REVIEW
Zero-free half-planes for Hecke $L$-functions over number fields and Quasi-Riemann Hypothesis
Number Theory · Submitted 19 Oct 2026
Pith's verdict: A serious conditional result: clean scalar mechanics and a real new boundary, but the headline theorem currently leans on an unpublished preprint and on sections I could not see.
T0 · AI review
Why Pith says this
Highlight any text to comment on it.
Referee report
The paper
The paper claims
For every number field $K$ and every finite-order Hecke character $\chi$, the Hecke $L$-function $L_K(s,\chi)$ is zero-free in $\operatorname{Re}(s) > B_{\flat} = 0.874886647039964\ldots$, with the principal character's pole at $s=1$…
The reading
What carries the argument
The engine is the exceptional $\theta$ representation of Kazhdan–Patterson — the automorphic representation attached to the rank-two, degree-three metaplectic cover, normalized so that its local Whittaker table has $W_p(a(\varpi^e u)) = \chi_p(u)^{2e}W_p(a(\varpi^e))$, nonzero exactly for $e \equiv 0, 1 \pmod 3$ with values $q_p^{-k}$ and $q_p^{-k-1/2}\gamma_2(p)$, and obeying the recurrence $J_{e+3} = q^{-1}J_e$. Over a cyclotomic field $F \supset \mu_{12}$ it replaces the cubic $\theta$ function of the $\mathbb{Q}(\sqrt{-3})$ argument; its radial functional equation (Proposition 5.2) turns reflected norm-sheet sums into compactly supported smooth tests and thereby carries the inverse moments (Theorems 10.4 and 11.2) and the unweighted product moment for $13/18 \leq \kappa \leq 1$ (Theorem 12.14). The scalar comparison system is the second engine: the endpoint exponents $E_{\mathrm{pt}}$ (pointwise numerator) and $E_{\mathrm{av}}$ (averaged numerator), the tangent-parameter family of Lemma 14.10, and the fixed-point identity $F_{\flat}(\kappa_{\flat}) = (1+\kappa_{\flat})/2 = B_{\flat}$ with $\kappa_{\flat} = 2B_{\flat} - 1$, which becomes the quartic defining $B_{\flat}$. Class-field descent, using only $\mu_{12} \subseteq F$ and general-field sieve and reciprocity inputs, then lifts the cyclotomic statement to every number field.
Extended reading notes
Core claim
The paper's central claim, the Main Theorem (Theorem 17.1; Theorem 3.2 for cyclotomic base fields and their class-field descendants), states that for every number field $K$ and every finite-order Hecke character $\chi$ of $K$, $L_K(s,\chi) \neq 0$ for $\operatorname{Re}(s) > B_{\flat}$, where $B_{\flat} = 0.874886647039964\ldots$ is the root near $0.8749$ of $133488B^4 - 376596B^3 + 384534B^2 - 167541B + 26231 = 0$; the pole of the principal character at $s=1$ is permitted, and in particular $\zeta_K(s) \neq 0$ for $\operatorname{Re}(s) > B_{\flat}$, $s \neq 1$, with no assertion on the boundary line itself. The paper further claims that $B_{\flat}$ is the exact infimum of the refined comparison system built from the moment parameter $\kappa$ and the averaged-numerator estimate: every finite chain of admissible refined steps starting from a bound at least $B_{\flat}$ produces only boundaries at least $B_{\flat}$, yet chains starting from $7/8$ approach $B_{\flat}$ from above within any $\varepsilon$, so the limiting contradiction argument attains an endpoint no finite chain can reach. The larger boundary $B_{\infty} = B_{\mathrm{new}} = 0.874957019420098946\ldots$ is separately shown to be the infimum of the pointwise-numerator system, and the improvement to $B_{\flat}$ is attributed concretely to replacing the pointwise reflected-numerator bound by an amplified first moment. Because the analytic argument is asserted to use only the containment $\mu_{12} \subseteq F$ plus standard facts valid for every number field, the cyclotomic theorem is run over $F = K(\zeta_{12})$ and descended to arbitrary $K$ by class-field factorization; the paper stresses that the $\theta$ constructions and local calculations are imported from the preprint [Ope26b] but not that preprint's zero-free conclusion, and it states in Remark 3.1 that the accompanying machine-checked formalization covers only scalar and selected arithmetic implications, not the complete analytic argument of Part II.
Load-bearing premise
The engine of the argument — the exceptional $\theta$ representation over a cyclotomic field containing the $12$th roots of unity, with its local Whittaker table, radial functional equation, and small-norm bounds — is imported from the unpublished preprint [Ope26b], and the abstract acknowledges that the moments rest on it; if that construction or its normalizations are wrong, the boundary $B_{\flat}$ has no support, and likewise if the Section 18 claim that only $\mu_{12} \subseteq F$ and standard facts are used should fail for some number field, the descent to every $K$ collapses.
Editorial extensions
If this is right
- A uniform zero-free half-plane at $B_{\flat} = 0.874886647039964\ldots$ holds for $\zeta_K$ and for every finite-order Hecke $L$-function over every number field, uniformly in the field, the character, and the conductor, with the principal pole at $s=1$ the only permitted singularity.
- The boundary improves the two benchmarks cited: the uniform $31/32$ region for arbitrary number fields from [CT26] and the recent $B_{\mathrm{new}} \approx 0.874957$ for $\mathbb{Q}(\sqrt{-3})$; over $\mathbb{Q}(\sqrt{-3})$ the boundary $8748867/10^7$ of the averaged-numerator method is recovered as a stage in the rational chain of Appendix B.
- Optimality within the method: $B_{\flat}$ is the exact infimum of the refined comparison system — every finite chain of admissible refined steps starting above $B_{\flat}$ yields only boundaries $\geq B_{\flat}$, while chains from $7/8$ come within any $\varepsilon$ of $B_{\flat}$ from above — so the bound is a sharp output of the stated system, reached only by the limiting contradiction argument.
- Arithmetic scope: the cyclotomic theorem descends to every pair $(K,\eta)$ whose cyclic class field becomes abelian over a cyclotomic field containing $\mu_{12}$ (in particular every finite-order character over every abelian number field), and the $\mu_{12}$-only argument extends the boundary to every number field.
Reading between the lines
- A consequence the paper leaves implicit: because parameter variation inside the refined comparison system cannot go below $B_{\flat}$, any future reduction of the boundary must come from one of the inputs the paper itself flags as capable of changing the obstruction — a stronger mean-value estimate, a joint moment for the detecting polynomials, larger admissible prime lengths, or better functional
- The descent template is portable: the same scheme — prove a moment estimate over $K(\zeta_{12})$ using only the root-of-unity condition, then push down by class-field factorization — should apply to neighbouring families, such as norm-twisted or higher-degree automorphic $L$-functions, whenever an exceptional theta input exists over a cyclotomic field; Part III's analysis shows how little of the a
- An exact-arithmetic foothold the paper supplies: the rational chain of Appendix B ending at $B_{\sharp} = 874886647041/10^{12}$, within $1.04 \times 10^{-12}$ of $B_{\flat}$, is independently checkable and would expose any slip in the quartic or its root even without the analytic argument.
Original abstract
In [Liu26a], varying the length and moment parameters in the cubic-theta argument of [Ope26a] gave the zero-free half-plane $Re(s)>B_{\mathrm{new}}=0.874957019420098946\ldots$ for finite-order Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and for Dirichlet $L$-functions, and its optimality in the specified exponent comparison system. In this paper, we extend the argument to finite-order Hecke $L$-functions over cyclotomic fields containing $\mu_{12}$ and, by class-field descent, to every pair $(K,\eta)$ whose cyclic class field has metabelian normal closure over $\mathbb Q$, including every finite-order character over every abelian number field. Then, adapting the averaged numerator estimate developed by Xu and Sang [XS26] for Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and combining it with a limiting contradiction argument, we obtain the boundary $B_\flat=0.874886647039964\ldots$, the root near $0.8749$ of $133488B^4-376596B^3+384534B^2-167541B+26231$; it is the exact infimum of the refined comparison system, unattained by finite chains starting above it. Since the analytic argument uses only $\mu_{12}\subset F$, we run it over $F=K(\zeta_{12})$ for an arbitrary number field $K$ and descend: every finite-order Hecke $L$-function over every number field is zero-free for $Re(s)>B_\flat$, giving a uniform Quasi-Riemann Hypothesis over number fields. The analytic argument uses the exceptional-theta constructions and local calculations of the preprint [Ope26b].
The compiled record
The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.
The abstract, sentence by sentence
In [Liu26a], varying the length and moment parameters in the cubic-theta argument of [Ope26a] gave the zero-free half-plane $Re(s)>B_{\mathrm{new}}=0.874957019420098946\ldots$ for finite-order Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and for Dirichlet $L$-functions, and its optimality in the specified exponent comparison system. In this paper, we extend the argument to finite-order Hecke $L$-functions over cyclotomic fields containing $\mu_{12}$ and, by class-field descent, to every pair $(K,\eta)$ whose cyclic class field has metabelian normal closure over $\mathbb Q$, including every finite-order character over every abelian number field. Then, adapting the averaged numerator estimate developed by Xu and Sang [XS26] for Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and combining it with a limiting contradiction argument, we obtain the boundary $B_\flat=0.874886647039964\ldots$, the root near $0.8749$ of $133488B^4-376596B^3+384534B^2-167541B+26231$; it is the exact infimum of the refined comparison system, unattained by finite chains starting above it. Since the analytic argument uses only $\mu_{12}\subset F$, we run it over $F=K(\zeta_{12})$ for an arbitrary number field $K$ and descend: every finite-order Hecke $L$-function over every number field is zero-free for $Re(s)>B_\flat$. The analytic argument uses the exceptional-theta constructions and local calculations of the preprint [Ope26b].
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | In [Liu26a], varying the length and moment parameters in the cubic-theta argument of [Ope26a] gave the zero-free half-plane $Re(s)>B_{\mathrm{new}}=0.874957019420098946\ldots$ for finite-order Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and for Dirichlet $L$-functions, and its optimality in the specified exponent comparison system. | background 0.99 | 0.16 | 0.05 | asserted 1.00 |
| s1 | In this paper, we extend the argument to finite-order Hecke $L$-functions over cyclotomic fields containing $\mu_{12}$ and, by class-field descent, to every pair $(K,\eta)$ whose cyclic class field has metabelian normal closure over $\mathbb Q$, including every finite-order character over every abelian number field. | contribution 0.98 | 0.84 | 0.17 | asserted 1.00 |
| s2 | Then, adapting the averaged numerator estimate developed by Xu and Sang [XS26] for Hecke $L$-functions over $\mathbb Q(\sqrt{-3})$ and combining it with a limiting contradiction argument, we obtain the boundary $B_\flat=0.874886647039964\ldots$, the root near $0.8749$ of $133488B^4-376596B^3+384534B^2-167541B+26231$; it is the exact infimum of the refined comparison system, unattained by finite chains starting above it. | result 0.95 | 0.93 | 0.30 | asserted 1.00 |
| s3 | Since the analytic argument uses only $\mu_{12}\subset F$, we run it over $F=K(\zeta_{12})$ for an arbitrary number field $K$ and descend: every finite-order Hecke $L$-function over every number field is zero-free for $Re(s)>B_\flat$. | result 0.52 | 0.85 | 0.81 | asserted 1.00 |
| s4 | The analytic argument uses the exceptional-theta constructions and local calculations of the preprint [Ope26b]. | method 0.83 | 0.15 | 0.02 | asserted 0.99 |
What was examined, and what was not
- arXiv listing abstract v1
- full text
- figures and tables
- references and citing sentences
- relations to other papers
- P abstract
- S sections
- T body sentences
- C citations
- R cross-paper relations
References
Discussion
Disagree with the review, or know something it missed? Leave a comment, highlight any passage above to comment on it, or challenge this review formally.