Pith. sign in

REVIEW 5 major objections 4 minor 95 references

Non-relativistic Strings: Classical solutions and exactly solvable models

T0 review · 5 major / 4 minor · reviewed 2026-08-16 · deepseek-v4-flash

Pith's one-line read Non-relativistic strings on a two-sphere reduce to exactly solvable models at leading and next-to-leading order in a 1/c^2 expansion, with Bohr-Sommerfeld energies growing quadratically and then linearly with quantum number.

desk verdict The large-c framework and NLO fluctuations are worth a look, but the Bohr-Sommerfeld spectra and the intrinsic GKP/spinning calculations have elementary algebraic holes that sink the central claims. read the letter →

arxiv 2504.20252 v2 pith:AYW7TGNE submitted 2025-04-28 hep-th

classification hep-th
keywords non-relativisticstringNewton-CartanexactlysolvablemodelsNeumann-RosochatiusBohr-SommerfeldquantizationGKPGiantMagnon1/c^2expansion
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 works out classical string solutions when the target space is a non-relativistic (string Newton-Cartan) version of R x $S^{2}$, and shows that the dynamics reduces to exactly solvable Neumann-Rosochatius-like models. On the intrinsic non-relativistic string side, it finds GKP-type and spinning string configurations with dispersion relations that resemble relativistic counterparts, including a small-momentum limit of the Giant Magnon relation. On the large-speed-of-light expansion side, it derives the dynamics of spinning and pulsating strings at leading and next-to-leading order, constructs equivalent solvable Hamiltonians, and quantizes the energies using the Bohr-Sommerfeld condition. The resulting energy spectra scale as $n^{2}$ at leading order and as n at next-to-leading order, in contrast to relativistic string spectra. A sympathetic reader would care because exact solvability in non-relativistic string theory is rare, and these models provide a concrete testing ground for non-relativistic holography and integrability.

What carries the argument

The central machinery is the 1/$c^{2}$ expansion of the relativistic Polyakov action, with worldsheet gauge fixing h^(1)_ab = 0, together with sphere-constraint relations that tie the leading-order and next-to-leading-order embedding coordinates. This produces Neumann-Rosochatius-like Hamiltonians with harmonic and inverse-square potentials. The Bohr-Sommerfeld quantization condition is used to extract energy spectra.

What would settle it

Re-derive the next-to-leading-order dynamics of a spinning string on R x $S^{2}$ from the un-gauge-fixed 1/$c^{2}$-expanded Polyakov action, keeping h^(1)_ab degrees of freedom, and check whether the resulting equations of motion reproduce the Neumann-Rosochatius-like Hamiltonian (4.24) or contain additional worldsheet modes. If additional modes alter the dynamics, the claimed NLO solvable model and its linear-in-n spectrum are artifacts of the gauge fixing.

Watch

Extended reading notes

Core claim

For closed strings moving in a non-relativistic R x $S^{2}$ target space, both the intrinsic string Newton-Cartan $\sigma$ model and the large-c expansion of the relativistic Polyakov action yield classical solutions whose dynamics is governed by integrable, Neumann-Rosochatius-type systems. In the intrinsic formalism, a GKP-like folded string still obeys a dispersion relation of the form E - J = constant, and a rigid spinning string produces a relation that can be interpreted as the small-momentum limit of the Giant Magnon dispersion. In the 1/$c^{2}$-expanded formalism, the leading-order Lagrangians for spinning and pulsating strings are exactly solvable harmonic-oscillator-type systems on a sphere, while the next-to-leading-order dynamics, after imposing constraints that couple the leading and subleading embedding fields, is captured by deformed Neumann-Rosochatius-like Hamiltonians. Bohr-Sommerfeld quantization of these Hamiltonians gives energy levels growing like $n^{2}$ at leading order and linearly in n at next-to-leading order.

Load-bearing premise

The next-to-leading-order dynamics of the expanded Polyakov action is fully captured by the truncated action with the worldsheet gauge choice h^(1)_ab = 0, and this truncated action is equivalent to the intrinsic string Newton-Cartan $\sigma$ model.

Editorial extensions

If this is right

  • The Bohr-Sommerfeld spectra give concrete predictions for discrete energy levels of non-relativistic spinning and pulsating strings in this background, which could be compared with a dual field theory if a holographic dual is identified.
  • The exact solvability of the LO and NLO systems suggests that integrable-structure methods (Lax pairs, conserved charges, separation of variables) can be applied to non-relativistic string sigma models on curved backgrounds.
  • The new dispersion relations provide concrete targets for testing non-relativistic holography: dual operators would be expected to have anomalous dimensions growing polynomially with spin or oscillation number, rather than logarithmically as in the relativistic case.
  • The NLO Neumann-Rosochatius-like systems, with their deformed kinetic terms and constrained phase spaces, could serve as toy models for understanding integrability in non-relativistic string theory beyond simple flat-space examples.

Reading between the lines

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

  • The paper's method suggests a systematic recipe for other compact target spaces: expand the Polyakov action in 1/c^2, impose the sphere-type constraints order by order, and search for Neumann-Rosochatius-like Hamiltonians. AdS-type spaces with more transverse directions might yield multi-dimensional generalizations of these solvable systems.
  • If the truncated NLO dynamics is the true string dynamics (i.e., if the h^(1)_ab = 0 gauge fixing is valid), then the linear-in-n NLO spectrum might be a distinctive signature of non-relativistic strings that could be searched for in lattice or spin-chain models of non-relativistic holography.
  • The claim that the spinning string dispersion approaches the small-momentum Giant Magnon relation could be sharpened by constructing the explicit soliton (kink) profile and computing its worldsheet momentum; this would test whether the interpretation as a genuine Giant Magnon holds or whether it is only a limiting scaling relation.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

5 major / 4 minor

Summary. The manuscript studies closed-string solutions in a non-relativistic version of the R×S2 target space using two complementary frameworks: the intrinsic string Newton-Cartan (sNC) sigma model, and the 1/c^2 expansion of the relativistic Polyakov action. In the intrinsic model it constructs GKP-type and rigid spinning string solutions and derives dispersion relations (2.18) and (2.33)-(2.34). In the expanded theory it reduces the leading-order (LO) and next-to-leading-order (NLO) spinning and pulsating string dynamics to Neumann-Rosochatius-like Hamiltonians, Eqs. (4.24), (4.26) and (5.20), and applies Bohr-Sommerfeld quantization to obtain energy spectra scaling as E~n_LO^2 at LO and E~n_NLO at NLO.

Significance. The topic is timely, and the paper contains useful explicit material: the sNC constraint analysis in §2, the large-c expansion of the Polyakov action in §3, and the construction of constrained radial models in §§4-5. If the advertised results were correct, they would provide a solvable sector of non-relativistic string theory with concrete semiclassical spectra, and the comparison with relativistic GKP and Giant Magnon dispersions would be of interest. However, several of the central quantitative outputs do not follow from the paper's own equations: the GKP energy vanishes for integer winding, the spinning-string charges contain divergent integrals, and the Bohr-Sommerfeld spectra in §4.3 and §5.1 are algebraically inconsistent with the stated Hamiltonians and quantization conditions. These are load-bearing errors in the paper's main claims, so the manuscript cannot be accepted in its present form.

major comments (5)
  1. [§2.2, Eqs. (2.16)-(2.18)] For the GKP solution with integer winding κ, the integral ∫_0^{2π} cos(2κσ+2σ0)dσ vanishes identically, so the energy E in Eq. (2.16) is zero. The scaled dispersion relation (2.18) then reduces to a trivial statement involving only the angular momentum, and the claimed GKP-type dispersion relation is empty. The comparison with the relativistic GKP string in the following paragraph is therefore not supported by the computation.
  2. [§2.3, Eqs. (2.23), (2.25), (2.31)-(2.32)] The constraint solution r1=sin(κσ+σ0) reaches the poles ϑ=0,π of the sphere. Consequently the integrals ∫ dϑ/sin^2ϑ appearing in the energy (2.31a) and in the deficit angle Δφ (2.32) diverge at the endpoints, and the function f(σ) obtained from f'=v/sin^2(κσ+σ0) is not single-valued or periodic on the closed string. The dispersion relation (2.33)-(2.34) and the small-momentum Giant Magnon interpretation are therefore invalid without additional restrictions that are neither stated nor satisfied by this solution.
  3. [§4.3, Eqs. (4.27)-(4.32)] The Bohr-Sommerfeld condition (4.30) applied to the Hamiltonian (4.27) gives π_{r1^(0)}^2(1-(r1^(0))^2)=eTeff(eTeffκ0^2−2E). For the bounded orbit r1^(0)∈[-1,1], the closed-orbit action is ∮π_{r1^(0)}dr1^(0)=2π√(eTeff(eTeffκ0^2−2E)). Equating this to n_LO yields E=eTeffκ0^2/2−n_LO^2/(8π^2eTeff), not Eq. (4.32). The quoted spectrum E=2n_LO^2/(π^2eTeff)+eTeffκ0^2/2 cannot be derived from the stated Hamiltonian; both the sign and the coefficient of the n_LO^2 term are wrong. Since this spectrum is one of the main advertised results, the central claim of the 1/c^2 analysis fails.
  4. [§5.1, Eqs. (5.8)-(5.12)] There are two independent problems in the pulsating-string quantization. First, the oscillation number is defined in (5.10) as N_LO=Teff∮π_{r1^(0)}dr1^(0), but the integral actually evaluated in (5.11) is Teff∫_0^1, which is one quarter of the standard closed-orbit action for this symmetric phase-space curve; with the stated ∮ the coefficient in (5.12) becomes 1/(8π^2eTeff^3), not 2/(π^2eTeff^3), a factor of 16. Second, H_LO in (5.9) is the worldsheet canonical Hamiltonian, whereas the target-space energy is defined in (5.8) as E=eTeffζ; equating H_LO with E_LO conflates two different conserved quantities. The pulsating-string energy spectrum is therefore not established.
  5. [Appendix B and §4.2] The claim that the NLO systems are exactly solvable or Liouville integrable is not demonstrated. The Hamiltonians (4.24) and (5.20) are constructed so that their Hamilton equations reproduce the previously derived equations of motion (4.18), and the proposed integral of motion in (B.4) is checked only after substituting explicit LO on-shell solutions and imposing the condition (B.8). No proof of Poisson involution on the constrained phase space or of Liouville integrability is given, so the terminology 'exactly solvable' is stronger than what the manuscript establishes.
minor comments (4)
  1. [Eq. (2.15)] The coefficient of cos(2κσ+2σ0) in Eq. (2.15) appears to be off by a factor of κ; integrating the equation of motion for ξ1 gives (κω^2/2)cos(2κσ+2σ0) rather than the expression as written, unless a different convention is intended.
  2. [Eqs. (4.19)-(4.21)] The derivative of the quoted solution for θ^(1) has denominator a^2, while the right-hand side of Eq. (4.19) has denominator a; this indicates a consistency error that should be checked between Eq. (4.18) and Eqs. (4.20)-(4.21).
  3. [Figures 1 and 4] The plotted functions contain cot and csc^2 terms and diverge at σ=0,π (or τ=0,π) for the parameter values shown, yet the captions describe them as periodic. These are not smooth periodic functions on the closed string, so the figures should be revisited or the parameter ranges restricted.
  4. [Notation throughout] The symbol 'eTeff' is used extensively without being defined explicitly at first use; if it denotes the product e·Teff, this should be stated, and if not, the notation should be clarified.

Circularity Check

1 steps flagged · score 3.0 of 10

No fitted-input or self-citation circularity in the central derivations; one mild self-consistency loop in the Appendix-B NLO integrability construction.

  1. self definitional [Appendix B, Eqs. (B.4)-(B.8)]
    "To consider the above expression as the integral of motion of the equivalent NR-like model at NLO, we must need the condition I′ = 0. After substituting the solutions for the r-coordinates of both the LO and NLO dynamics in (B.4) and using the condition (B.5), we get with LO on shell , f(σ) = ..."

    The deformed Uhlenbeck-type invariant is not obtained from an independent symmetry, Lax pair, or prior integrability theorem. Instead, the undetermined function f(σ) is solved from the requirement I'=0 and then I is declared an integral of motion. The conservation law is thus enforced by construction, so it cannot independently demonstrate Liouville integrability. Moreover, the subsequent Poisson-bracket check {I,H_NR}=0 holds only under the extra on-shell condition (B.8), making the NLO integrability claim a self-consistency statement rather than evidence derived from the dynamics.

full rationale

The paper's main derivations are largely self-contained. The intrinsic sNC-model dispersion relations in Sections 2.2 and 2.3 are Noether charges computed from the action, not fitted inputs; the GKP and spinning-string relations follow from the explicit equations of motion. The 1/c^2 expansion is taken from the cited formalism of [33,34], and the admitted h^(1)_ab=0 caveat in footnote 14 is a validity/justification concern, not a circular one. The LO Bohr-Sommerfeld spectra are obtained by solving the paper's own phase-space integrals rather than by fitting data or importing an external result. The reviewer-noted algebraic mismatch between (4.30)-(4.32) and (5.10)-(5.12) is best classified as an internal-consistency or correctness issue: if the quantization integrals do not yield the announced n^2 and n scalings, the calculation is erroneous or mis-derived, but it is not an input restated as an output. The one genuinely circular-adjacent element is the NLO integrability discussion in Appendix B, where the conserved quantity is built by imposing I'=0 and then used as evidence of solvability; this is a mild self-consistency loop rather than a prediction reduced to a fit. No load-bearing self-citations were found; the author-self references appear in peripheral contexts and do not carry the central argument. Overall score 3.

Assumptions & free parameters 7 free parameters · 5 assumptions · 0 invented entities

No empirical data are used, so the free parameters are ansatz and integration constants rather than fitted values. The central claim depends on the background sNC and large-c formalisms, on the partial gauge fixing used to identify the NLO action, on the validity of Bohr-Sommerfeld quantization, and on a regularity assumption about pole-crossing embeddings. No new particle, force, dimension, or conserved charge is introduced.

free parameters (7)
  • kappa0 (static-gauge time frequency, spinning) = integer constant
    Sets t^(0) = kappa0 tau; enters the LO Lagrangian (4.3) and all quantized energies in (4.27)-(4.32).
  • omega (azimuthal angular velocity) = constant
    Appears in the spinning-string potential A^2/r^2 - omega^2 r^2 and in the spectra and NLO solutions (4.20).
  • A or v (spinning-string integration constant) = constant
    Defines f'(sigma) = v/r1^2 and f(sigma) = A cot(a sigma + b)/a in (4.16); controls the dispersion (2.33) and NLO radial corrections.
  • a or kappa (winding number in r1 = sin(a sigma + b)) = integer
    Determines periodicity in sigma and enters the NLO integrals, the Bohr-Sommerfeld limits, and the extra integrability condition (B.8).
  • m (pulsating azimuthal winding) = integer
    Sets the pulsating potential B^2/r^2 - m^2 r^2 and the NLO pulsating spectra in (5.20)-(5.23).
  • B (pulsating integration constant) = constant
    Comes from fdot^(0) = B/r1^2 in (5.14) and governs the NLO pulsating solution (5.16)-(5.18).
  • alpha and tau0 (pulsating oscillation amplitude and phase) = constants
    Set the LO pulsating solution r1 = sin(alpha tau + tau0); they appear in NLO solutions and in the validity conditions for the spectra in (5.22).
assumptions (5)
  • domain assumption The string Newton-Cartan action (2.1) with constraints (2.4)-(2.5) describes non-relativistic string dynamics on R x S2.
    Taken from prior literature [25,75]; all intrinsic sNC results inherit this formalism without independent derivation.
  • domain assumption The large-c expansion of the Polyakov action truncated at NLO with h^(0) = eta and h^(1) = 0 is equivalent to the intrinsic sNC sigma model.
    Introduced in section 3 after Eq. (3.11); footnote 14 concedes the identification may be too quick in general cases.
  • standard math Bohr-Sommerfeld quantization, in the form contour-integral pi_r dr = n, applies to these constrained non-relativistic systems and can be expanded order by order as in (4.30)-(4.31).
    Section 4.3 invokes semiclassical quantization without a derivation for the constrained phase space; the resulting spectra are not consistent with the quoted integrals.
  • ad hoc to paper The singular worldsheet fields such as f'(sigma) = v/sin^2(kappa sigma) satisfy closed-string periodicity and give finite charges.
    In (2.23)-(2.32), r1 = sin(kappa sigma) places poles in f', E, J, and Delta phi at the sphere poles; no regularization or boundary treatment is specified.
  • ad hoc to paper The NLO radial dynamics is faithfully represented by the Neumann-Rosochatius-like Hamiltonians (4.24) and (5.20) despite their nonstandard kinetic and coupling structure.
    The Hamiltonians are written to reproduce the NLO equations of motion, and Appendix B shows Poisson integrability only under an extra condition (B.8).

how reviews work

0 comments
Cite this review

Pith. "Pith review of Non-relativistic Strings: Classical solutions and exactly solvable models." pith.science (2026). https://pith.science/paper/AYW7TGNE

@misc{pith2026250420252,
  author       = {Pith},
  title        = {Pith review of: Non-relativistic Strings: Classical solutions and exactly solvable models},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/AYW7TGNE}},
  note         = {Machine review of arXiv:2504.20252}
}
read the original abstract

We discuss classical closed string solutions in non-relativistic two-sphere target spaces. These classes of solutions closely relate to the GKP-type, spinning and pulsating strings for the relativistic case. We derive the string dynamics in each case and construct relevant dispersion relations, both from the string Newton-Cartan intrinsic sigma model and using a large speed of light expansion of relativistic Polyakov action. We further discuss construction and characteristics of exactly solvable Neumann-Rosochatius-like dynamical systems corresponding to strings in leading and subleading orders of the expanded Polyakov theory.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

95 extracted references · 31 canonical work pages

  1. [1]

    Bergshoeff, J

    E. Bergshoeff, J. Figueroa-O’Farrill and J. Gomis,A non-lorentzian primer, SciPost Phys. Lect. Notes 69 (2023) 1 [2206.12177]

  2. [2]

    Cartan,On manifolds with an affine connection and the theory of relativity,(english translation by a

    E. Cartan,On manifolds with an affine connection and the theory of relativity,(english translation by a. ashtekar of a series of french articles from 1923 to 1926) bibliopolis, 1986

  3. [3]

    HAVAS,Four-Dimensional Formulations of Newtonian Mechanics and Their Relation to the Special and the General Theory of Relativity, Rev

    P. HAVAS,Four-Dimensional Formulations of Newtonian Mechanics and Their Relation to the Special and the General Theory of Relativity, Rev. Mod. Phys.36 (1964) 938

  4. [4]

    Hartong, N.A

    J. Hartong, N.A. Obers and G. Oling,Review on Non-Relativistic Gravity, Front. in Phys. 11 (2023) 1116888 [2212.11309]

  5. [5]

    Son,Newton-Cartan Geometry and the Quantum Hall Effect, 1306.0638

    D.T. Son,Newton-Cartan Geometry and the Quantum Hall Effect, 1306.0638

  6. [6]

    Hartong, E

    J. Hartong, E. Kiritsis and N.A. Obers,Field Theory on Newton-Cartan Backgrounds and Symmetries of the Lifshitz Vacuum, JHEP 08 (2015) 006 [1502.00228]

  7. [7]

    Van den Bleeken and C

    D. Van den Bleeken and C. Yunus,Newton-Cartan, Galileo-Maxwell and Kaluza-Klein, Class. Quant. Grav.33 (2016) 137002 [1512.03799]

  8. [8]

    Festuccia, D

    G. Festuccia, D. Hansen, J. Hartong and N.A. Obers,Symmetries and Couplings of Non-Relativistic Electrodynamics, JHEP 11 (2016) 037 [1607.01753]

Show all 95 references
  1. [9]

    Bagchi, R

    A. Bagchi, R. Basu, M. Islam, K.S. Kolekar and A. Mehra,Galilean gauge theories from null reductions, JHEP 04 (2022) 176 [2201.12629]

  2. [10]

    Lambert and J

    N. Lambert and J. Smith,Non-relativistic intersecting branes, Newton-Cartan geometry and AdS/CFT, JHEP 07 (2024) 224 [2405.06552]

  3. [11]

    Hartong and J

    J. Hartong and J. Musaeus,Toward a covariant framework for post-Newtonian expansions for radiative sources, Phys. Rev. D109 (2024) 124058 [2311.07546]

  4. [12]

    Oling and Z

    G. Oling and Z. Yan,Aspects of Nonrelativistic Strings, Front. in Phys.10 (2022) 832271 [2202.12698]

  5. [13]

    Gomis and H

    J. Gomis and H. Ooguri,Nonrelativistic closed string theory, J. Math. Phys.42 (2001) 3127 [hep-th/0009181]

  6. [14]

    Danielsson, A

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

  7. [15]

    Klebanov and J.M

    I.R. Klebanov and J.M. Maldacena,(1+1)-dimensional NCOS and its U(N) gauge theory dual, Adv. Theor. Math. Phys.4 (2000) 283 [hep-th/0006085]

  8. [16]

    Danielsson, A

    U.H. Danielsson, A. Guijosa and M. Kruczenski,Newtonian gravitons and d-brane collective coordinates in wound string theory, JHEP 03 (2001) 041 [hep-th/0012183]

  9. [17]

    Gomis, J

    J. Gomis, J. Gomis and K. Kamimura,Non-relativistic superstrings: A New soluble sector of AdS(5) x S**5, JHEP 12 (2005) 024 [hep-th/0507036]

  10. [18]

    Christensen, J

    M.H. Christensen, J. Hartong, N.A. Obers and B. Rollier,Torsional Newton-Cartan Geometry and Lifshitz Holography, Phys. Rev. D89 (2014) 061901 [1311.4794]

  11. [19]

    Christensen, J

    M.H. Christensen, J. Hartong, N.A. Obers and B. Rollier,Boundary Stress-Energy Tensor and Newton-Cartan Geometry in Lifshitz Holography, JHEP 01 (2014) 057 [1311.6471]

  12. [20]

    Hartong, E

    J. Hartong, E. Kiritsis and N.A. Obers,Lifshitz space–times for Schrödinger holography, Phys. Lett. B746 (2015) 318 [1409.1519]. – 30 –

  13. [21]

    Harmark, J

    T. Harmark, J. Hartong and N.A. Obers,Nonrelativistic strings and limits of the AdS/CFT correspondence, Phys. Rev. D96 (2017) 086019 [1705.03535]

  14. [22]

    Harmark, J

    T. Harmark, J. Hartong, L. Menculini, N.A. Obers and Z. Yan,Strings with Non-Relativistic Conformal Symmetry and Limits of the AdS/CFT Correspondence, JHEP 11 (2018) 190 [1810.05560]

  15. [23]

    Gallegos, U

    A.D. Gallegos, U. Gürsoy and N. Zinnato,Torsional Newton Cartan gravity from non-relativistic strings, JHEP 09 (2020) 172 [1906.01607]

  16. [24]

    Andringa, E

    R. Andringa, E. Bergshoeff, J. Gomis and M. de Roo,’Stringy’ Newton-Cartan Gravity, Class. Quant. Grav.29 (2012) 235020 [1206.5176]

  17. [25]

    Bergshoeff, J

    E. Bergshoeff, J. Gomis and Z. Yan,Nonrelativistic String Theory and T-Duality, JHEP 11 (2018) 133 [1806.06071]

  18. [26]

    Bergshoeff, J

    E.A. Bergshoeff, J. Gomis, J. Rosseel, C. Şimşek and Z. Yan,String Theory and String Newton-Cartan Geometry, J. Phys. A53 (2020) 014001 [1907.10668]

  19. [27]

    Bergshoeff, K.T

    E.A. Bergshoeff, K.T. Grosvenor, C. Simsek and Z. Yan,An Action for Extended String Newton-Cartan Gravity, JHEP 01 (2019) 178 [1810.09387]

  20. [28]

    Klusoň,Remark About Non-Relativistic String in Newton-Cartan Background and Null Reduction, JHEP 05 (2018) 041 [1803.07336]

    J. Klusoň,Remark About Non-Relativistic String in Newton-Cartan Background and Null Reduction, JHEP 05 (2018) 041 [1803.07336]

  21. [29]

    Bergshoeff, J

    E.A. Bergshoeff, J. Lahnsteiner, L. Romano, J. Rosseel and C. Şimşek,A non-relativistic limit of NS-NS gravity, JHEP 06 (2021) 021 [2102.06974]

  22. [30]

    Yan,Torsional deformation of nonrelativistic string theory, JHEP 09 (2021) 035 [2106.10021]

    Z. Yan,Torsional deformation of nonrelativistic string theory, JHEP 09 (2021) 035 [2106.10021]

  23. [31]

    Gomis, J

    J. Gomis, J. Oh and Z. Yan,Nonrelativistic String Theory in Background Fields, JHEP 10 (2019) 101 [1905.07315]

  24. [32]

    Harmark, J

    T. Harmark, J. Hartong, L. Menculini, N.A. Obers and G. Oling,Relating non-relativistic string theories, JHEP 11 (2019) 071 [1907.01663]

  25. [33]

    Hartong and E

    J. Hartong and E. Have,Nonrelativistic Expansion of Closed Bosonic Strings, Phys. Rev. Lett. 128 (2022) 021602 [2107.00023]

  26. [34]

    Hartong and E

    J. Hartong and E. Have,Nonrelativistic approximations of closed bosonic string theory, JHEP 02 (2023) 153 [2211.01795]

  27. [35]

    Bagchi, A

    A. Bagchi, A. Banerjee, J. Hartong, E. Have, K.S. Kolekar and M. Mandlik,Strings near black holes are Carrollian, Phys. Rev. D110 (2024) 086009 [2312.14240]

  28. [36]

    Bagchi, A

    A. Bagchi, A. Banerjee, J. Hartong, E. Have and K.S. Kolekar,Strings near black holes are Carrollian. Part II, JHEP 11 (2024) 024 [2407.12911]

  29. [37]

    Fontanella and J.M

    A. Fontanella and J.M. Nieto García,Constructing nonrelativistic AdS5/CFT4 holography, Phys. Rev. D111 (2025) 026003 [2403.02379]

  30. [38]

    Blair, J

    C.D.A. Blair, J. Lahnsteiner, N.A. Obers and Z. Yan,Unification of Decoupling Limits in String and M Theory, Phys. Rev. Lett.132 (2024) 161603 [2311.10564]

  31. [39]

    Gomis and Z

    J. Gomis and Z. Yan,Worldsheet formalism for decoupling limits in string theory, JHEP 07 (2024) 102 [2311.10565]

  32. [40]

    Blair, J

    C.D.A. Blair, J. Lahnsteiner, N.A. Obers and Z. Yan,Matrix theory reloaded: a BPS road to holography, JHEP 02 (2025) 024 [2410.03591]. – 31 –

  33. [41]

    Park and S

    J.-H. Park and S. Sugimoto,String Theory and non-Riemannian Geometry, Phys. Rev. Lett. 125 (2020) 211601 [2008.03084]

  34. [42]

    Blair, G

    C.D.A. Blair, G. Oling and J.-H. Park,Non-Riemannian isometries from double field theory, JHEP 04 (2021) 072 [2012.07766]

  35. [43]

    Blair,A worldsheet supersymmetric Newton-Cartan string, JHEP 10 (2019) 266 [1908.00074]

    C.D.A. Blair,A worldsheet supersymmetric Newton-Cartan string, JHEP 10 (2019) 266 [1908.00074]

  36. [44]

    Bergshoeff, J

    E. Bergshoeff, J. Lahnsteiner, L. Romano and J. Rosseel,The supersymmetric Neveu-Schwarz branes of non-relativistic string theory, JHEP 08 (2022) 218 [2204.04089]

  37. [45]

    Guijosa,On the Underlying Nonrelativistic Nature of Relativistic Holography, 2502.03031

    A. Guijosa,On the Underlying Nonrelativistic Nature of Relativistic Holography, 2502.03031

  38. [46]

    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 [1012.3982]

  39. [47]

    Zarembo,Integrability in Sigma-Models, 1712.07725

    K. Zarembo,Integrability in Sigma-Models, 1712.07725

  40. [48]

    Kluson,Note About Integrability of Non-Relativistic String, Mod

    J. Kluson,Note About Integrability of Non-Relativistic String, Mod. Phys. Lett. A34 (2019) 1950132 [1705.10951]

  41. [49]

    Roychowdhury,Lax pairs for string Newton Cartan geometry, Nucl

    D. Roychowdhury,Lax pairs for string Newton Cartan geometry, Nucl. Phys. B 954 (2020) 114990 [1904.06485]

  42. [50]

    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]

  43. [51]

    Roychowdhury,Nonrelativistic pulsating strings, JHEP 09 (2019) 002 [1907.00584]

    D. Roychowdhury,Nonrelativistic pulsating strings, JHEP 09 (2019) 002 [1907.00584]

  44. [52]

    Roychowdhury,Nonrelativistic spinning strings, JHEP 11 (2020) 044 [2008.08895]

    D. Roychowdhury,Nonrelativistic spinning strings, JHEP 11 (2020) 044 [2008.08895]

  45. [53]

    Roychowdhury,Multispin magnons from Spin-Matrix strings onAdS5×S5, Phys

    D. Roychowdhury,Multispin magnons from Spin-Matrix strings onAdS5×S5, Phys. Lett. B 818 (2021) 136389 [2010.05179]

  46. [54]

    Roychowdhury,Decoding the Spin-Matrix limit of strings onAdS5×S5, Phys

    D. Roychowdhury,Decoding the Spin-Matrix limit of strings onAdS5×S5, Phys. Lett. B 820 (2021) 136499 [2101.06513]

  47. [55]

    Roychowdhury,Semiclassical dynamics for torsional Newton-Cartan strings, Nucl

    D. Roychowdhury,Semiclassical dynamics for torsional Newton-Cartan strings, Nucl. Phys. B 958 (2020) 115132 [1911.10473]

  48. [56]

    Roychowdhury,Newton-Cartan D0 branes fromD1 branes and integrability, JHEP 06 (2020) 120 [2004.03427]

    D. Roychowdhury,Newton-Cartan D0 branes fromD1 branes and integrability, JHEP 06 (2020) 120 [2004.03427]

  49. [57]

    Roychowdhury,Nonrelativistic strings onR×S2 and integrable systems, Nucl

    D. Roychowdhury,Nonrelativistic strings onR×S2 and integrable systems, Nucl. Phys. B 961 (2020) 115220 [2003.02613]

  50. [58]

    Arutyunov, S

    G. Arutyunov, S. Frolov, J. Russo and A.A. Tseytlin,Spinning strings in AdS(5) x S**5 and integrable systems, Nucl. Phys. B 671 (2003) 3 [hep-th/0307191]

  51. [59]

    Arutyunov, J

    G. Arutyunov, J. Russo and A.A. Tseytlin,Spinning strings in AdS(5) x S**5: New integrable system relations, Phys. Rev. D69 (2004) 086009 [hep-th/0311004]

  52. [60]

    C. Ahn, P. Bozhilov and R.C. Rashkov,Neumann-Rosochatius integrable system for strings on AdS(4) x CP**3, JHEP 09 (2008) 017 [0807.3134]

  53. [61]

    Hernández and J.M

    R. Hernández and J.M. Nieto,Spinning strings inAdS3×S3 with NS–NS flux, Nucl. Phys. B 888 (2014) 236 [1407.7475]

  54. [62]

    Hernandez and J.M

    R. Hernandez and J.M. Nieto,Elliptic solutions in the Neumann–Rosochatius system with mixed flux, Phys. Rev. D91 (2015) 126006 [1502.05203]. – 32 –

  55. [63]

    Arutyunov, M

    G. Arutyunov, M. Heinze and D. Medina-Rincon,Integrability of theη-deformed Neumann–Rosochatius model, J. Phys. A50 (2017) 035401 [1607.05190]

  56. [64]

    Hernandez and J.M

    R. Hernandez and J.M. Nieto,Spinning strings in theη-deformed Neumann-Rosochatius system, Phys. Rev. D96 (2017) 086010 [1707.08032]

  57. [65]

    Hernández, J.M

    R. Hernández, J.M. Nieto and R. Ruiz,Pulsating strings with mixed three-form flux, JHEP 04 (2018) 078 [1803.03078]

  58. [66]

    Hernández, J.M

    R. Hernández, J.M. Nieto and R. Ruiz,Minimal surfaces with mixed three-form flux, Phys. Rev. D 99 (2019) 086003 [1811.08294]

  59. [67]

    Nieto and R

    J.M. Nieto and R. Ruiz,One-loop quantization of rigid spinning strings inAdS3×S3×T 4 with mixed flux, JHEP 07 (2018) 141 [1804.10477]

  60. [68]

    Chakraborty and K.L

    A. Chakraborty and K.L. Panigrahi,Neumann-Rosochatius system for strings in ABJ Model, JHEP 12 (2019) 024 [1909.12632]

  61. [69]

    Hernández and R

    R. Hernández and R. Ruiz,Double Yang-Baxter deformation of spinning strings, JHEP 06 (2020) 115 [2003.05724]

  62. [70]

    Chakraborty and K.L

    A. Chakraborty and K.L. Panigrahi,Neumann-Rosochatius system for (m,n) string in AdS3×S3 with mixed flux, Eur. Phys. J. C81 (2021) 281 [2008.05139]

  63. [71]

    Chakraborty, R.R

    A. Chakraborty, R.R. Nayak, P. Pandit and K.L. Panigrahi,Neumann-Rosochatius system for rotating strings in with flux, JHEP 12 (2022) 059 [2209.07379]

  64. [72]

    Chakraborty, N

    A. Chakraborty, N. Padhi, P. Pandit and K.L. Panigrahi,Neumann-Rosochatius system for strings on I-brane, JHEP 12 (2022) 022 [2209.09933]

  65. [73]

    Hernandez, R

    R. Hernandez, R. Ruiz and K. Sfetsos,Spinning strings:λ-deformation and non-Abelian T-dual limit, Nucl. Phys. B 991 (2023) 116199 [2206.13551]

  66. [74]

    Hofman and J.M

    D.M. Hofman and J.M. Maldacena,Giant Magnons, J. Phys. A39 (2006) 13095 [hep-th/0604135]

  67. [75]

    Bidussi, T

    L. Bidussi, T. Harmark, J. Hartong, N.A. Obers and G. Oling,Torsional string Newton-Cartan geometry for non-relativistic strings, JHEP 02 (2022) 116 [2107.00642]

  68. [76]

    Fontanella and J.M

    A. Fontanella and J.M. Nieto García,Light-cone gauge in non-relativistic AdS5×S5 string theory, JHEP 11 (2023) 053 [2102.00008]

  69. [77]

    Fontanella and J.M.N

    A. Fontanella and J.M.N. García,Classical string solutions in non-relativistic: closed and twisted sectors, J. Phys. A55 (2022) 085401 [2109.13240]

  70. [78]

    Gubser, I.R

    S.S. Gubser, I.R. Klebanov and A.M. Polyakov,A Semiclassical limit of the gauge / string correspondence, Nucl. Phys. B 636 (2002) 99 [hep-th/0204051]

  71. [79]

    Floratos, G

    E. Floratos, G. Georgiou and G. Linardopoulos,Large-Spin Expansions of GKP Strings, JHEP 03 (2014) 018 [1311.5800]

  72. [80]

    Beisert,The SU(2|2) dynamic S-matrix, Adv

    N. Beisert,The SU(2|2) dynamic S-matrix, Adv. Theor. Math. Phys.12 (2008) 945 [hep-th/0511082]

  73. [81]

    Roychowdhury,Nonrelativistic giant magnons from Newton Cartan strings, JHEP 02 (2020) 109 [2001.01061]

    D. Roychowdhury,Nonrelativistic giant magnons from Newton Cartan strings, JHEP 02 (2020) 109 [2001.01061]

  74. [82]

    Berenstein, J.M

    D.E. Berenstein, J.M. Maldacena and H.S. Nastase,Strings in flat space and pp waves from N=4 superYang-Mills, JHEP 04 (2002) 013 [hep-th/0202021]. – 33 –

  75. [83]

    Voros,Semi-classical approximations, inAnnales de l’institut Henri Poincaré

    A. Voros,Semi-classical approximations, inAnnales de l’institut Henri Poincaré. Section A, Physique Théorique, vol. 24, pp. 31–90, 1976

  76. [84]

    Minahan,Circular semiclassical string solutions on AdS(5) x S(5), Nucl

    J.A. Minahan,Circular semiclassical string solutions on AdS(5) x S(5), Nucl. Phys. B 648 (2003) 203 [hep-th/0209047]

  77. [85]

    Beccaria, G

    M. Beccaria, G. Macorini and A. Tirziu,Semiclassical short strings inAdS5xS5, Theor. Math. Phys. 167 (2011) 695 [1009.5182]

  78. [86]

    H.-Y. Chen, N. Dorey and K. Okamura,Dyonic giant magnons, JHEP 09 (2006) 024 [hep-th/0605155]

  79. [87]

    Pohlmeyer,Integrable Hamiltonian Systems and Interactions Through Quadratic Constraints, Commun

    K. Pohlmeyer,Integrable Hamiltonian Systems and Interactions Through Quadratic Constraints, Commun. Math. Phys.46 (1976) 207

  80. [88]

    Kruczenski,Spiky strings and single trace operators in gauge theories, JHEP 08 (2005) 014 [hep-th/0410226]

    M. Kruczenski,Spiky strings and single trace operators in gauge theories, JHEP 08 (2005) 014 [hep-th/0410226]

  81. [89]

    Jevicki, K

    A. Jevicki, K. Jin, C. Kalousios and A. Volovich,Generating AdS String Solutions, JHEP 03 (2008) 032 [0712.1193]

  82. [90]

    De Vega and N.G

    H.J. De Vega and N.G. Sanchez,Exact integrability of strings in D-Dimensional De Sitter space-time, Phys. Rev. D47 (1993) 3394

  83. [91]

    Combes, H.J

    F. Combes, H.J. de Vega, A.V. Mikhailov and N.G. Sanchez,Multistring solutions by soliton methods in de Sitter space-time, Phys. Rev. D50 (1994) 2754 [hep-th/9310073]

  84. [92]

    Larsen and N.G

    A.L. Larsen and N.G. Sanchez,Sinh-Gordon, cosh-Gordon and Liouville equations for strings and multistrings in constant curvature space-times, Phys. Rev. D54 (1996) 2801 [hep-th/9603049]

  85. [93]

    Harmark and M

    T. Harmark and M. Orselli,Spin Matrix Theory: A quantum mechanical model of the AdS/CFT correspondence, JHEP 11 (2014) 134 [1409.4417]

  86. [94]

    Hartong and E

    J. Hartong and E. Have,Non-relativistic expansion of open strings and D-branes, JHEP 09 (2024) 087 [2407.05985]

  87. [95]

    Uhlenbeck,Equivariant harmonic maps into spheres, inHarmonic Maps, R.J

    K.K. Uhlenbeck,Equivariant harmonic maps into spheres, inHarmonic Maps, R.J. Knill, M. Kalka and H.C.J. Sealey, eds., (Berlin, Heidelberg), pp. 146–158, Springer Berlin Heidelberg, 1982. – 34 –

Pith tools

Reviewed August 16, 2026 · model on record in the stance chip above.