REVIEW 5 minor 26 references
On the additive structure of algebraic valuations of polynomial semirings II
T0 review · 0 major / 5 minor · reviewed 2026-07-12 · grok-4.5
Pith's one-line read Additive monoids from algebraic numbers are antimatter exactly when they are finite products of valuation monoids, characterized by Perron numbers.
desk verdict Clean, self-contained characterizations that finish the atomic/antimatter picture for M_α via Perron numbers and recurrences; specialized but solid. 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
The reduction to simple polynomials (via the simplified monoid of Proposition 3.4) together with the characterization of simple antimatter monoids by the Perron property of α^{-1} (Theorem 4.5) and the recurrence construction that forces principal ideals to be comparable (Theorem 5.3).
What would settle it
Exhibit a simple algebraic α in (0,1) whose reciprocal is a Perron number with no other positive conjugates, yet two elements of M_α generate incomparable principal ideals (or vice versa).
Extended reading notes
Core claim
For any algebraic α the monoid M_α is antimatter if and only if it is isomorphic to a finite product of isomorphic valuation monoids; when α∈(0,1) those valuation monoids are exactly the ones for which α^{-1} is a Perron number having no positive conjugate other than itself. The same conditions characterize when M_α is itself a valuation monoid, and the corresponding parameters are dense in (0,1).
Load-bearing premise
The argument needs that a simple polynomial cannot have several roots of the same maximal modulus, so that the product decomposition into simple factors preserves the Perron characterization.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper continues the study of the additive monoids M_α = {p(α) : p ∈ N_0[x]} for algebraic α, focusing on the antimatter (atomless) case and the valuation property. After reducing via Proposition 3.4 to the case of simple minimal polynomials, the authors prove that for α ∈ A ∩ (0,1) the monoid M_α is simple antimatter if and only if α^{-1} is a Perron number with no other positive conjugate (Theorem 4.5), and that this is further equivalent to M_α being a valuation monoid (Theorem 5.6). The non-simple case is recovered by writing M_α as a finite product of isomorphic valuation monoids (Corollary 4.6 and Theorem 5.6(2)). The proofs rely on Descartes’ rule, Gauss’s lemma, closed forms of linear recurrences, and Boyd’s theorem on maximal-modulus roots; two fully worked examples illustrate the λ eq 0 and λ = 0 cases of the key recurrence construction (Theorem 5.3). Density of the valuation set V inside (0,1) is established by an explicit family of simple Perron polynomials Q_{k,d,n}.
Significance. The work supplies clean, algebraic characterizations that complete the atomic/antimatter dichotomy begun in Correa-Morris–Gotti (2022) and place the valuation monoids M_α inside the classical hierarchy of GCD and pre-Schreier monoids. The reduction to simple polynomials, the explicit recurrence constructions that convert an arbitrary difference into a nonnegative polynomial, and the density theorem for V are all new and of independent interest for the arithmetic of Puiseux-type monoids and for the theory of Perron numbers. The arguments are fully written out with intermediate lemmas and concrete numerical examples, making the results immediately usable by researchers working on factorization in additive monoids.
minor comments (5)
- In the proof of Proposition 4.4 the matrix D is displayed with a somewhat crowded last row; a short sentence clarifying that the binomial coefficients arise from the integer-valued basis of C(x) would improve readability.
- Theorem 5.3 assumes the existence of a simple polynomial n(x) ∈ xN_0[x]-1 of degree at least deg p; while Lemma 3.3 guarantees this, a one-line forward reference at the beginning of the proof would help the reader.
- In Example 5.5 the closed form of a_j is lengthy; it would be enough to record that λ = 0 and that the remaining roots are roots of unity of order dividing 8, rather than writing every coefficient.
- The notation w_α(x) for the primitive integer multiple of m_α(x) is introduced in Proposition 4.2 but used earlier in the statement of Proposition 4.4; a brief forward pointer would avoid a momentary ambiguity.
- A few typographical inconsistencies appear (e.g., “V aluation” with a space in the section heading, and occasional missing spaces after commas in multi-line displays). These are purely cosmetic.
Circularity Check
No significant circularity: characterizations of antimatter/valuation monoids follow from definitions plus classical tools (Descartes, Gauss, recurrences, Boyd); self-citations to prior atomicity paper supply only independent background.
full rationale
The paper's central claims (Theorems 4.5/5.6, Corollary 4.6) equate absence of atoms in M_α with an isomorphism to a product of valuation monoids, and further equate the simple case (α∈(0,1)) with α^{-1} being a Perron number having no other positive conjugates. These are obtained by direct arguments: existence of an antimatter decomposition (polynomial in xN_0[x]-1) via Descartes and content arguments (Props. 4.1–4.2), construction of a simple multiple via linear recurrences and asymptotic dominance of the Perron root (Prop. 4.4), and the converse valuation property by the same recurrence technique that forces non-negative coefficients when the difference is positive (Thm. 5.3). The reduction to simple polynomials (Prop. 3.4) is an explicit monoid isomorphism, after which Boyd's external theorem applies cleanly. Self-citations to the authors' earlier paper [13] are used solely for the already-proved dichotomy “atomic or antimatter” and for the characterization of the atomic/factorial cases; they do not encode or force the new Perron/valuation equivalences. No parameter is fitted to data and then re-used as a prediction, no uniqueness theorem is imported solely from overlapping authors to forbid alternatives, and no known empirical pattern is merely renamed. The density construction (Thm. 5.10) builds its own explicit simple Perron examples. The derivation is therefore self-contained against external classical benchmarks; the single minor self-citation for background raises the score only to 1.
Assumptions & free parameters
assumptions (5)
- standard math Descartes' rule of signs: number of positive roots has the same parity as and is at most the number of sign variations.
- standard math Gauss's lemma: product of primitive polynomials over a GCD domain is primitive.
- standard math Closed-form solutions of linear homogeneous recurrences are linear combinations of n^j
ho^n for roots
ho of the characteristic polynomial.
- domain assumption A simple polynomial cannot have two distinct roots of maximal modulus (Boyd).
- domain assumption Perron numbers are closed under addition and multiplication (Lind).
Cite this review
Pith. "Pith review of On the additive structure of algebraic valuations of polynomial semirings II." pith.science (2026). https://pith.science/paper/EB53V5ZI
@misc{pith2026260702874,
author = {Pith},
title = {Pith review of: On the additive structure of algebraic valuations of polynomial semirings II},
year = {2026},
howpublished = {\url{https://pith.science/paper/EB53V5ZI}},
note = {Machine review of arXiv:2607.02874}
}
abstract
For $\alpha \in \mathbb{C}$, let $\mathbb{N}_0[\alpha]$ be the subsemiring of~$\mathbb{C}$ obtained as a homomorphic image of the $\alpha$-evaluation map $\mathbb{N}_0[x] \to \mathbb{C}$ defined as $p(x) \mapsto p(\alpha)$ for each polynomial $p(x) \in \mathbb{N}_0[x]$. Fundamental arithmetic and atomic aspects of the additive structure of $\mathbb{N}_0[\alpha]$ were first studied by the second author and Correa-Morris (2022). In this paper, we continue the investigation, now from the valuation-theoretic perspective. We show that for any algebraic number $\alpha$, the additive monoid of $\mathbb{N}_0[\alpha]$ contains no additive irreducibles if and only if it is isomorphic to the direct product of finitely many isomorphic valuation monoids (monoids whose principal ideals form a chain under inclusion). For any algebraic number $\alpha \in (0,1)$, these valuation monoids are precisely those where $\alpha^{-1}$ is a Perron number having no positive conjugates other than itself. In addition, we offer a description of the algebraic parameters $\alpha$ for which the additive structure of $\mathbb{N}_0[\alpha]$ is a valuation monoid. Finally, we argue that the subset of $(0,1)$ consisting of all algebraic parameters $\alpha$ such that the additive structure of $\mathbb{N}_0[\alpha]$ is a valuation monoid is dense in $(0,1)$.
Figures
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Works this paper leans on
-
[1]
A. C. Aitken,Determinants and Matrices, 9th ed., Interscience Pub. (1956)
1956
-
[2]
Ajran, J
K. Ajran, J. Bringas, B. Li, E. Singer, and M. Tirador,Factorization in additive monoids of evaluation polynomial semirings, Comm. Algebra51(2023) 4347–4362
2023
-
[3]
Akiyama and A
S. Akiyama and A. Peth˝ o,On the distribution of polynomials with bounded roots I. Polynomials with real coeffi- cients, J. Math. Soc. Japan66(2014) 927–949
2014
-
[4]
Akiyama and A
S. Akiyama and A. Peth˝ o,On the distribution of polynomials with bounded roots II. Polynomials with integer coefficients, Unif. Distrib. Theory9(2014) 5–19
2014
-
[5]
Albizu-Campos, J
S. Albizu-Campos, J. Bringas, and H. Polo,On the atomic structure of exponential Puiseux monoids and semirings, Comm. Algebra49(2021) 850–863
2021
-
[6]
D. D. Anderson, D. F. Anderson, and M. Zafrullah,Factorizations in integral domains, J. Pure Appl. Algebra69 (1990) 1–19
1990
-
[7]
Bert´ ok, L
C. Bert´ ok, L. Hajdu, and A. Peth˝ o,On the distribution of polynomials with bounded height, J. Number Theory 179(2017) 172–184
2017
-
[8]
D. W. Boyd,Irreducible polynomials with many roots of maximal modulus, Acta Arith.68(1994) 85–88
1994
Show all 26 references
-
[9]
Brauer,On algebraic equations with all but one root in the interior of the unit circle
A. Brauer,On algebraic equations with all but one root in the interior of the unit circle. To my teacher and former colleague Erhard Schmidt on his 75th birthday., Math. Nachr.4(1950) 250–257
1950
-
[10]
S. T. Chapman, F. Gotti, and M. Gotti,Factorization invariants of Puiseux monoids generated by geometric sequences, Comm. Algebra48(2020) 380–396
2020
-
[11]
S. T. Chapman, F. Gotti, M. Gotti, and H. PoloOn three families of dense Puiseux monoids. In: Ideal Theory and Arithmetic of Rings, Monoids, and Semigroups (Proceedings of the UMI-AMS Special Session at Palermo). Preprint on arXiv: https://arxiv.org/abs/1701.00058
-
[12]
P. M. Cohn,Bezout rings and their subrings, Proc. Cambridge Philos. Soc.64(1968) 251–264
1968
-
[13]
Correa-Morris and F
J. Correa-Morris and F. Gotti,On the additive structure of algebraic valuations of polynomial semirings, J. Pure Appl. Algebra226(2022) 107104
2022
-
[14]
Coykendall, D
J. Coykendall, D. E. Dobbs, and B. Mullins,On integral domains with no atoms, Comm. Algebra27(1999) 5813–5831
1999
-
[15]
P. Cull, M. Flahive, and R. Robson,Difference Equations: From Rabbits to Chaos, Undergrad. Texts Math.111 (2005)
2005
-
[16]
Dubickas,On roots of polynomials with positive coefficients, Manuscripta Math.123(2007) 353–356
A. Dubickas,On roots of polynomials with positive coefficients, Manuscripta Math.123(2007) 353–356
2007
-
[17]
Dubickas,On the number of monic integer polynomials with given signature, Arch
A. Dubickas,On the number of monic integer polynomials with given signature, Arch. Math.110(2018) 333–342
2018
-
[18]
S. N. Elaydi,An Introduction to Difference Equations(3rd ed.), Undergrad. Texts Math. (2004)
2004
-
[19]
Geroldinger, F
A. Geroldinger, F. Gotti, and S. Tringali,On strongly primary monoids, with a focus on Puiseux monoids, J. Algebra567(2021) 310–345
2021
-
[20]
Gotti and M
F. Gotti and M. Gotti,Atomicity and boundedness of monotone Puiseux monoids, Semigroup Forum96(2018) 536–552. 30T. CHEN, F. GOTTI, T. LU, & A. YAO
2018
-
[21]
Gotti and B
F. Gotti and B. Li,Divisibility and a weak ascending chain condition on principal ideals. Preprint on arXiv: https://arxiv.org/abs/2212.06213
-
[22]
Handelman,Spectral radii of primitive integral companion matrices and log concave polynomials, Symbolic Dynamics and its Applications, Contemp
D. Handelman,Spectral radii of primitive integral companion matrices and log concave polynomials, Symbolic Dynamics and its Applications, Contemp. Math.135(1992) 223–228
1992
-
[23]
Jiang, B
N. Jiang, B. Li, and S. Zhu,On the primality and elasticity of algebraic valuations of cyclic free semirings, Internat. J. Algebra and Comput.33(2023) 197–210
2023
-
[24]
D. A. Lind,The entropies of topological Markov shifts and a related class of algebraic integers, Ergod. Th. & Dynam. Sys.4(1984), 283–300
1984
-
[25]
Parks and D
H. Parks and D. Wills,The generalized Binet formula fork-bonacci numbers, Elem. Math.79(2023)
2023
-
[26]
E. S. Selmer.On the irreducibility of certain trinomials, Math. Scand.4(1956), 287–302. PRIMES-USA, MIT, Cambridge, MA 02139 Email address:ctimothy@mit.edu Department of Mathematics, MIT, Cambridge, MA 02139 Email address:fgotti@mit.edu PRIMES-USA, MIT, Cambridge, MA 02139 Ema...
1956
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