Pith. sign in

REVIEW 4 major objections 6 minor 52 references

The Carrollian limit of bosonic supergravity stays finite once four-derivative α' corrections are included, and a power-counting rule decides which higher pure-curvature terms survive.

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

T0 review · grok-4.5

2026-07-31 05:58 UTC pith:D4Z5YQRL

load-bearing objection Solid niche extension that builds the finite Carrollian MT action and a useful Riem^N counting rule, but the two headline cancellations are asserted rather than displayed. the 4 major comments →

arxiv 2607.24916 v1 pith:D4Z5YQRL submitted 2026-07-27 hep-th

Carrollian bosonic supergravity at order α' and the universal cancellation of higher-curvature divergences

classification hep-th
keywords Carrollian geometrybosonic supergravityα'-correctionshigher-curvature termsMetsaev-Tseytlin actionultra-relativistic limitRiemann powersstring effective action
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

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

This paper shows that the ultra-relativistic (Carrollian) limit of the low-energy effective action of bosonic string theory remains finite after the four-derivative α' corrections are turned on. Apparent divergences that appear in intermediate expansions cancel exactly, without forcing a special choice of non-metricity, and the resulting finite effective action is written in covariant form under simple compatibility conditions on the Carrollian fields. The author then isolates a universal counting rule for any local invariant built from N>1 Riemann tensors: once each Riemann is finite, inverse-metric contractions supply at most w^{2N}, which is precisely cancelled by the measure and the α' rescaling, leaving a finite contribution. Applying the rule, the purely gravitational α'² and α'³ corrections are finite and are written explicitly, while the pieces proportional to ζ(3) drop out of the Carrollian theory at order α'³. A reader who cares about simplifying string theory while keeping controlled higher-curvature effects now has both an explicit four-derivative Carrollian action and a quick test for which higher-curvature sectors can be trusted in the same limit.

Core claim

The full four-derivative Metsaev–Tseytlin bosonic action admits a finite Carrollian limit: the apparent w^6 (and lower) divergences cancel without restricting the non-metricities, and under the conditions ∇_μ h_νρ = 0 and ∇_μ τ^ν = 0 the finite covariant action can be written explicitly. The same mechanism yields a universal criterion: any pure Riem_1⋯Riem_N term with leading scaling O(w^{2N}) remains finite after the measure and α'^{N−1} rescaling, so the purely gravitational α'² and α'³ corrections survive while the ζ(3) sector at α'³ does not contribute.

What carries the argument

Universal finiteness criterion for powers of the Riemann tensor: under the compatibility conditions that kill the divergent pieces of each relativistic Riemann, every Riem is O(w^0); the only positive powers of the Carrollian parameter then come from inverse-metric contractions. If the leading invariant scales as O(w^{2N}), it is exactly balanced by √−ĝ e^{−2φ̂} ∼ w^{−2} and α'^{N−1} ∼ w^{−(2N−2)}, producing an O(w^0) contribution to the action.

Load-bearing premise

The whole cancellation rests on rescaling the string length as α' = α'_C / w² together with one fixed Carrollian ansatz for the metric, B-field and dilaton; if that scaling is not the right physical one, the powers no longer cancel.

What would settle it

Expand the H-dependent four-derivative pieces or any of the pure Riem^3 / Riem^4 terms in the Carrollian parameter, keep the full set of non-metricities, and check whether a non-vanishing positive power of w survives after all index contractions; or recompute the α'³ ζ(3) sector and exhibit a finite non-zero Carrollian remainder.

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

If this is right

  • The complete four-derivative Carrollian bosonic action is now available in covariant form for dynamics and holography.
  • Purely gravitational α'² and α'³ corrections can be added without introducing new divergences.
  • Terms proportional to ζ(3) drop out of Carrollian bosonic supergravity at order α'³.
  • The same power count screens higher-curvature sectors of bosonic, heterotic and Type II theories when the three-form is switched off.
  • Carrollian geometry remains compatible with stringy higher-derivative corrections beyond the two-derivative truncation.

Where Pith is reading between the lines

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

  • A T-duality covariant rewriting of the H=0 Carrollian theory at order α' may evade existing no-go results that block a manifestly dual formulation in the relativistic theory.
  • The contrast with the non-relativistic limit, where analogous divergences persist, suggests that a unified treatment of both limits at order α' will require matched field redefinitions rather than a single expansion.
  • The same criterion applied to the heterotic gravitational Green–Schwarz term could decide whether the Carrollian A_μ field must acquire higher-derivative corrections to its boost transformations.

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 6 minor

Summary. The manuscript studies the Carrollian (c→0) limit of bosonic supergravity beyond leading order. Starting from the Metsaev–Tseytlin four-derivative action (1)–(3) and the Carrollian ansatz (5)–(11) with the rescaling α′ = α′_C/w² inherited from the companion paper [22], the author claims: (i) the w⁶ divergence of the full four-derivative action, Eq. (26), cancels identically without any choice of the non-metricities (22)–(25); (ii) under the compatibility conditions ∇h = ∇τ = 0 an explicit finite covariant action (31)–(36) results; (iii) a universal counting criterion (40) establishes finiteness of pure Riem^N invariants whose leading term scales as O(w^{2N}); and (iv) the purely gravitational α′² and α′³ corrections are finite, with the ζ(3) sector at α′³ dropping out entirely, leaving the explicit result (44). The work is a natural and potentially valuable extension of [22], and the explicit finite actions are concrete deliverables. However, the two most surprising claims — the non-metricity-independent cancellation (26) and the above-threshold cancellations in the α′³ invariant (43) — are asserted in single sentences without any displayed algebra or computational verification, and the "universal criterion" is conditional on precisely the scaling property these cancellations are needed to establish.

Significance. If the results hold, this is the first demonstration that Carrollian bosonic supergravity survives α′ corrections, and the first finiteness proofs for Riem³ and Riem⁴ sectors under this limit — a genuinely useful robustness statement for the current Carrollian/stringy program. The explicit finite Lagrangians (31)–(36), (42) and (44), together with the appendix's complete f-sector, are concrete, checkable deliverables; the ζ(3) non-contribution at α′³ is a sharp, falsifiable statement; and the contrast drawn with the non-relativistic limit (§VII) is of independent interest. The paper is also honest in places about the limits of its criterion (§VI, final paragraph). The strengths are, however, currently undercut by the fact that the load-bearing cancellations are stated rather than shown: none of the three headline claims can presently be verified from the manuscript alone.

major comments (4)
  1. [§IV, Eqs. (26)–(27)] Main result 1 rests on a single sentence: 'After replacing the previous expression in (26), the divergence vanishes.' Eq. (27) contains 18 terms in unconstrained ∇τ, ∇h and ∇∇h, and the contraction (26) is claimed to vanish identically for arbitrary non-metricities satisfying only (22)–(25). This identity is the paper's central result and must be demonstrated: either display the cancellation (e.g., term-by-term using τ–h orthogonality (9)–(11) and the antisymmetrization implicit between the two lines of (26)), or provide an appendix/ancillary file with a machine-checked evaluation (xAct or similar). As written, if the identity held only modulo a further condition on the non-metricities, result 1 would collapse to the conditional version of §V, so this cannot be left to the reader.
  2. [§VI, Eqs. (40), (43)–(44)] The 'universal criterion' (40) proves finiteness only for invariants whose leading term is O(w^{2N}). But the α′³ invariant (43) violates this count: the second term in parentheses contains 8 inverse metrics ĝ^{μν} = h^{μν} − w²τ^μτ^ν, giving a naive w^{16} sector, and the first, third and fourth terms contain 6 inverse metrics (naive w^{12}), while finiteness requires I_4 = O(w^8). The above-threshold sectors must therefore vanish identically through τ–h orthogonality and Riemann antisymmetry — exactly the non-automatic step the criterion assumes. Only the surviving w^8 terms are displayed in (44). The identical vanishing of the w^{16}, w^{14}, w^{12} and w^{10} sectors of (43) must be shown for the claimed α′³ finiteness proof to go through; the α′² example (41)–(42) is fine because its count already saturates w^{2N}.
  3. [§VI, Eq. (43), ζ(3) bracket] The ζ(3) structures in (43) carry 4 inverse metrics, so their leading term sits at exactly w^8 — the finite order. Hence 'the terms proportional to ζ(3) do not contribute' is a claim of exact algebraic vanishing at finite order, not of subleading suppression, and it is one of the paper's headline statements (abstract, §II). It is currently only asserted. A short demonstration (which contractions force τ^μτ^ν pairs onto antisymmetric Riemann index pairs, or the explicit xAct output) is required.
  4. [§III, Eq. (8) and the α′ rescaling] All finiteness counts in §§IV–VI depend on α′ = α′_C/w² (equivalently α′^{N−1} ~ w^{2−2N}), imported from [22]. With α′ held fixed, the α′^{N−1} Riem^N corrections would diverge at order w^{2N−2} after the measure. The paper should state explicitly, in the abstract and §VI, that finiteness holds relative to this scaled α′, and give a physical justification or reference establishing that this is the appropriate Carrollian scaling of the string expansion (e.g., which tensionless/null-string limit realizes it). Without this, 'admits a finite Carrollian limit' is stronger than what is shown.
minor comments (6)
  1. [Eq. (13)] Index mismatch: Ĥ_{μνρ} = h_{μνρ} + f_{νρσ} should presumably be f_{μνρ} (defined in (15)).
  2. [Eq. (37)] The left-hand side is missing the hat: it should read \hat R^ρ_{ σμν} = R^ρ_{ σμν} + O(w^{−2}).
  3. [Eq. (26)] The two lines differ only by the swap α ↔ λ on the last two factors; please state that this is the antisymmetrization descending from the index structure of the ĤĤR̂ contraction in (3), so the reader can parse the identity.
  4. [§V, Eqs. (28)–(30)] The conditions ∇_μh_{νρ} = 0 and ∇_μτ_ν = 0 are strong (covariantly constant Carrollian structure). Please comment on whether non-trivial solutions exist in 26 dimensions and on which class of Carrollian geometries the explicit action (31) applies. The sentence after (30) ('∇_{[μ}τ_{ν]} is arbitrary and completely fixes ∇_{(μ}τ_{ν)}') also needs a clause of explanation.
  5. [§VI, Eq. (44)] Please verify the index balance of (44): the first line contracts four Riemanns with 8 τ's and 4 h's, the second with 8 τ's and 2 h's; confirming both descend from the same parent invariant (43) would help the reader trust the unshown cancellations.
  6. [General] Typos/grammar: 'we we will extend' (end of §V); 'ona can easily count' (§VI); 'no divergence arise' (§VI); 'This result do not apply' and 'stablish' (§VI); 'simplifies considerable' (§V); duplicated 'theLM T' (§III). Also, since the leading-order finiteness and the Riem² analysis are imported from the companion preprint [22], a brief self-contained summary of the relevant w-counting from that work would make this paper readable standalone.

Circularity Check

0 steps flagged

No significant circularity: the paper expands an external Metsaev–Tseytlin/higher-α' Lagrangian under a fixed Carrollian ansatz; finiteness is not true by definition of the inputs.

full rationale

The derivation chain is: (i) take the standard bosonic effective Lagrangians (Metsaev–Tseytlin and the pure-gravitational α'²/α'³ densities from the literature); (ii) substitute the Carrollian field ansatz and the α'∼1/w² rescaling already fixed in the author’s prior leading-order paper [22]; (iii) expand in w and claim cancellation or power-counting finiteness. Step (ii) is ordinary sequential dependence on prior setup, not a self-definitional loop: the target claims (exact cancellation of the w⁶ H–Riem sector independent of non-metricity; O(w⁰) balance for Riem^N; vanishing of the ζ(3) sector) are not built into the definition of the ansatz or the rescaling. There are no fitted parameters re-presented as predictions, no uniqueness theorem imported to forbid alternatives, and no renaming of a known empirical pattern. Whether the asserted algebraic cancellations are actually displayed is a verification/correctness issue, not circularity. Score 1 only for the mild, non-load-bearing reliance on [22] for the ansatz and leading-order scaling that every higher-order count uses.

Axiom & Free-Parameter Ledger

0 free parameters · 5 axioms · 0 invented entities

The paper is a classical effective-field-theory calculation. It inherits the Metsaev–Tseytlin and higher-α' Lagrangians, the Carrollian decomposition and the α' rescaling from prior work, then performs tensor expansions. No empirical fits; the only structural choices are the geometric ansatz, the α' scaling, and optional compatibility conditions used for the covariant form and the universal criterion.

axioms (5)
  • domain assumption Metsaev–Tseytlin four-derivative bosonic effective Lagrangian (and the pure-gravitational α'²/α'³ Lagrangians of Ameri–Pahlavan–Garousi) correctly capture the low-energy string S-matrix.
    Taken as given in §III and §VI; all finiteness statements are statements about these specific actions.
  • domain assumption Carrollian ansatz ĝμν=hμν−w⁻²τμτν (and analogous B, ϕ) with constitutive relations τ·h=0, τ·τ=1, together with the dilaton shift that produces the Carrollian measure factor w⁻².
    Imported from [22] and stated in §III; every power of w is counted relative to this decomposition.
  • ad hoc to paper α' is rescaled as α'=α'_C/w² (and α'^{N-1}∼w^{2-2N}) so that the leading higher-derivative sector can balance the measure.
    Stated in §III as the same rescaling used at leading order; without it the action would not be O(w⁰).
  • domain assumption Compatibility conditions ∇μhνρ=0 and ∇μτν=0 (with the residual non-metricity relations that follow) may be imposed to obtain a finite Riemann tensor and the universal criterion.
    Imposed in §V–VI for the explicit action and the Riem^N argument; the paper notes that the four-derivative cancellation itself does not require them.
  • standard math Standard torsion-free Levi-Civita-type connection built from τ and h, and the usual algebraic definition of the Riemann tensor from [∇,∇].
    Eqs. (16)–(21); ordinary differential geometry.

pith-pipeline@v1.2.0-grok45-kimik3 · 16966 in / 3223 out tokens · 70679 ms · 2026-07-31T05:58:42.420429+00:00 · methodology

0 comments
read the original abstract

We prove that the Carrollian limit of bosonic supergravity remains finite after including the four-derivative terms arising from the $\alpha'$-corrections, and we explicitly construct the effective action. We also establish a universal criterion to determine the finiteness of higher-curvature contributions given by powers of the Riemann tensor, ${\rm Riem}_1 \cdots {\rm Riem}_N$, with $N>1$. As applications of this criterion, we prove that the purely gravitational $\alpha'^2$- and $\alpha'^3$-corrections admit a finite Carrollian limit, derive their explicit contributions to the action, and show that the terms proportional to $\zeta(3)$ do not contribute to the Carrollian bosonic supergravity at order $\alpha'^3$.

discussion (0)

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

Reference graph

Works this paper leans on

52 extracted references · 29 linked inside Pith

  1. [1]

    On an Analogue of the Galileo Group,

    N. Sen Gupta, “On an Analogue of the Galileo Group,” Nuovo Cim. 54 (1966) 512, DOI: 10.1007/BF02740871

  2. [2]

    Now we extract all the divergent terms coming from the MT action. Particularly they arew 6 contributions coming from the ˆRiem ˆH ˆHcontribution, L(6) M T =− 1 2 ˆHµνρ ˆHσγϵ ˆR(2)µ δλατ ντ στ δτ αhργhϵλ + 1 2 ˆHµνρ ˆHσγϵ ˆR(2)µ δλατ ντ στ δτ λhργhϵα,(26) where ˆ2R(2)ρ ϵµν =−∇ µτ ρ∇ϵhνσ τ σ − ∇µτ ρ∇νhϵστ σ +∇ µτ ρ∇σhϵντ σ − ∇µτ σ∇ϵhνσ τ ρ − ∇µτ σ∇νhϵστ ρ +...

  3. [3]

    Carrollian Physics at the Black Hole Horizon,

    L. Donnay and C. Marteau, “Carrollian Physics at the Black Hole Horizon,” Class. Quant. Grav. 36 no. 16, (2019) 165002

  4. [4]

    Une nouvelle limite non-relativiste du group de Poincare,

    J. Levy-Leblond, “Une nouvelle limite non-relativiste du group de Poincare,” Ann.Inst.Henri Poincare 3 (1965) 1

  5. [5]

    Asymptotic symmetries in Carrollian theories of gravity,

    A. P´ erez, “Asymptotic symmetries in Carrollian theories of gravity,” JHEP 12 (2021) 173, arXiv:2110.15834 [hep-th]

  6. [6]

    Carroll Expansion of General Relativity,

    D. Hansen, N. A. Obers, G. Oling, and B. T. Søgaard, “Carroll Expansion of General Relativity,” SciPost Phys. 13 no. 3, (2022) 055, arXiv:2112.12684 [hep-th]

  7. [7]

    Carroll black holes,

    F. Ecker, D. Grumiller, J. Hartong, A. P´ erez, S. Prohazka, and R. Troncoso, “Carroll black holes,” arXiv:2308.10947 [hep-th]

  8. [8]

    Non-linear black hole dynamics and Carrollian fluids,

    J. Redondo-Yuste and L. Lehner, “Non-linear black hole dynamics and Carrollian fluids,” JHEP 02 (2023) 240, arXiv:2212.06175 [gr-qc]

  9. [9]

    Bagchi, A

    A. Bagchi, A. Banerjee, J. Hartong, E. Have, K. S. Kolekar, ”Strings near black holes are Carrollian. Part II”, JHEP 11 (2024) 024

  10. [10]

    Bagchi, A

    A. Bagchi, A. Banerjee, J. Hartong, E. Have, K. S. Kolekar, ”Strings near black holes are Carrollian”, Phys.Rev.D 110 (2024) 8, 086009

  11. [11]

    Holography of 3D Flat Cosmological Horizons,

    A. Bagchi, S. Detournay, R. Fareghbal, and J. Simon, “Holography of 3D Flat Cosmological Horizons,” Phys.Rev.Lett. 110 no. 14, (2013) 141302

  12. [12]

    Correspondence between Asymptotically Flat Spacetimes and Nonrelativistic Conformal Field Theories,

    A. Bagchi, “Correspondence between Asymptotically Flat Spacetimes and Nonrelativistic Conformal Field Theories,” Phys.Rev.Lett. 105 (2010) 171601

  13. [13]

    Carrollian approach to 1 + 3D flat holography,

    A. Saha, “Carrollian approach to 1 + 3D flat holography,” JHEP 06 (2023) 051, arXiv:2304.02696 [hep-th]

  14. [14]

    Holographic Reconstruction of 3D Flat Space-Time,

    J. Hartong, “Holographic Reconstruction of 3D Flat Space-Time,” JHEP 10 (2016) 104

  15. [15]

    A Carroll Limit of AdS/CFT: A Triality with Flat Space Holography?,

    A. Fontanella and O. Payne, “A Carroll Limit of AdS/CFT: A Triality with Flat Space Holography?,” arXiv:2508.10085 [hep-th]

  16. [16]

    Holography in Flat Spacetimes: the case for Carroll,

    A. Bagchi, P. Dhivakar, and S. Dutta, “Holography in Flat Spacetimes: the case for Carroll,” arXiv:2311.11246 [hep-th]

  17. [17]

    Scattering Amplitudes: Celestial and Carrollian,

    A. Bagchi, S. Banerjee, R. Basu, and S. Dutta, “Scattering Amplitudes: Celestial and Carrollian,” Phys. Rev. Lett. 128 no. 24, (2022) 241601. 6

  18. [18]

    Carrollian Perspective on Celestial Holography,

    L. Donnay, A. Fiorucci, Y. Herfray, and R. Ruzziconi, “Carrollian Perspective on Celestial Holography,” Phys. Rev. Lett. 129 no. 7, (2022) 071602

  19. [19]

    Argando˜ na, A

    A. Argando˜ na, A. Guijosa, S. Pati˜ no-L´ opez, ”De Sitter Holography and Carrollian brane theories”, JHEP 10 (2025) 133, e-Print: 2507.06147 [hep-th]

  20. [20]

    Bridging Carrollian and celestial holography,

    L. Donnay, A. Fiorucci, Y. Herfray, and R. Ruzziconi, “Bridging Carrollian and celestial holography,” Phys. Rev. D 107 no. 12, (2023) 126027, arXiv:2212.12553 [hep-th]

  21. [21]

    So far, it has remained unknown whether the inclusion of stringyα ′-corrections preserves the consistency of the Carrollian limit

    for a pedagogical review). So far, it has remained unknown whether the inclusion of stringyα ′-corrections preserves the consistency of the Carrollian limit. Indeed, the higher-derivative action de- velops apparent divergences at intermediate stages of the expansion, making it unclear whether a finite Carrollian theory exists beyond leading order. II. MAI...

  22. [22]

    Order alpha-prime (Two Loop) Equivalence of the String Equations of Motion and the Sigma Model Weyl Invariance Conditions: Dependence on the Dilaton and the Antisymmetric Tensor,

    R. R. Metsaev and A. A. Tseytlin, “Order alpha-prime (Two Loop) Equivalence of the String Equations of Motion and the Sigma Model Weyl Invariance Conditions: Dependence on the Dilaton and the Antisymmetric Tensor,” Nucl. Phys. B 293 (1987) 385

  23. [23]

    α ′-corrections and their double formulation

    E. Lescano, “α ′-corrections and their double formulation”, J.Phys.A 55 (2022) 5, 053002, 2108.12246 [hep-th]

  24. [24]

    Carrollian limit of NS-NS and Heterotic Supergravity

    R. Ballesteros, E. Lescano, S. Pati˜ no-L´ opez, “Carrollian limit of NS-NS and Heterotic Supergravity”, 2607.09847 [hep-th]

  25. [25]

    The Quartic Effective Action for the Heterotic String,

    D. J. Gross and J. H. Sloan, “The Quartic Effective Action for the Heterotic String,” Nucl. Phys. B 291 (1987), 41-89 doi:10.1016/0550-3213(87)90465-2

  26. [26]

    Heterotic String Covariant Amplitudes and Low-energy Effective Action,

    Y. Cai and C. A. Nunez, “Heterotic String Covariant Amplitudes and Low-energy Effective Action,” Nucl. Phys. B 287, 279 (1987)

  27. [27]

    Effective action of bosonic string theory at orderα ′3

    M. Ameri, A. Pahlavan, M. R. Garousi, “Effective action of bosonic string theory at orderα ′3”, JHEP 12 (2025) 132

  28. [28]

    No manifest T duality at orderα ′3

    S. Weilong Hsia, A. Rakin Kamal, L. Wulff, “No manifest T duality at orderα ′3”, Phys.Rev.D 111 (2025) 6, L061904, 2411.15302 [hep-th]

  29. [29]

    IIA/B, wound and wrapped,

    U. H. Danielsson, A. Guijosa, and M. Kruczenski, “IIA/B, wound and wrapped,” JHEP 10 (2000) 020, arXiv:hep- th/0009182

  30. [30]

    Nonrelativistic closed string theory,

    J. Gomis and H. Ooguri, “Nonrelativistic closed string theory,” J. Math. Phys., vol. 42, pp. 3127–3151, 2001

  31. [31]

    Newtonian gravitons and D-brane collective coordinates in wound string theory,

    U. H. Danielsson, A. Guijosa, and M. Kruczenski, “Newtonian gravitons and D-brane collective coordinates in wound string theory,” JHEP 03 (2001) 041, arXiv:hep-th/0012183

  32. [32]

    Aspects of Nonrelativistic Strings,

    G. Oling and Z. Yan, “Aspects of Nonrelativistic Strings,” Front. in Phys. 10 (2022) 832271, arXiv:hep-th/2202.12698

  33. [33]

    Review on Non-Relativistic Gravity

    J. Hartong, N. A. Obers, and G. Oling, “Review on Non-Relativistic Gravity”, arXiv:hep-th/2212.11309

  34. [34]

    Curvatures and Non-metricities in the Non-Relativistic Limit of Bosonic Supergravity

    E. Lescano, “Curvatures and Non-metricities in the Non-Relativistic Limit of Bosonic Supergravity”, e-Print: 2601.03342 [hep-th]

  35. [35]

    Lescano, J

    E. Lescano, J. Rosseel and S. Zeko, Work in progress

  36. [36]

    A unified expansion of Einstein’s gravity

    A. Bhattacharya, P. Soni, “A unified expansion of Einstein’s gravity”, 2607.16459 [hep-th]

  37. [37]

    Gravitational four-derivative corrections in non-relativistic heterotic supergravity and the SO(8) Green- Schwarz mechanism

    E. Lescano, “Gravitational four-derivative corrections in non-relativistic heterotic supergravity and the SO(8) Green- Schwarz mechanism”, e-Print: 2508.09250 [hep-th]

  38. [38]

    E. A. Bergshoeff and L. Romano, Non-relativistic heterotic string theory, JHEP 01 (2024) 146, arXiv:hep-th/2310.19716

  39. [39]

    Lescano and D

    E. Lescano and D. Osten, Non-relativistic limits of bosonic and heterotic Double Field Theory, JHEP 07 (2024) 286

  40. [40]

    A Non-Relativistic Limit for Heterotic Supergravity and its Gauge Lagrangian

    E. Lescano, “A Non-Relativistic Limit for Heterotic Supergravity and its Gauge Lagrangian”, Nucl.Phys.B 1028 2026, 117487, 2502.08711 [hep-th]

  41. [41]

    Trivialization of the gravitational Green-Schwarz transformation in the nonrelativistic limit of string theory

    E. Lescano, “Trivialization of the gravitational Green-Schwarz transformation in the nonrelativistic limit of string theory”, Phys.Rev.D 113 (2026) 4, L041902

  42. [42]

    Classification of non-Riemannian doubled-yet-gauged spacetime

    K. Morand and J.-H. Park, “Classification of non-Riemannian doubled-yet-gauged spacetime”, Eur. Phys. J. C 77 (2017), no. 10 685, [arXiv:1707.03713]. [Erratum: Eur.Phys.J.C 78, 901 (2018)]

  43. [43]

    Non-Riemannian gravity actions from double field theory

    A. D. Gallegos, U. Gursoy, S. Verma, and N. Zinnato, “Non-Riemannian gravity actions from double field theory”, JHEP 06 (2021) 173, [arXiv:2012.07765]

  44. [44]

    Double field theory at orderα ′,

    O. Hohm and B. Zwiebach, “Double field theory at orderα ′,” JHEP 11 (2014), 075, 1407.3803 [hep-th]

  45. [45]

    T-duality andα’-corrections,

    D. Marques and C. A. Nunez, “T-duality andα’-corrections,” JHEP 10 (2015), 084, 1507.00652 [hep-th]

  46. [46]

    On the Consistency of Null Strings Literature: The Tale of an Overlooked Sym- metry

    M.M. Sheikh-Jabbari, H. Yavartanoo, “On the Consistency of Null Strings Literature: The Tale of an Overlooked Sym- metry”, 2605.12414 [hep-th]

  47. [47]

    Null Strings Gauged and Reloaded, I: Null Strings Have Carroll-Weyl Gauge Symmetry

    M.M. Sheikh-Jabbari, H. Yavartanoo, “Null Strings Gauged and Reloaded, I: Null Strings Have Carroll-Weyl Gauge Symmetry”, 2605.25817 [hep-th]

  48. [48]

    Null Strings Gauged and Reloaded, II: Consistent Classical Treatment of the Null Strings

    M.M. Sheikh-Jabbari, H. Yavartanoo, “Null Strings Gauged and Reloaded, II: Consistent Classical Treatment of the Null Strings”, 2605.26822 [hep-th]

  49. [49]

    Symmetries of tensionless strings

    U. Lindstrom, “Symmetries of tensionless strings”, 2605.26185 [hep-th]

  50. [50]

    Path integral quantization of null bosonic strings with Carroll-Weyl ghosts

    S. Duary, S. Maji, “Path integral quantization of null bosonic strings with Carroll-Weyl ghosts”, 2606.04999 [hep-th]

  51. [51]

    The conformal null string in d+2 and d dimensions

    U. Lindstrom, “The conformal null string in d+2 and d dimensions”, 2606.22498 [hep-th]

  52. [52]

    Null-strings Gauged, Reloaded and Quantized, I: Canonical Quantization in the Light-Cone Gauge

    Ida M. Rasulian, M.M. Sheikh-Jabbari, H. Yavartanoo, “Null-strings Gauged, Reloaded and Quantized, I: Canonical Quantization in the Light-Cone Gauge”, 2607.02970 [hep-th]. 7 Appendix A: Explicit form of thefµνρ contributions to the four-derivative action Here we provide the explicit form of the f-contributions in (33), − 1 2 [ ˆH µνρ ˆHµσλ ˆRνρ σλ](4)|f =...