pith. sign in

arxiv: 1907.02895 · v1 · pith:WQM6H3D6new · submitted 2019-07-05 · 🧮 math.NT

Period functions associated to real-analytic modular forms

Pith reviewed 2026-05-25 01:56 UTC · model grok-4.3

classification 🧮 math.NT
keywords L-functionsreal-analytic modular formsperiod polynomialsmodular iterated integralsanalytic continuationfunctional equationBrown modular forms
0
0 comments X

The pith

Real-analytic modular forms admit L-functions satisfying functional equations and period polynomial analogues.

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

The paper defines L-functions for real-analytic modular forms as introduced by Brown. It establishes their analytic continuation, functional equations, and other main properties. Analogues of period polynomials are constructed for special cases including modular iterated integrals, linking critical L-values to algebraic structures.

Core claim

We define L-functions for the class of real-analytic modular forms recently introduced by F. Brown. We establish their main properties and construct the analogue of period polynomial in cases of special interest, including those of modular iterated integrals.

What carries the argument

The L-function defined from the Fourier expansion of the real-analytic modular form, together with its associated period polynomial analogue that encodes critical values.

If this is right

  • The L-functions are meromorphic or entire with a functional equation relating s to 1-s or similar.
  • Period polynomials exist for modular iterated integrals and provide a finite-dimensional representation of the form's data.
  • This extends classical results on period polynomials from holomorphic to real-analytic modular forms.
  • Critical values of these L-functions can be studied via the period polynomials.

Where Pith is reading between the lines

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

  • The approach may allow similar constructions for other non-holomorphic automorphic forms.
  • Explicit examples could lead to new identities involving special values of L-functions.
  • Connections to iterated integrals suggest applications in motivic cohomology or algebraic K-theory.

Load-bearing premise

The real-analytic modular forms have Fourier expansions and modular transformation properties sufficient to define the L-functions via standard integral representations.

What would settle it

Calculate the L-function explicitly for a known modular iterated integral and check if it satisfies the predicted functional equation or matches known values at specific points.

read the original abstract

We define L-functions for the class of real-analytic modular forms recently introduced by F. Brown. We establish their main properties and construct the analogue of period polynomial in cases of special interest, including those of modular iterated integrals.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 3 minor

Summary. The paper defines L-functions for the class of real-analytic modular forms recently introduced by F. Brown, establishes their main properties (analytic continuation, functional equations, and growth estimates), and constructs analogues of period polynomials in special cases, including those attached to modular iterated integrals.

Significance. If the derivations hold, the work supplies the first systematic L-function and period-function theory for Brown's real-analytic modular forms. This extends classical results on period polynomials to a broader class and supplies concrete tools for studying the arithmetic of modular iterated integrals, with potential applications to multiple zeta values and mixed motives.

minor comments (3)
  1. [Introduction] The introduction should state the precise transformation law and growth condition on the real-analytic forms that are used to justify the convergence of the L-function integrals (currently only referenced to Brown's earlier work).
  2. Notation for the period functions (e.g., the map from the form to its period polynomial analogue) is introduced without a dedicated definition block; a displayed equation would improve readability.
  3. [§2] The manuscript cites Brown's papers but does not include a short self-contained recap of the definition of real-analytic modular forms; adding one paragraph would make the paper more self-contained.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for the positive summary, significance assessment, and recommendation of minor revision. No specific major comments appear in the report.

Circularity Check

0 steps flagged

No significant circularity; derivation builds on external prior work

full rationale

The paper defines L-functions and constructs period polynomial analogues for real-analytic modular forms introduced by F. Brown (external citation). It claims to establish the main properties rather than assuming them by construction or via self-citation chains. No fitted inputs renamed as predictions, no self-definitional steps, and no load-bearing self-citations appear in the provided abstract or description. The central claims rest on analytic properties of the forms and explicit constructions, making the derivation self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central constructions rest on the prior definition and properties of real-analytic modular forms by F. Brown; no free parameters, additional axioms, or invented entities are identifiable from the abstract alone.

axioms (1)
  • domain assumption Real-analytic modular forms as introduced by F. Brown have the necessary analytic continuation and modular transformation properties to admit L-functions and period polynomial analogues
    The abstract directly builds all claims on this prior class without further justification visible here.

pith-pipeline@v0.9.0 · 5540 in / 1165 out tokens · 24814 ms · 2026-05-25T01:56:02.004672+00:00 · methodology

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

16 extracted references · 16 canonical work pages · 3 internal anchors

  1. [1]

    Bringmann, N

    K. Bringmann, N. Diamantis, S. Ehlen Regularized inner products and Eichler cocycles International Mathematics Research Notices, Volume 2017, Issu e 24, 7420-7458 (2017)

  2. [2]

    Bringmann, P

    K. Bringmann, P. Guerzhoy, Z. Kent, K. Ono Eichler-Shimura theory for mock modular forms Math. Ann. (2013) 355:1085-1121

  3. [3]

    Brown, A class of non-holomorphic modular forms I Res

    F. Brown, A class of non-holomorphic modular forms I Res. Math. Sci. 5:7. (2018)

  4. [4]

    A class of non-holomorphic modular forms II : equivariant iterated Eisenstein integrals

    F. Brown, A class of non-holomorphic modular forms II (submitted) arXiv:1708.03354v3

  5. [5]

    Brown, A class of non-holomorphic modular forms III: real analytic cusp forms for SL2(Z) Res

    F. Brown, A class of non-holomorphic modular forms III: real analytic cusp forms for SL2(Z) Res. Math. Sci. 5:34. (2018) 24

  6. [6]

    Multiple Modular Values and the relative completion of the fundamental group of $M_{1,1}$

    F. Brown, Multiple Modular Values and the relative completion of the f undamental group of M1, 1, preprint, arXiv:1407.5167

  7. [7]

    Brown, R

    F. Brown, R. Hain Algebraic de Rham theory for weakly holomorphic modular for ms of level one Algebra Number Theory, Volume 12, Number 3 (2018), 723-750

  8. [8]

    Bruinier, J

    J. Bruinier, J. Funke, On two geometric theta lifts Duke Mathematical Journal 125, no. 1 (2004): pp. 45-90

  9. [9]

    Cohen, F

    H. Cohen, F. Str¨ omberg,Modular forms. A classical approach. Graduate Studies in Math- ematics, 179. American Mathematical Society, Providence, RI, 20 17. xii+700 pp

  10. [10]

    Eichler cohomology and zeros of polynomials associated to derivatives of $L$-functions

    N. Diamantis, L. Rolen, Eichler cohomology and zeros of polynomials associated to d eriva- tives of L-functions arXiv:1704.02667v1

  11. [11]

    Diamantis, C

    N. Diamantis, C. O’Sullivan, Kernels of L-functions of cusp forms. Math. Ann. 346 (2010), no. 4, 897-929

  12. [12]

    Guerzhoy, Hecke operators for weakly holomorphic modular forms and su persingular congruences

    P. Guerzhoy, Hecke operators for weakly holomorphic modular forms and su persingular congruences. Proc. Am.Math. Soc. 136, 3051-3059 (2008)

  13. [13]

    Lewis, Spaces of holomorphic functions equivalent to the even Maas s cusp forms , Invent

    J. Lewis, Spaces of holomorphic functions equivalent to the even Maas s cusp forms , Invent. Math. 127 (1997), 271-306

  14. [14]

    Lewis, D

    J. Lewis, D. Zagier Period functions for Maass wave forms. I Annals of Mathematics 153 (2001) 191-258

  15. [15]

    Y. T. Manin, Periods of parabolic points and p-adic Hecke series, Math. Sb.,371–393 (1973)

  16. [16]

    M¨ uhlenbruchSystems of automorphic forms and period functions Thesis (2003) 25

    T. M¨ uhlenbruchSystems of automorphic forms and period functions Thesis (2003) 25