REVIEW 2 minor 25 references
Ramanujan's and Lim's Identities and Harmonic Maass--Jacobi Forms
T0 review · 0 major / 2 minor · reviewed 2026-06-27 · grok-4.3
Pith's one-line read Jacobi analogues of Eichler integrals complete explicitly to singular harmonic Maass-Jacobi forms in negative weight.
desk verdict This paper builds explicit Jacobi analogues of Eichler integrals, completes them to singular harmonic Maass-Jacobi forms in negative weight, and derives inversion formulas via direct verification of the transformation laws. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
Completed Jacobi analogues of classical Eichler integrals of Eisenstein series, which serve as singular harmonic Maass--Jacobi forms.
What would settle it
An explicit calculation for a fixed negative weight and a generator of the Jacobi modular group in which the completed object fails to satisfy the required transformation law would disprove the claim that the completions are singular harmonic Maass--Jacobi forms.
Extended reading notes
Core claim
We construct explicit completions of the Jacobi analogues of the classical Eichler integrals of Eisenstein series in negative weight and prove that they are singular harmonic Maass--Jacobi forms. Their non-holomorphic parts are described in terms of Eichler integrals. Ramanujan-type inversion formulas are established, and their behavior under the Maass raising and lowering operators and at torsion points is studied.
Load-bearing premise
The Jacobi analogues of the classical Eichler integrals admit explicit completions whose non-holomorphic parts can be described in terms of Eichler integrals while preserving the required transformation properties under the Jacobi modular group.
Editorial extensions
If this is right
- The completed objects transform as singular harmonic Maass--Jacobi forms under the Jacobi modular group.
- Their non-holomorphic parts are given explicitly by Eichler integrals.
- Ramanujan-type inversion formulas hold for the completed forms.
- The forms admit explicit descriptions of their images under the Maass raising and lowering operators.
- Their values at torsion points satisfy the expected arithmetic relations.
Reading between the lines
- The modular framework may allow extraction of new linear relations among odd zeta values by evaluating the completed forms at suitable points.
- The same completion procedure could be applied to Eichler integrals attached to other Eisenstein series or to forms of different levels.
- Direct numerical verification of the inversion formulas at small torsion points would provide an independent check on the explicit completions.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper extends Ramanujan's identities for odd zeta values, as previously studied by Lim, by introducing Jacobi analogues of the classical Eichler integrals of Eisenstein series. In negative weight, it constructs explicit completions of these objects and proves that they are singular harmonic Maass--Jacobi forms. It further describes their non-holomorphic parts in terms of Eichler integrals, establishes Ramanujan-type inversion formulas, and investigates their behavior under the Maass raising and lowering operators as well as at torsion points.
Significance. This manuscript provides an explicit modular completion for the Jacobi analogues of Eichler integrals in negative weight, embedding them into the framework of harmonic Maass-Jacobi forms through direct verification of the transformation laws under the Jacobi modular group. The use of ordinary Eichler integrals to describe the non-holomorphic parts is consistent with the classical case and represents a strength of the work. The additional study of the Maass operators and torsion points adds depth to the analysis. If the calculations are correct, this contributes to the understanding of these identities in a modular context.
minor comments (2)
- [Abstract] The abstract mentions constructions in negative weight but does not specify the precise range of weights; adding this would improve clarity for readers.
- Notation for the Jacobi slash operators and the precise definition of the Jacobi modular group action should be explicitly recalled or referenced early in the introduction to aid readers unfamiliar with the setting.
Simulated Author's Rebuttal
We thank the referee for the positive summary, significance assessment, and recommendation of minor revision. No major comments were listed in the report.
Circularity Check
No significant circularity; derivation self-contained
full rationale
The paper defines Jacobi analogues of Eichler integrals explicitly, constructs their non-holomorphic completions in negative weight by direct formulas, and verifies the harmonic Maass-Jacobi transformation properties under the Jacobi group via explicit (if lengthy) calculations of slash operators and theta factors. Non-holomorphic parts are expressed using ordinary Eichler integrals of Eisenstein series, which follows the classical pattern once Jacobi-specific operators are inserted; no step reduces a claimed result to a fitted parameter, self-citation chain, or definitional renaming. The constructions rest on external modular-form theory and direct verification rather than any of the enumerated circular patterns.
Assumptions & free parameters
Cite this review
Pith. "Pith review of Ramanujan's and Lim's Identities and Harmonic Maass--Jacobi Forms." pith.science (2026). https://pith.science/paper/M4Z7N3MN
@misc{pith2026260613173,
author = {Pith},
title = {Pith review of: Ramanujan's and Lim's Identities and Harmonic Maass--Jacobi Forms},
year = {2026},
howpublished = {\url{https://pith.science/paper/M4Z7N3MN}},
note = {Machine review of arXiv:2606.13173}
}
read the original abstract
We study an extension of Ramanujan's identities for odd zeta values by Lim and introduce Jacobi analogues of classical Eichler integrals of Eisenstein series. In negative weight we construct explicit completions and embed these objects into a modular framework by showing that they are (singular) harmonic Maass--Jacobi forms. We further describe their non-holomorphic parts in terms of Eichler integrals, establish Ramanujan-type inversion formulas, and study their behavior under the Maass raising and lowering operators and at torsion points.
Reference graph
Works this paper leans on
-
[1]
Andrews and B
G. Andrews and B. Berndt,Ramanujan’s lost notebook. Part IV, Springer, New York, 2013
2013
-
[2]
M. Berg, K. Bringmann, and T. Gannon,Massive deformations of Maass forms and Jacobi forms, Commun. Number Theory Phys.15(2021), 575–603
2021
-
[3]
Berndt and A
B. Berndt and A. Straub,Ramanujan’s formula forζ(2m+ 1), inExploring the Riemann zeta function, eds. H. Montgomery, A. Nikeghbali, and M. Rassias, pp. 13–34, Springer, Cham, 2017
2017
-
[4]
Bringmann, A
K. Bringmann, A. Folsom, K. Ono, and L. Rolen,Harmonic Maass forms and mock modular forms: Theory and applications, Amer. Math. Soc. Colloq. Publ., Vol. 64, American Mathematical Society, Providence, RI, 2017
2017
-
[5]
Bringmann, M
K. Bringmann, M. Krauel, and M. Tuite,Zhu reduction for Jacobin-point functions and applications, Trans. Amer. Math. Soc.373(2020), no. 5, 3261–3293
2020
-
[6]
Bringmann, K
K. Bringmann, K. Ono, and I. Wagner,Eichler integrals of Eisenstein series asq-brackets of weightedt-hook functions on partitions, Ramanujan J.61(2023), 279–293
2023
-
[7]
Bringmann and O
K. Bringmann and O. Richter,Zagier-type dualities and lifting maps for harmonic Maass–Jacobi forms, Adv. Math.225(2010), 2298–2315
2010
-
[8]
F. Brunault and W. Zudilin,Modular regulators and multiple Eisenstein values, arXiv:2303.15554
Show all 25 references
-
[9]
Cohen and F
H. Cohen and F. Str¨ omberg,Modular forms: A classical approach, Graduate Studies in Mathematics, Vol. 179, American Mathematical Society, Providence, RI, 2017
2017
-
[10]
D’Hoker, M
E. D’Hoker, M. Green, ¨O. G¨ urdo˘ gan, and P. Vanhove,Modular graph functions, Commun. Number Theory Phys. 11(2017), no. 1, 165–218
2017
-
[11]
D’Hoker, M
E. D’Hoker, M. Green, and B. Pioline,Asymptotics of theD 8R4 genus-two string invariant, Commun. Number Theory Phys.13(2019), no. 2, 351–462
2019
-
[12]
D’Hoker, A
E. D’Hoker, A. Kleinschmidt, and O. Schlotterer,Elliptic modular graph forms I: Identities and generating series, J. High Energy Phys.2021(2021), 3, 151
2021
-
[13]
Diamond and J
F. Diamond and J. Shurman,A first course in modular forms, Graduate Texts in Mathematics, Vol. 228, Springer, New York, 2005
2005
-
[14]
Eichler and D
M. Eichler and D. Zagier,The theory of Jacobi forms, Progr. Math., Vol. 55, Birkh¨ auser, Boston, 1985
1985
-
[15]
Hidding, O
M. Hidding, O. Schlotterer, and B. Verbeek,Elliptic modular graph forms II: Iterated integrals, arXiv.2208.11116
-
[16]
Lim,A class of infinite series from generalized Eisenstein series, Honam Math
S. Lim,A class of infinite series from generalized Eisenstein series, Honam Math. J.34(2012), no. 3, 391–402
2012
-
[17]
Libgober,Elliptic genera, real algebraic varieties and quasi-Jacobi forms, inTopology of Stratified Spaces, Math
A. Libgober,Elliptic genera, real algebraic varieties and quasi-Jacobi forms, inTopology of Stratified Spaces, Math. Sci. Res. Inst. Publ.,58, Cambridge Univ. Press, Cambridge, 2011, pp. 95–120
2011
-
[18]
Olver, D
F. Olver, D. Lozier, R. Boisvert, and C. Clark,NIST handbook of mathematical functions, Cambridge University Press, Cambridge, 2010
2010
-
[19]
Pasles and W
P. Pasles and W. Pribitkin,A generalization of the Lipschitz summation formula and some applications, Proc. Amer. Math. Soc.129(2001), no. 11, 3177–3184
2001
-
[20]
Ramanujan,The lost notebook and other unpublished papers, Narosa, New Delhi, 1988
S. Ramanujan,The lost notebook and other unpublished papers, Narosa, New Delhi, 1988
1988
-
[21]
Schlotterer, Y
O. Schlotterer, Y. Sohnle, and Y.-X. Tao,Elliptic modular graph forms, equivariant iterated integrals and single- valued elliptic polylogarithms, arXiv:2511.15883
-
[22]
Siegel,Lectures on advanced analytic number theory, Tata Institute of Fundamental Research, Bombay, 1961
C. Siegel,Lectures on advanced analytic number theory, Tata Institute of Fundamental Research, Bombay, 1961
1961
-
[23]
Zagier,The Bloch–Wigner–Ramakrishnan polylogarithm function, Math
D. Zagier,The Bloch–Wigner–Ramakrishnan polylogarithm function, Math. Ann.286(1990), 613–624
1990
-
[24]
Zhu,Modular invariance of characters of vertex operator algebras, J
Y. Zhu,Modular invariance of characters of vertex operator algebras, J. Amer. Math. Soc.9(1996), no. 1, 237–302
1996
-
[25]
Zwegers,Mock theta functions, Ph.D
S. Zwegers,Mock theta functions, Ph.D. thesis, Universiteit Utrecht, 2002. University of Cologne, Department of Mathematics and Computer Science, Weyertal 86-90, 50931 Cologne, Germany Email address:kbringma@math.uni-koeln.de Email address:bpandey@uni-koeln.de, badrivishal9451...
2002
Reviewed June 27, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.