel contributions for representative states at levels 2, 4, and 6. A complete dataset of all ~2M cases can be supplied as supplementary material or on request, though printing the full tables in the main text is impractical. revision: yes

Circularity Check

0 steps flagged

No circularity: direct evaluation of matrix elements via known DDF operators

full rationale

The paper performs an exhaustive computational enumeration of ~2M explicit Abelian two-particle decay matrix elements (tachyon channels excluded) using established DDF/lightcone creation operators. All reported quantities—width ratios of order one, dominance of photon-containing channels, and stability ordering—are direct numerical outputs of these calculations with no fitted parameters, no self-referential definitions, and no load-bearing self-citations. The tachyon-surge hypothesis is presented separately as an unverified conjecture and is not used to derive or justify the computed results.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The central claim rests on the standard framework of open bosonic string theory quantized in 26 dimensions using lightcone gauge and DDF operators; no new free parameters, axioms beyond domain assumptions, or invented entities are introduced.

axioms (2)
  • domain assumption Open bosonic string theory is consistently quantized in the critical dimension of 26 spacetime dimensions.
    The title and computation are performed in the critical dimension as required for the absence of anomalies.
  • domain assumption DDF operators in the lightcone gauge provide a complete and convenient basis for constructing massive string states and computing their decay amplitudes.
    The paper relies on these operators for the explicit enumeration of all channels.

pith-pipeline@v0.9.0 · 5547 in / 1516 out tokens · 82325 ms · 2026-05-08T19:18:44.431479+00:00 · methodology

discussion (0)

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

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

  • Foundation.AlexanderDuality alexander_duality_circle_linking unclear
    ?
    unclear

    Relation between the paper passage and the cited Recognition theorem.

    We compute all decays of massive bosonic open string states up to level 8 into non tachyonic states, amounting to approximately 2·10^6 processes... We work in the critical dimension, and our results may depend sensitively on the number of non-compact dimensions.

  • Cost.FunctionalEquation washburn_uniqueness_aczel unclear
    ?
    unclear

    Relation between the paper passage and the cited Recognition theorem.

    We perform this analysis in the critical dimension using the DDF/lightcone formalism... ⟨V3| = product of standard DDF vertex operator with N[r]m,[s]n combinatorics

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Reference graph

Works this paper leans on

36 extracted references · 31 canonical work pages

  1. [1]

    Lorenzo Cornalba and Miguel S. Costa. ‘Time dependent orbifolds and string cosmology’. In:Fortsch. Phys.52 (2004), pp. 145–199.doi: 10.1002/prop.200310123. arXiv:hep-th/0310099 [hep-th]

  2. [2]

    Andersson and G

    Ben Craps. ‘Big Bang Models in String Theory’. In:Class. Quant. Grav.23 (2006), S849–S881.doi:10.1088/0264- 9381/23/21/S01. arXiv:hep-th/0605199 [hep-th]. 25

  3. [3]

    ‘On the origin of divergences in time-dependent orbifolds’

    Andrea Arduino, Riccardo Finotello and Igor Pesando. ‘On the origin of divergences in time-dependent orbifolds’. In:Eur. Phys. J. C80.5 (2020), p. 476.doi:10 . 1140 / epjc / s10052 - 020 - 8010 - y. arXiv: 2002.11306 [hep-th]

  4. [4]

    ‘Light-cone quantization of scalar field on time-dependent backgrounds’

    Andrea Arduino and Igor Pesando. ‘Light-cone quantization of scalar field on time-dependent backgrounds’. In:Eur. Phys. J. C82.7 (2022), p. 647.doi:10.1140/epjc/s10052-022-10575-8. arXiv:2203.13062 [hep-th]

  5. [5]

    ‘On the breakdown of the perturbative interaction pic- ture in Big Crunch/Big Bang or the true reason why perturbative string amplitudes on temporal orbifolds diverge’

    Igor Pesando. ‘On the breakdown of the perturbative interaction pic- ture in Big Crunch/Big Bang or the true reason why perturbative string amplitudes on temporal orbifolds diverge’. In:Eur. Phys. J. C 82.12 (2022), p. 1153.doi:10 . 1140 / epjc / s10052 - 022 - 11096 - 0. arXiv:2207.02235 [hep-th]

  6. [6]

    ‘Work in progress’

    Igor Pesando and Richard Szabo. ‘Work in progress’. In: ()

  7. [7]

    Frey et al

    Andrew R. Frey et al. ‘Gravitational waves from high temperature strings’. In:JHEP12 (2024), p. 174.doi:10.1007/JHEP12(2024)174. arXiv:2408.13803 [hep-th]

  8. [8]

    ‘Gravitational Waves in String Cosmology’

    Gonzalo Villa. ‘Gravitational Waves in String Cosmology’. PhD thesis. Department of Applied Mathematics and Theoretical Physics, Cam- bridge U., Cambridge U., May 2025.doi:10.17863/CAM.121427

  9. [9]

    Di Giacomo et al

    A. Di Giacomo et al. ‘Unitarity in dual resonance models’. In:Phys. Lett. B33 (1970), pp. 171–174.doi:10.1016/0370-2693(70)90293- 5

  10. [10]

    Neveu and Joel Scherk

    A. Neveu and Joel Scherk. ‘Parameter-free regularization of one-loop unitary dual diagram’. In:Phys. Rev. D1 (1970), pp. 2355–2359.doi: 10.1103/PhysRevD.1.2355

  11. [11]

    Fourth Order Gravity as General Relativity Plus Matter,

    Michael B. Green and G. Veneziano. ‘Average properties of dual reson- ances’. In:Phys. Lett. B36 (1971), pp. 477–479.doi:10.1016/0370- 2693(71)90534-X

  12. [12]

    ‘Scattering, Ab- sorption and Emission of Highly Excited Strings’

    Maurizio Firrotta, Elias Kiritsis and Vasilis Niarchos. ‘Scattering, Ab- sorption and Emission of Highly Excited Strings’. In:Scattering, Ab- sorption and Emission of Highly Excited Strings(July 2024). arXiv: 2407.16476 [hep-th]

  13. [13]

    ‘The Decay of Macroscopic Funda- mental Strings’

    Jin Dai and Joseph Polchinski. ‘The Decay of Macroscopic Funda- mental Strings’. In:Phys. Lett. B220 (1989), pp. 387–390.doi:10. 1016/0370-2693(89)90892-7

  14. [14]

    Juan L. Manes. ‘Emission spectrum of fundamental strings: An Al- gebraic approach’. In:Nucl. Phys. B621 (2002), pp. 37–61.doi:10. 1016/S0550-3213(01)00578-8. arXiv:hep-th/0109196. 26

  15. [15]

    ‘DDF amplitudes are lightcone amp- litudes and the naturalness of Mandelstam map’

    Dripto Biswas and Igor Pesando. ‘DDF amplitudes are lightcone amp- litudes and the naturalness of Mandelstam map’. In:DDF amplitudes are lightcone amplitudes and the naturalness of Mandelstam map(Nov. 2024). arXiv:2411.06109 [hep-th]

  16. [16]

    ‘The Reggeon Ver- tex for DDF States’

    Dripto Biswas, Raffaele Marotta and Igor Pesando. ‘The Reggeon Ver- tex for DDF States’. In:The Reggeon Vertex for DDF States(Oct. 2024). arXiv:2410.17093 [hep-th]

  17. [17]

    ‘Framed DDF operators and the general solution to Virasoro constraints’

    Dripto Biswas and Igor Pesando. ‘Framed DDF operators and the general solution to Virasoro constraints’. In:Eur. Phys. J. C84.7 (2024), p. 657.doi:10 . 1140 / epjc / s10052 - 024 - 12883 - 7. arXiv: 2402.13066 [hep-th]

  18. [18]

    Version 5.47.0

    Maxima.Maxima, a Computer Algebra System. Version 5.47.0. 2023. url:https://maxima.sourceforge.io/

  19. [19]

    ‘The bosonic string spectrum and the explicit states up to level 10 from the lightcone and the chaotic behavior of certain string amplitudes’

    Igor Pesando. ‘The bosonic string spectrum and the explicit states up to level 10 from the lightcone and the chaotic behavior of certain string amplitudes’. In: (May 2024). arXiv:2405.09987 [hep-th]

  20. [20]

    Pimentel

    Bruno Bucciotti, Felipe Figueroa and Guilherme L. Pimentel. ‘Un- raveling the spectrum of the open string’. In:Nucl. Phys. B1025 (2026), p. 117397.doi:10.1016/j.nuclphysb.2026.117397. arXiv: 2511.07524 [hep-th]

  21. [21]

    Mitchell et al

    D. Mitchell et al. ‘The Decay of Highly Excited Open Strings’. In:Nucl. Phys. B315 (1989). [Erratum: Nucl.Phys.B 322, 628–628 (1989)], pp. 1–24.doi:10.1016/0550-3213(89)90446-X

  22. [22]

    ‘The Decay Rate of the Massive Modes in Type I Superstring’

    Hidehiko Okada and Akihiko Tsuchiya. ‘The Decay Rate of the Massive Modes in Type I Superstring’. In:Phys. Lett. B232 (1989), pp. 91–95. doi:10.1016/0370-2693(89)90563-7

  23. [23]

    Gross and Vladimir Rosenhaus

    David J. Gross and Vladimir Rosenhaus. ‘Chaotic scattering of highly excited strings’. In:JHEP05 (2021), p. 048.doi:10.1007/JHEP05(2021)

  24. [24]

    arXiv:2103.15301 [hep-th]

  25. [25]

    ‘Photon emission from an excited string’

    Maurizio Firrotta and Vladimir Rosenhaus. ‘Photon emission from an excited string’. In:Photon emission from an excited string09 (2022), p. 211.doi:10.1007/JHEP09(2022)211. arXiv:2207.01641 [hep-th]

  26. [26]

    Charmousis, E.J

    Massimo Bianchi et al. ‘Measure for Chaotic Scattering Amplitudes’. In:Phys. Rev. Lett.129.26 (2022), p. 261601.doi:10.1103/PhysRevLett. 129.261601. arXiv:2207.13112 [hep-th]

  27. [27]

    ‘Transient chaos analysis of string scattering’

    Koji Hashimoto, Yoshinori Matsuo and Takuya Yoda. ‘Transient chaos analysis of string scattering’. In:JHEP11 (2022), p. 147.doi:10. 1007/JHEP11(2022)147. arXiv:2208.08380 [hep-th]. 27

  28. [28]

    ‘The chaotic emergence of thermalization in highly excited string decays’

    Maurizio Firrotta. ‘The chaotic emergence of thermalization in highly excited string decays’. In:JHEP04 (2023), p. 052.doi:10 . 1007 / JHEP04(2023)052. arXiv:2301.04069 [hep-th]

  29. [29]

    ‘Measuring chaos in string scattering pro- cesses’

    Massimo Bianchi et al. ‘Measuring chaos in string scattering pro- cesses’. In:Phys. Rev. D108.6 (2023), p. 066006.doi:10 . 1103 / PhysRevD.108.066006. arXiv:2303.17233 [hep-th]

  30. [30]

    ‘Chaotic and thermal aspects in the highly excited string S-matrix’

    Diptarka Das, Santanu Mandal and Anurag Sarkar. ‘Chaotic and thermal aspects in the highly excited string S-matrix’. In:JHEP08 (2024), p. 200.doi:10.1007/JHEP08(2024)200. arXiv:2312.02127 [hep-th]

  31. [31]

    ‘Weak chaos and mixed dynamics in the string S-matrix’

    Nikola Savi´ c and Mihailo ˇCubrovi´ c. ‘Weak chaos and mixed dynamics in the string S-matrix’. In:JHEP03 (2024), p. 101.doi:10.1007/ JHEP03(2024)101. arXiv:2401.02211 [hep-th]

  32. [32]

    ‘Veneziano and Shapiro-Virasoro amplitudes of ar- bitrarily excited strings’

    Maurizio Firrotta. ‘Veneziano and Shapiro-Virasoro amplitudes of ar- bitrarily excited strings’. In:Veneziano and Shapiro-Virasoro amp- litudes of arbitrarily excited strings(Feb. 2024). arXiv:2402.16183 [hep-th]

  33. [33]

    ‘From spectral to scattering form factor’

    Massimo Bianchi et al. ‘From spectral to scattering form factor’. In: JHEP06 (2024), p. 189.doi:10 . 1007 / JHEP06(2024 ) 189. arXiv: 2403.00713 [hep-th]

  34. [34]

    ‘Quantum chaos and complex- ity from string scattering amplitudes’

    Aranya Bhattacharya and Aneek Jana. ‘Quantum chaos and complex- ity from string scattering amplitudes’. In:Quantum chaos and com- plexity from string scattering amplitudes(Aug. 2024). arXiv:2408. 11096 [hep-th]

  35. [35]

    ‘No ”chaos” in bosonic string massive scalar amplitudes’

    Igor Pesando. ‘No ”chaos” in bosonic string massive scalar amplitudes’. In:No ”chaos” in bosonic string massive scalar amplitudes(Feb. 2025). arXiv:2502.03539 [hep-th]. A Notations Index are µ, ν= 0,1, . . . d−1 = 25, I= 1,2, . . . d−1 = 25, i= 2,3, . . . d−1 = 25 (A.1) We denote a state 25Y i=2 LiY n=1 αi −n Ni n = α2 −L2 N2L 2 α2 −L2+1 N2L 2−1 . . . α2 ...

  36. [36]

    swap canonical decay

    At the same time we have to count properly the degeneration by considering all inequivalent decays. The set of decays on which we im- pose an equivalence relation in order to determine the inequivalent decays are the decays generated by a permutation on the canonical decay and the decays generated by a permutation on the “swap canonical decay” which is ge...