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REVIEW 3 major objections 3 minor 99 references

Covering space maps for $n$-point functions with three long twists

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

Pith's one-line read The paper constructs the general class of genus-zero covering space maps for correlators with three arbitrary-length single-cycle twists and any number of twist-2 insertions.

desk verdict Solid covering-map construction for three long twists plus twist-2 clouds; the closed-form correlators are conditional on unproven discriminant identities that need a proof or numerical check. read the letter →

arxiv 2507.12512 v1 pith:LVJXVJLA submitted 2025-07-16 hep-th

classification hep-th
keywords symmetricproductorbifoldCFTcoveringspacemapstwistoperatorsn-pointfunctionsJacobipolynomialsWronskianOPElimitsalgebraicvarieties
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 constructs the general genus-zero covering space maps needed to compute correlation functions in symmetric product orbifold CFTs when the correlator contains three single-cycle twist operators of arbitrary lengths and any number of twist-2 insertions. The maps are written as ratios of finite sums over Jacobi polynomials, with $\Delta N+1$ coefficients $b_N$ that scale to a common factor and therefore live naturally in $\mathbb{CP}^{\Delta N}$. From these maps the paper extracts the Wronskian, the OPE limits, and the coefficients entering the standard $n$-point function formula, and in the $\Delta N=1,2$ cases writes the four- and five-point functions of bare twists in closed form. The paper's central claim is that this family exhausts all group-theoretically allowed ramifications for this class of correlators, up to analytic continuation.

What carries the argument

The load-bearing object is the rational covering map together with its Wronskian. The map is written in three equivalent forms, adapted to $t=0$, $t=1$ and $t=\infty$, all built from the same sums of Jacobi polynomials with coefficients $b_N$. The Wronskian factorization $W=t^{N_{\min}}(t-1)^{n_1+n_3-N_{\max}-1}Q(t)$ makes the ramification structure visible: the fixed powers encode the three long single-cycle twists, and the degree-$\Delta N$ polynomial $Q$ encodes the cloud of twist-2 insertions. For $\Delta N\le 2$ the polynomial $Q$ is determined in closed form from OPE-limit data; for larger $\Delta N$ the paper provides an algorithmic $\Delta N$-step construction. The scaling symmetry $b_N\to\lambda b_N$ makes the coefficient space naturally $\mathbb{CP}^{\Delta N}$.

What would settle it

Choose a generic non-limiting point in the $\Delta N=2$ parameter space, for example $n_1=1$, $n_3=4$, $N_{\min}=1$, $N_{\max}=3$ with random nonzero $b_N$, compute the coefficients of $f_1$ and its discriminant numerically, and compare with (4.19); a single mismatch at such a point would show the reverse-engineered discriminant is incomplete. The analogous check of (4.16) at a $\Delta N=1$ point would settle the closed-form four-point function.

Watch

Extended reading notes

Core claim

Formally, the central claim is that the maps (2.27), equivalently (2.28) and (2.29), form the complete class of genus-zero covering space maps for correlators with three twists of arbitrary lengths and any number of twist-2 insertions. The map is $z(t)=f_2(t)/f_1(t)$, where $f_1$ and $f_2$ are the finite Jacobi-polynomial sums of (2.22); its Wronskian factorizes as $W=t^{N_{\min}}(t-1)^{n_1+n_3-N_{\max}-1}Q(t)$, with the degree-$\Delta N$ polynomial $Q$ locating the cloud of twist-2 insertions. The coefficients $b_N$ parameterize $\mathbb{CP}^{\Delta N}$, matching the number of cross ratios of a $(3+\Delta N)$-point function. Section 2.3 argues that every group-theoretically allowed choice of $r_0,r_1,r_\infty,r_c$ is realized, up to transport. For $\Delta N=1,2$ the paper evaluates all map data needed by formula (1.9) and obtains closed-form four- and five-point functions of bare twists; the OPE limits in which cloud points collide are shown to be algebraic subvarieties of $\mathbb{CP}^{\Delta N}$.

Load-bearing premise

The load-bearing premise is that the reverse-engineered discriminant formulas for $f_1$ in (4.16) and (4.19) hold for all values of the coefficients $b_N$; the paper fixes their powers and coefficients by matching limiting cases rather than proving them, so a failure at a generic parameter point would invalidate the stated closed-form correlators even if the covering-map construction itself remains correct.

Editorial extensions

If this is right

  • The same $b_N$ parameters that fix the positions of the twist-2 insertions also select which OPE channel is realized when two ramified points collide, so the correlation functions' singularity structure is visible directly in the map data.
  • For $\Delta N=1$, the four-point function of three long twists plus one twist-2 insertion is obtained in closed form, including the discriminant of $f_1$.
  • For $\Delta N=2$, the five-point function is obtained in closed form; the two cloud points can merge either into a twist-3 operator or into an untwisted twist-down limit, each governed by a homogeneous polynomial constraint on the $b_N$.
  • For $\Delta N\ge 3$, the paper's algorithmic Wronskian computation gives the map data needed for higher-point functions without requiring closed-form discriminants.
  • The resulting bare-twist correlators provide new data for testing AdS$_3$/CFT$_2$ dualities and for conformal perturbation theory along exactly marginal twist-2 deformations.

Reading between the lines

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

  • Inference: The reverse-engineered discriminant formulas (4.16) and (4.19) should be tested numerically at generic $b_N$ before the closed-form four- and five-point functions are used in applications; the paper itself does not prove them for all parameters.
  • Inference: If those discriminant identities fail for some $b_N$, the covering map construction and the general Wronskian algorithm survive; only the closed correlator expressions would need revision.
  • Inference: The same Jacobi-sum construction is likely to generate maps for correlators with more than three long twists by iterating the hypergeometric-window limit, although the paper does not pursue that step.
  • Inference: Rewriting conformal perturbation theory integrals in the $\mathbb{CP}^{\Delta N}$ coordinates of the $b_N$ could absorb the sum over transport-equivalent preimage maps into a single integration, as the paper hints in its discussion of connected Hurwitz numbers.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 3 minor

Summary. The paper constructs genus-zero covering space maps for symmetric product orbifold correlators with three long single-cycle twists and an arbitrary number of twist-2 insertions. The maps are written as ratios of sums of Jacobi polynomials with coefficients b_N valued in CP^{ΔN}, and their Wronskian is shown to have the form t^{N_min}(t-1)^{n_1+n_3-N_max-1} Q(t), where the zeros of Q locate the twist-2 cloud. The authors derive OPE limit constraints as algebraic varieties in CP^{ΔN}, and then compute the map data needed for the n-point function formula (1.9). For ΔN=1 and ΔN=2 they present closed-form expressions for the four- and five-point functions, with the main new ingredient being discriminant formulas for f_1 given in (4.16) and (4.19).

Significance. If the closed-form claims hold, the paper is a substantial advance: it provides explicit higher-point correlator data for symmetric product orbifolds beyond known three- and four-point results, with potential applications to conformal perturbation theory and to AdS_3/CFT_2 tests. The map construction itself is well supported: the Wronskian form is tied to Jacobi identities proved in Appendix B, the ramification bounds in Appendix D are carefully argued, and the ΔN=1 case is checked against the Heun-function parameterization of [92]. The approach is not circular: the b_N parameters are genuine degrees of freedom rather than constants fitted to reproduce target correlators. The principal gap is the unproven, reverse-engineered discriminant identities (4.16) and (4.19), which are load-bearing for the stated closed-form correlators.

major comments (3)
  1. [Section 4, after Eq. (4.13), Eqs. (4.16) and (4.19)] The closed-form four- and five-point functions in the ΔN=1,2 cases rest on the discriminant formulas (4.16) and (4.19), which the text explicitly states were 'reverse engineered' by checking limiting cases and fixing powers and coefficients, rather than proved for generic b_N. These identities enter the product over unramified images of infinity (4.13) and therefore the correlator (4.1). A single incorrect exponent, factorial prefactor, or denominator factor would invalidate the stated closed-form correlators even though the underlying map construction may be sound. I request either a proof of (4.16) and (4.19) for generic b_N or an independent verification, for example randomized polynomial checks at several parameter values, together with an explicit statement of the status of these identities.
  2. [Section 4, Eqs. (4.16) and (4.19), and the OPE denominators] Even accepting the structural argument that every zero of Disc(f_1) is a zero of Res(Q,f_1), the factorization pattern alone does not determine the precise powers, factorial prefactors, and the denominator factors g(0,↓), g(1,↓), and g(c,↓) appearing in (4.16) and (4.19). These denominators can vanish in OPE limits, so the claimed cancellations must be justified separately; without that, the singularity structure of the correlators is not established. The paper should provide the missing derivation or at least an explicit verification of the identities, including the OPE-limit cases where the denominators vanish.
  3. [Section 2.3, Eqs. (2.33)-(2.38), and Section 5] The abstract and Section 2.3 claim that the maps (2.27) constitute the 'general class' of covering space maps for three long twists plus twist-2 insertions. What is proved is that every group-theoretically allowed tuple of ramifications can be realized by some choice of n_1, n_3, N_min, N_max and b_N. The statement that this is a complete set 'up to transport' is explicitly conditional on the conjecture in [47]. If completeness is part of the central claim, the paper should either prove the transport/completeness statement or qualify the word 'general' in the abstract and in the 'Generality of the maps' section.
minor comments (3)
  1. [Abstract and Section 1] The abstract should state explicitly that the computed correlators are the genus-zero connected leading large-N contributions, since the paper restricts to spherical covering surfaces in Section 1.
  2. [Eqs. (1.16) and (4.6)] The symbol A_0 is used both for the overall Wronskian constant in (1.16) and for the leading coefficient of Q(t) in (4.6); these are related but not identical, and the reuse is confusing. Please rename one of them.
  3. [Eqs. (4.16) and (4.19)] The product ranges in (4.16) and (4.19) should be checked for edge cases such as n_1=1 or n_3=N_min+1, where some upper limits become zero or negative; if these cases are excluded, the allowed parameter ranges should be stated explicitly.

Circularity Check

0 steps flagged · score 2.0 of 10

No significant circularity: the covering-map construction is self-contained, and the reverse-engineered discriminant formulas are an admitted gap rather than a circular step.

full rationale

The central construction of the maps (2.27) is self-contained and does not reduce to its own output. The maps are obtained by taking a regulated limit of hypergeometric sums following the external Heun-function construction [92], and the Wronskian form (2.31), the ramification data (2.30), and the OPE-limit constraints are verified directly through Jacobi-polynomial identities proved in Appendix B, not by fitting correlators. The claimed generality over all group-theoretically allowed ramifications is argued from ramification subadditivity in Appendix D, independently of the n-point function formulas. The correlator formula (1.9)/(4.1) is imported from the external reference [47], not from the authors' own prior work. The coefficients b_N are genuine free parameters valued in CP^{Delta N}, not fitted constants renamed as predictions; the OPE limits are homogeneous algebraic constraints derived from the map structure. Self-citations in the bibliography (e.g., [59,60,86,89,90]) are used for context, dressing techniques, or motivation and are not load-bearing for the new map construction. The only admitted reverse-engineered ingredient is the discriminant of f_1, given in (4.16) and (4.19): the paper states 'we simply reverse engineer Disc(f1) for the specific cases at hand' and fixes powers and coefficients by checking limiting cases where f1 reduces to a single Jacobi polynomial whose discriminants are known from [96]. That is an unproven intermediate identity, and an error there would invalidate the closed-form four- and five-point correlator expressions, but it is not a circular reduction: the covering map itself and the Wronskian data do not depend on it. No step in the paper fits a parameter to a subset of data and then presents a closely related quantity as an independent prediction, and no uniqueness claim is imported solely from the authors' own prior work. The score is therefore low; the reverse-engineered discriminant is best treated as a correctness risk to be settled by a direct polynomial check, not as circular reasoning.

Assumptions & free parameters 1 free parameters · 4 assumptions · 0 invented entities

The central map construction uses no fitted hidden constants; the b_N are the natural coordinates of the moduli space of maps, invariant under overall scaling. It relies on standard Jacobi/hypergeometric identities and on the Dei-Eberhardt formula expressing correlators in terms of map data. The completeness 'up to transport' assumes an unproved claim from [47].

free parameters (1)
  • b_N (N = N_min ... N_max)
    The ΔN+1 coefficients of the Jacobi polynomial sums in the covering map (2.27). They are the natural moduli of the maps, valued in CP^ΔN by overall scaling; they are not fitted to data but parameterize the positions of the twist-2 insertions.
assumptions (4)
  • domain assumption The n-point function formula (1.9) from Dei-Eberhardt [47] expresses correlators in terms of map data (a_i, C_rho)
    Used throughout Section 4 to convert covering map coefficients into correlation functions; cited from prior literature.
  • domain assumption All sphere covering space maps are connected by analytic continuation (transport), so a complete set up to transport gives all maps [47]
    Invoked in Section 2.3 to claim completeness of the constructed maps 'up to transport'.
  • standard math Standard Jacobi polynomial identities and hypergeometric identities (appendix A, B, [99])
    Used to derive the map forms and OPE limits; these are external mathematical facts.
  • standard math The solution expansion of Heun equations in [92] is a valid starting point (finite sums of hypergeometric functions with recurrence truncation)
    Used in Section 2.2 to generate sums over Jacobi polynomials before taking a limit.

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Pith. "Pith review of Covering space maps for $n$-point functions with three long twists." pith.science (2026). https://pith.science/paper/LVJXVJLA

@misc{pith2026250712512,
  author       = {Pith},
  title        = {Pith review of: Covering space maps for $n$-point functions with three long twists},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/LVJXVJLA}},
  note         = {Machine review of arXiv:2507.12512}
}
abstract

We consider correlation functions in symmetric product orbifold CFTs on the sphere, focusing on the case where all operators are single-cycle twists, and the covering surface is also a sphere. We directly construct the general class of covering space maps where there are three twists of arbitrary lengths, along with any number of twist-2 insertions. These are written as a ratio of sums of Jacobi polynomials with $\Delta N+1$ coefficients $b_N$. These coefficients have a scaling symmetry $b_N\rightarrow \lambda b_N$, making them naturally valued in $\mathbb{CP}^{\Delta N}$. We explore limits where various ramified points on the cover approach each other, which are understood as crossing channel specific OPE limits, and find that these limits are defined by algebraic varieties of $\mathbb{CP}^{\Delta N}$. We compute the expressions needed to calculate the group element representative correlation functions for bare twists. Specializing to the cases $\Delta N=1,2$, we find closed form for these expressions which define four- and five-point functions of bare twists.

Figures

Figures reproduced from arXiv: 2507.12512 by the authors.

Figure 1
Figure 1. The ranges of N for the different cases 1-3. 1. N ≥ n3 such that P −(n1+n3−N),N+1 n3−N−1 is set to 0 in (B.2) (similarly in (B.1)) (a) N ≥ n1 + n3 (b) n3 ≤ N < n1 + n3 2. N < n1 such that P (n1+n3−N),−(N+1) N−n1 is set to 0 in (B.2) (similarly in (B.1)) (a) 0 ≤ N + 1 ≤ n1 (b) N + 1 < 0 3. n1 ≤ N < n3 such that all Jacobi polynomials are present in (B.1) and (B.2) The main cases above are motivated by the absence of … view at source ↗

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Works this paper leans on

99 extracted references · 20 canonical work pages

  1. [92]

    Expansions of the Solutions of the General Heun Equation Governed by Two-Term Recurrence Relations for Coefficients,

    T. A. Ishkhanyan, T. A. Shahverdyan, and A. M. Ishkhanyan, “Expansions of the Solutions of the General Heun Equation Governed by Two-Term Recurrence Relations for Coefficients,”Adv. High Energy Phys.2018(2018) 4263678,arXiv:1403.7863 [math.CA]

  2. [47]

    Correlators of the symmetric product orbifold,

    A. Dei and L. Eberhardt, “Correlators of the symmetric product orbifold,”JHEP01(2020) 108, arXiv:1911.08485 [hep-th]

  3. [1]

    Strings on Orbifolds,

    L. J. Dixon, J. A. Harvey, C. Vafa, and E. Witten, “Strings on Orbifolds,”Nucl. Phys. B261 (1985) 678–686

  4. [2]

    Strings on Orbifolds. 2.,

    L. J. Dixon, J. A. Harvey, C. Vafa, and E. Witten, “Strings on Orbifolds. 2.,”Nucl. Phys. B274 (1986) 285–314

  5. [3]

    The Operator Algebra of Orbifold Models,

    R. Dijkgraaf, C. Vafa, E. P. Verlinde, and H. L. Verlinde, “The Operator Algebra of Orbifold Models,”Commun. Math. Phys.123(1989) 485

  6. [4]

    Gas of d-branes and Hagedorn density of BPS states,

    C. Vafa, “Gas of d-branes and Hagedorn density of BPS states,”Nucl. Phys. B463(1996) 415–419,arXiv:hep-th/9511088

  7. [5]

    Instantons on D-branes,

    C. Vafa, “Instantons on D-branes,”Nucl. Phys. B463(1996) 435–442,arXiv:hep-th/9512078

  8. [6]

    Microscopic origin of the Bekenstein-Hawking entropy,

    A. Strominger and C. Vafa, “Microscopic origin of the Bekenstein-Hawking entropy,”Phys. Lett. B379(1996) 99–104,arXiv:hep-th/9601029

Show all 99 references
  1. [7]

    Elliptic genera of symmetric products and second quantized strings,

    R. Dijkgraaf, G. W. Moore, E. P. Verlinde, and H. L. Verlinde, “Elliptic genera of symmetric products and second quantized strings,”Commun. Math. Phys.185(1997) 197–209, arXiv:hep-th/9608096 [hep-th]

  2. [8]

    The Large N limit of superconformal field theories and supergravity,

    J. M. Maldacena, “The Large N limit of superconformal field theories and supergravity,”Int. J. Theor. Phys.38(1999) 1113–1133,arXiv:hep-th/9711200 [hep-th]. [Adv. Theor. Math. Phys.2,231(1998)]

  3. [9]

    Comments on string theory on AdS(3),

    A. Giveon, D. Kutasov, and N. Seiberg, “Comments on string theory on AdS(3),”Adv. Theor. Math. Phys.2(1998) 733–782,arXiv:hep-th/9806194

  4. [10]

    String theory on AdS 3 ×S 3 ×S 3 ×S 1,

    S. Elitzur, O. Feinerman, A. Giveon, and D. Tsabar, “String theory on AdS 3 ×S 3 ×S 3 ×S 1,” Phys. Lett.B449(1999) 180–186,arXiv:hep-th/9811245 [hep-th]

  5. [11]

    Large N elliptic genus and AdS/CFT correspondence,

    J. de Boer, “Large N elliptic genus and AdS/CFT correspondence,”JHEP05(1999) 017, arXiv:hep-th/9812240 [hep-th]

  6. [12]

    Counting BPS black holes in toroidal Type II string theory,

    J. M. Maldacena, G. W. Moore, and A. Strominger, “Counting BPS black holes in toroidal Type II string theory,”arXiv:hep-th/9903163 [hep-th]. 57

  7. [13]

    The D1/D5 system and singular CFT,

    N. Seiberg and E. Witten, “The D1/D5 system and singular CFT,”JHEP04(1999) 017, arXiv:hep-th/9903224 [hep-th]

  8. [14]

    AdS/CFT dualities involving large 2DN= 4 superconformal symmetry,

    J. de Boer, A. Pasquinucci, and K. Skenderis, “AdS/CFT dualities involving large 2DN= 4 superconformal symmetry,”Adv. Theor. Math. Phys.3(1999) 577–614,arXiv:hep-th/9904073 [hep-th]

  9. [15]

    U(1) charges and moduli in the D1 - D5 system,

    F. Larsen and E. J. Martinec, “U(1) charges and moduli in the D1 - D5 system,”JHEP06 (1999) 019,arXiv:hep-th/9905064 [hep-th]

  10. [16]

    D1 / D5 moduli in SCFT and gauge theory, and Hawking radiation,

    J. R. David, G. Mandal, and S. R. Wadia, “D1 / D5 moduli in SCFT and gauge theory, and Hawking radiation,”Nucl. Phys. B564(2000) 103–127,arXiv:hep-th/9907075

  11. [17]

    A Black hole Farey tail,

    R. Dijkgraaf, J. M. Maldacena, G. W. Moore, and E. P. Verlinde, “A Black hole Farey tail,” arXiv:hep-th/0005003 [hep-th]

  12. [18]

    Superstrings on AdS(3) and symmetric products,

    R. Argurio, A. Giveon, and A. Shomer, “Superstrings on AdS(3) and symmetric products,” JHEP12(2000) 003,arXiv:hep-th/0009242

  13. [19]

    The Search for a holographic dual to AdS3 ×S 3 ×S 3 ×S 1,

    S. Gukov, E. Martinec, G. W. Moore, and A. Strominger, “The Search for a holographic dual to AdS3 ×S 3 ×S 3 ×S 1,”Adv. Theor. Math. Phys.9(2005) 435–525,arXiv:hep-th/0403090 [hep-th]. [,1519(2004)]

  14. [20]

    S. G. Avery,Using the D1D5 CFT to Understand Black Holes. PhD thesis, Ohio State U., 2010. arXiv:1012.0072 [hep-th]. http://inspirehep.net/record/878999/files/arXiv:1012.0072.pdf

  15. [21]

    Large N field theories, string theory and gravity,

    O. Aharony, S. S. Gubser, J. M. Maldacena, H. Ooguri, and Y. Oz, “Large N field theories, string theory and gravity,”Phys. Rept.323(2000) 183–386,arXiv:hep-th/9905111 [hep-th]

  16. [22]

    Microscopic formulation of black holes in string theory,

    J. R. David, G. Mandal, and S. R. Wadia, “Microscopic formulation of black holes in string theory,”Phys. Rept.369(2002) 549–686,arXiv:hep-th/0203048

  17. [23]

    Higher Spins & Strings,

    M. R. Gaberdiel and R. Gopakumar, “Higher Spins & Strings,”JHEP11(2014) 044, arXiv:1406.6103 [hep-th]

  18. [24]

    Stringy Symmetries and the Higher Spin Square,

    M. R. Gaberdiel and R. Gopakumar, “Stringy Symmetries and the Higher Spin Square,”J. Phys.A48(2015) no. 18, 185402,arXiv:1501.07236 [hep-th]

  19. [25]

    A holographic dual for string theory on AdS3 ×S 3 ×S 3 ×S 1,

    L. Eberhardt, M. R. Gaberdiel, and W. Li, “A holographic dual for string theory on AdS3 ×S 3 ×S 3 ×S 1,”JHEP08(2017) 111,arXiv:1707.02705 [hep-th]

  20. [26]

    StringyN= (2,2) holography for AdS 3,

    S. Datta, L. Eberhardt, and M. R. Gaberdiel, “StringyN= (2,2) holography for AdS 3,” arXiv:1709.06393 [hep-th]

  21. [27]

    Superstrings on AdS 3 atk= 1,

    G. Giribet, C. Hull, M. Kleban, M. Porrati, and E. Rabinovici, “Superstrings on AdS 3 atk= 1,” JHEP08(2018) 204,arXiv:1803.04420 [hep-th]

  22. [28]

    N= (3,3) holography on AdS 3 ×(S 3 ×S 3 ×S 1)/Z2,

    L. Eberhardt and I. G. Zadeh, “N= (3,3) holography on AdS 3 ×(S 3 ×S 3 ×S 1)/Z2,”JHEP07 (2018) 143,arXiv:1805.09832 [hep-th]

  23. [29]

    The Worldsheet Dual of the Symmetric Product CFT,

    L. Eberhardt, M. R. Gaberdiel, and R. Gopakumar, “The Worldsheet Dual of the Symmetric Product CFT,”JHEP04(2019) 103,arXiv:1812.01007 [hep-th]

  24. [30]

    String theory on AdS 3 and the symmetric orbifold of Liouville theory,

    L. Eberhardt and M. R. Gaberdiel, “String theory on AdS 3 and the symmetric orbifold of Liouville theory,”arXiv:1903.00421 [hep-th]. 58

  25. [31]

    Strings on AdS 3 ×S 3 ×S 3 ×S 1,

    L. Eberhardt and M. R. Gaberdiel, “Strings on AdS 3 ×S 3 ×S 3 ×S 1,”JHEP06(2019) 035, arXiv:1904.01585 [hep-th]

  26. [32]

    The Holographic Landscape of Symmetric Product Orbifolds,

    A. Belin, A. Castro, C. A. Keller, and B. M¨ uhlmann, “The Holographic Landscape of Symmetric Product Orbifolds,”JHEP01(2020) 111,arXiv:1910.05342 [hep-th]

  27. [33]

    Deriving the AdS 3/CFT2 correspondence,

    L. Eberhardt, M. R. Gaberdiel, and R. Gopakumar, “Deriving the AdS 3/CFT2 correspondence,” JHEP02(2020) 136,arXiv:1911.00378 [hep-th]

  28. [34]

    N= 2 Minimal Models: A Holographic Needle in a Symmetric Orbifold Haystack,

    A. Belin, N. Benjamin, A. Castro, S. M. Harrison, and C. A. Keller, “N= 2 Minimal Models: A Holographic Needle in a Symmetric Orbifold Haystack,”SciPost Phys.8(2020) no. 6, 084, arXiv:2002.07819 [hep-th]

  29. [35]

    AdS 3/CFT2 at higher genus,

    L. Eberhardt, “AdS 3/CFT2 at higher genus,”JHEP05(2020) 150,arXiv:2002.11729 [hep-th]

  30. [36]

    Partition functions of the tensionless string,

    L. Eberhardt, “Partition functions of the tensionless string,”JHEP03(2021) 176, arXiv:2008.07533 [hep-th]

  31. [37]

    From symmetric product CFTs to AdS3,

    M. R. Gaberdiel, R. Gopakumar, B. Knighton, and P. Maity, “From symmetric product CFTs to AdS3,”JHEP05(2021) 073,arXiv:2011.10038 [hep-th]

  32. [38]

    Asymptotically free AdS 3/CFT2,

    B. Balthazar, A. Giveon, D. Kutasov, and E. J. Martinec, “Asymptotically free AdS 3/CFT2,” JHEP01(2022) 008,arXiv:2109.00065 [hep-th]

  33. [39]

    A perturbative CFT dual for pure NS–NS AdS 3 strings,

    L. Eberhardt, “A perturbative CFT dual for pure NS–NS AdS 3 strings,”J. Phys. A55(2022) no. 6, 064001,arXiv:2110.07535 [hep-th]

  34. [40]

    Tensionless strings on AdS 3 orbifolds,

    M. R. Gaberdiel, B. Guo, and S. D. Mathur, “Tensionless strings on AdS 3 orbifolds,” arXiv:2312.01348 [hep-th]

  35. [41]

    Type II string theory on AdS3×S3×T4 and symmetric orbifolds,

    O. Aharony and E. Y. Urbach, “Type II string theory on AdS3×S3×T4 and symmetric orbifolds,”Phys. Rev. D110(2024) no. 4, 046028,arXiv:2406.14605 [hep-th]

  36. [42]

    Tensionless strings on AdS 3×S 3×S 3×S 1,

    M. R. Gaberdiel and V. Sriprachyakul, “Tensionless strings on AdS 3×S 3×S 3×S 1,”JHEP05 (2025) 003,arXiv:2411.16848 [hep-th]

  37. [43]

    Effective AdS 3/CFT2,

    S. Chakraborty, A. Giveon, and D. Kutasov, “Effective AdS 3/CFT2,”JHEP03(2025) 030, arXiv:2501.09119 [hep-th]

  38. [44]

    A localising AdS 3 sigma model,

    L. Eberhardt and M. R. Gaberdiel, “A localising AdS 3 sigma model,”arXiv:2505.09226 [hep-th]

  39. [45]

    The Conformal Field Theory of Orbifolds,

    L. J. Dixon, D. Friedan, E. J. Martinec, and S. H. Shenker, “The Conformal Field Theory of Orbifolds,”Nucl. Phys. B282(1987) 13–73

  40. [46]

    Correlation functions forM N /SN orbifolds,

    O. Lunin and S. D. Mathur, “Correlation functions forM N /SN orbifolds,”Commun. Math. Phys.219(2001) 399–442,arXiv:hep-th/0006196 [hep-th]

  41. [48]

    Virasoro amplitude from theS N R24 orbifold sigma model,

    G. E. Arutyunov and S. A. Frolov, “Virasoro amplitude from theS N R24 orbifold sigma model,” Theor. Math. Phys.114(1998) 43–66,arXiv:hep-th/9708129 [hep-th]

  42. [49]

    Four graviton scattering amplitude from S**N R**8 supersymmetric orbifold sigma model,

    G. E. Arutyunov and S. A. Frolov, “Four graviton scattering amplitude from S**N R**8 supersymmetric orbifold sigma model,”Nucl. Phys. B524(1998) 159–206, arXiv:hep-th/9712061. 59

  43. [50]

    Gravity from CFT on S**N(X): Symmetries and interactions,

    A. Jevicki, M. Mihailescu, and S. Ramgoolam, “Gravity from CFT on S**N(X): Symmetries and interactions,”Nucl. Phys. B577(2000) 47–72,arXiv:hep-th/9907144

  44. [51]

    Three point functions forM N /SN orbifolds withN= 4 supersymmetry,

    O. Lunin and S. D. Mathur, “Three point functions forM N /SN orbifolds withN= 4 supersymmetry,”Commun. Math. Phys.227(2002) 385–419,arXiv:hep-th/0103169 [hep-th]

  45. [52]

    Diagrams for Symmetric Product Orbifolds,

    A. Pakman, L. Rastelli, and S. S. Razamat, “Diagrams for Symmetric Product Orbifolds,”JHEP 10(2009) 034,arXiv:0905.3448 [hep-th]

  46. [53]

    Extremal Correlators and Hurwitz Numbers in Symmetric Product Orbifolds,

    A. Pakman, L. Rastelli, and S. S. Razamat, “Extremal Correlators and Hurwitz Numbers in Symmetric Product Orbifolds,”Phys. Rev. D80(2009) 086009,arXiv:0905.3451 [hep-th]

  47. [54]

    Twist-nontwist correlators inM N /SN orbifold CFTs,

    B. A. Burrington, A. W. Peet, and I. G. Zadeh, “Twist-nontwist correlators inM N /SN orbifold CFTs,”Phys. Rev. D87(2013) no. 10, 106008,arXiv:1211.6689 [hep-th]

  48. [55]

    The OPE of bare twist operators in bosonic SN orbifold CFTs at largeN,

    B. A. Burrington, I. T. Jardine, and A. W. Peet, “The OPE of bare twist operators in bosonic SN orbifold CFTs at largeN,”JHEP08(2018) 202,arXiv:1804.01562 [hep-th]

  49. [56]

    Comments on the S N orbifold CFT in the largeN-limit,

    K. Roumpedakis, “Comments on the S N orbifold CFT in the largeN-limit,”JHEP07(2018) 038,arXiv:1804.03207 [hep-th]

  50. [57]

    The largeNlimit of OPEs in symmetric orbifold CFTs withN= (4,4) supersymmetry,

    T. De Beer, B. A. Burrington, I. T. Jardine, and A. W. Peet, “The largeNlimit of OPEs in symmetric orbifold CFTs withN= (4,4) supersymmetry,”JHEP08(2019) 015, arXiv:1904.07816 [hep-th]

  51. [58]

    The Topological Symmetric Orbifold,

    S. Li and J. Troost, “The Topological Symmetric Orbifold,”JHEP10(2020) 201, arXiv:2006.09346 [hep-th]

  52. [59]

    Fractional conformal descendants and correlators in general 2D SN orbifold CFTs at large N,

    B. A. Burrington and A. W. Peet, “Fractional conformal descendants and correlators in general 2D SN orbifold CFTs at large N,”JHEP02(2023) 091,arXiv:2211.04633 [hep-th]

  53. [60]

    Larger twists and higher n-point functions with fractional conformal descendants in S N orbifold CFTs at large N,

    B. A. Burrington and A. W. Peet, “Larger twists and higher n-point functions with fractional conformal descendants in S N orbifold CFTs at large N,”JHEP02(2023) 229, arXiv:2212.03993 [hep-th]

  54. [61]

    Four-point functions with multi-cycle fields in symmetric orbifolds and the D1-D5 CFT,

    A. Alves Lima, G. M. Sotkov, and M. Stanishkov, “Four-point functions with multi-cycle fields in symmetric orbifolds and the D1-D5 CFT,”JHEP05(2022) 106,arXiv:2202.12424 [hep-th]

  55. [62]

    Bootstrapping multi-wound twist effects in symmetric orbifold CFTs,

    B. Guo and S. D. Hampton, “Bootstrapping multi-wound twist effects in symmetric orbifold CFTs,”arXiv:2307.14255 [hep-th]

  56. [63]

    Four-twist effects and monodromy in symmetric orbifold CFTs,

    B. Guo and S. D. Hampton, “Four-twist effects and monodromy in symmetric orbifold CFTs,” JHEP02(2025) 180,arXiv:2411.01774 [hep-th]

  57. [64]

    Four-twist effects on excitations in symmetric orbifold CFTs,

    B. Guo and S. D. Hampton, “Four-twist effects on excitations in symmetric orbifold CFTs,” arXiv:2503.21644 [hep-th]

  58. [65]

    Worldsheet correlators in AdS 3/CFT2,

    M. R. Gaberdiel and I. Kirsch, “Worldsheet correlators in AdS 3/CFT2,”JHEP04(2007) 050, arXiv:hep-th/0703001 [hep-th]

  59. [66]

    Exact chiral ring of AdS(3) / CFT(2),

    A. Dabholkar and A. Pakman, “Exact chiral ring of AdS(3) / CFT(2),”Adv. Theor. Math. Phys. 13(2009) no. 2, 409–462,arXiv:hep-th/0703022

  60. [67]

    Matching of correlators in AdS 3/CFT2,

    M. Taylor, “Matching of correlators in AdS 3/CFT2,”JHEP06(2008) 010,arXiv:0709.1838 [hep-th]. 60

  61. [68]

    Three-point functions in AdS 3/CFT2 holography,

    A. Dei, L. Eberhardt, and M. R. Gaberdiel, “Three-point functions in AdS 3/CFT2 holography,” JHEP12(2019) 012,arXiv:1907.13144 [hep-th]

  62. [69]

    Free field world-sheet correlators for AdS3,

    A. Dei, M. R. Gaberdiel, R. Gopakumar, and B. Knighton, “Free field world-sheet correlators for AdS3,”JHEP02(2021) 081,arXiv:2009.11306 [hep-th]

  63. [70]

    Stress-energy tensor correlators from the world-sheet,

    H. Bertle, A. Dei, and M. R. Gaberdiel, “Stress-energy tensor correlators from the world-sheet,” JHEP03(2021) 036,arXiv:2012.08486 [hep-th]

  64. [71]

    String correlators on AdS 3: three-point functions,

    A. Dei and L. Eberhardt, “String correlators on AdS 3: three-point functions,”JHEP08(2021) 025,arXiv:2105.12130 [hep-th]

  65. [72]

    String correlators on AdS 3: four-point functions,

    A. Dei and L. Eberhardt, “String correlators on AdS 3: four-point functions,”JHEP09(2021) 209,arXiv:2107.01481 [hep-th]

  66. [73]

    String correlators on AdS 3: Analytic structure and dual CFT,

    A. Dei and L. Eberhardt, “String correlators on AdS 3: Analytic structure and dual CFT,” SciPost Phys.13(2022) no. 3, 053,arXiv:2203.13264 [hep-th]

  67. [74]

    BPS correlators for AdS 3/CFT2,

    M. R. Gaberdiel and B. Nairz, “BPS correlators for AdS 3/CFT2,”JHEP09(2022) 244, arXiv:2207.03956 [hep-th]

  68. [75]

    Solving AdS 3 string theory at minimal tension: tree-level correlators,

    A. Dei, B. Knighton, and K. Naderi, “Solving AdS 3 string theory at minimal tension: tree-level correlators,”JHEP09(2024) 135,arXiv:2312.04622 [hep-th]

  69. [76]

    Spectral flow and localisation in AdS 3 string theory,

    B. Knighton, S. Seet, and V. Sriprachyakul, “Spectral flow and localisation in AdS 3 string theory,”JHEP05(2024) 113,arXiv:2312.08429 [hep-th]

  70. [77]

    Unravelling AdS 3/CFT2 near the boundary,

    B. Knighton and V. Sriprachyakul, “Unravelling AdS 3/CFT2 near the boundary,”JHEP01 (2025) 042,arXiv:2404.07296 [hep-th]

  71. [78]

    Correlators of long strings on AdS 3×S3×T4,

    Z.-f. Yu and C. Peng, “Correlators of long strings on AdS 3×S3×T4,”JHEP01(2025) 017, arXiv:2408.16712 [hep-th]

  72. [79]

    On the CFT dual of superstring on AdS 3,

    Z.-f. Yu, “On the CFT dual of superstring on AdS 3,”arXiv:2504.20227 [hep-th]

  73. [80]

    Correlation functions on the critical lines of the Baxter and Ashkin-Teller models,

    L. P. Kadanoff and A. C. Brown, “Correlation functions on the critical lines of the Baxter and Ashkin-Teller models,”Annals Phys.121(1979) 318–342

  74. [81]

    Multicritical behavior at the kosterlitz-thouless critical point,

    L. P. Kadanoff, “Multicritical behavior at the kosterlitz-thouless critical point,”Annals of Physics120(1979) no. 1, 39–71

  75. [82]

    Continuously Varying Exponents and the Value of the Central Charge,

    J. L. Cardy, “Continuously Varying Exponents and the Value of the Central Charge,”J. Phys. A20(1987) L891–L896

  76. [83]

    Geometry on the Space of Conformal Field Theories and Contact Terms,

    D. Kutasov, “Geometry on the Space of Conformal Field Theories and Contact Terms,”Phys. Lett.B220(1989) 153–158

  77. [84]

    On moduli spaces of conformal field theories withc >= 1,

    R. Dijkgraaf, E. P. Verlinde, and H. L. Verlinde, “On moduli spaces of conformal field theories withc >= 1,” inIn *Copenhagen 1987, proceedings, perspectives in string theory* 117-137. 1987

  78. [85]

    Conformal manifolds: ODEs from OPEs,

    C. Behan, “Conformal manifolds: ODEs from OPEs,”JHEP03(2018) 127,arXiv:1709.03967 [hep-th]

  79. [86]

    Conformal perturbation theory for n-point functions: structure constant deformation,

    B. A. Burrington and I. G. Zadeh, “Conformal perturbation theory for n-point functions: structure constant deformation,”JHEP2024(2024) 078,arXiv:2312.13337 [hep-th]

  80. [87]

    String Universality for Permutation Orbifolds,

    A. Belin, C. A. Keller, and A. Maloney, “String Universality for Permutation Orbifolds,”Phys. Rev.D91(2015) no. 10, 106005,arXiv:1412.7159 [hep-th]. 61

  81. [88]

    Permutation Orbifolds in the large N Limit,

    A. Belin, C. A. Keller, and A. Maloney, “Permutation Orbifolds in the large N Limit,” arXiv:1509.01256 [hep-th]

  82. [89]

    Analyzing the squeezed state generated by a twist deformation,

    B. A. Burrington, S. D. Mathur, A. W. Peet, and I. G. Zadeh, “Analyzing the squeezed state generated by a twist deformation,”Phys. Rev. D91(2015) no. 12, 124072,arXiv:1410.5790 [hep-th]

  83. [90]

    Bosonization, cocycles, and the D1-D5 CFT on the covering surface,

    B. A. Burrington, A. W. Peet, and I. G. Zadeh, “Bosonization, cocycles, and the D1-D5 CFT on the covering surface,”Phys. Rev. D93(2016) no. 2, 026004,arXiv:1509.00022 [hep-th]

  84. [91]

    Tensionless string spectra on AdS 3,

    M. R. Gaberdiel and R. Gopakumar, “Tensionless string spectra on AdS 3,”JHEP05(2018) 085, arXiv:1803.04423 [hep-th]

  85. [93]

    Ronveaux,Heun ’s Differential Equations

    A. Ronveaux,Heun ’s Differential Equations. Oxford University Press, Oxford Oxfordshire, 1995

  86. [94]

    On a polynomial transformation of hypergeometric equations, Heun’s differential equation and exceptional Jacobi polynomials,

    M. N. Hounkonnou and A. Ronveaux, “On a polynomial transformation of hypergeometric equations, Heun’s differential equation and exceptional Jacobi polynomials,”arXiv:1306.4889 [math-ph]

  87. [95]

    Heun’s equation, generalized hypergeometric function and exceptional Jacobi polynomial,

    K. Takemura, “Heun’s equation, generalized hypergeometric function and exceptional Jacobi polynomial,”J. Phys. A45(2012) no. 8, 085211, 14

  88. [96]

    Szego,Orthogonal Polynomials

    G. Szego,Orthogonal Polynomials. Colloquium Publications. American Mathematical Society, 1939

  89. [97]

    The irreducibility of certain pure-cycle hurwitz spaces,

    F. Liu and B. Osserman, “The irreducibility of certain pure-cycle hurwitz spaces,”American journal of mathematics130(2008) 1687,arXiv:0609118 [math]

  90. [98]

    F. W. J. Olver, , D. W. Lozier, R. F. Boisvert, and C. W. Clark,The NIST Handbook of Mathematical Functions (Online Version here). Cambridge Univ. Press, 2010

  91. [99]

    I. S. Gradshteyn and I. M. Ryzhik,Table of Integrals, Series, and Products. 1943. 62

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