REVIEW 2 major objections 6 minor 1 cited by
The polynomial growth of effective resistances in one-dimensional critical long-range percolation
T0 review · 2 major / 6 minor · reviewed 2026-08-16 · deepseek-v4-flash
Pith's one-line read Resistances grow as n^δ in critical long-range percolation
desk verdict The upper bound and the comparison machinery are genuinely new, but the lower-tail recursion in Proposition 5.8 relies on a false independence claim that currently breaks the supermultiplicativity argument. 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 load-bearing object is $\Lambda(n)=\max_{i,j\in[0,n)}\mathbb{E}[R_{[0,n)}(i,j)]$, the largest expected point-to-point resistance inside an interval of length $n$ when edges leaving the interval are ignored. The argument shows several resistances of interest are comparable to $\Lambda(n)$, and then proves that $\Lambda$ is almost multiplicative: $\Lambda(mn)\asymp \Lambda(m)\Lambda(n)$ up to constants depending only on $\beta$. Submultiplicativity comes from a renormalization of the line into blocks together with a comparison lemma stating that raising the conductance of one edge incident to a vertex cannot increase the current through any other incident edge. Supermultiplicativity is the harder direction: the paper introduces 'very good' intervals that force any unit flow to spend at least $\alpha m^\delta$ of energy, then uses a multi-scale coarse-graining argument to show that, with high probability, the rare bad intervals can be covered by 'good red animals' whose energy cost is negligible compared with the surrounding regions. Once $\Lambda$ is multiplicative up to constants, a standard subadditivity limit gives $\delta=\lim_n \log\Lambda(n)/\log n\in(0,1)$.
What would settle it
For a fixed $\beta$ and large $n=2^k$, compute $\mathbb{E}[R(0,[-n,n]^c)]$ (or estimate it by simulation over many samples) and check whether the ratio $\mathbb{E}[R(0,[-n,n]^c)]/n^{\delta}$ stays bounded away from $0$ and $\infty$ as $k\to\infty$, where $\delta$ is the slope of $\log\mathbb{E}[R(0,[-n,n]^c)]$ against $\log n$. If that slope fails to converge to a value in $(0,1)$, or if the ratio diverges along a subsequence, Theorem 1.1 is false.
Extended reading notes
Core claim
The central claim is Theorem 1.1: for every $\beta>0$ there is an exponent $\delta=\delta(\beta)\in(0,1)$, depending only on $\beta$, such that for all $n$ both $\mathbb{E}[R(0,[-n,n]^c)]\asymp_P R(0,[-n,n]^c)\asymp_P n^\delta$ and, conditionally on there being no edge between $[-n,n]$ and $[-2n,2n]^c$, $\mathbb{E}[R([-n,n],[-2n,2n]^c)\mid \text{no such edge}]\asymp_P R([-n,n],[-2n,2n]^c)\asymp_P n^\delta$. Here $\asymp_P$ means that for every $\varepsilon>0$ the ratio is bounded between constants with probability at least $1-\varepsilon$. The proof obtains $\delta$ by proving that the maximal expected point-to-point resistance $\Lambda(n)$ inside an interval of length $n$ is both submultiplicative and supermultiplicative up to constants, so a standard subadditivity argument yields $\delta=\lim_n \log\Lambda(n)/\log n$. The inequalities $0<\delta$ and $\delta<1$ are imported from earlier polynomial lower bounds and from the known chemical-distance exponent of the same critical model; the present contribution is showing that one well-defined exponent governs all these resistances and that point-to-box and conditioned box-to-box resistances are comparable to $\Lambda(n)$.
Load-bearing premise
The proof relies on earlier results giving a uniform high-probability polynomial lower bound on resistances and a separate bound showing the growth exponent is below 1; if either of those imported bounds failed for some value of $\beta$, the new exponent would not be guaranteed to lie in $(0,1)$.
Editorial extensions
If this is right
- For every $\beta>0$ the point-to-box resistance and the conditioned box-to-box resistance share one polynomial growth exponent $\delta(\beta)\in(0,1)$, so no separate exponent is needed for different resistance types.
- The lower-tail estimate of Corollary 1.2 holds: for sufficiently small $\varepsilon>0$, $P(R(0,[-n,n]^c)\ge\varepsilon n^\delta)\ge 1-\varepsilon^q$, so the resistance is bounded away from zero with overwhelming probability.
- The paper's resistance estimates place the critical one-dimensional model in position to support random-walk heat-kernel and spectral-dimension bounds by established resistance-form techniques, although the authors deliberately leave those derivations for later work.
- The internal exponents constructed in the proofs can be chosen non-increasing in $\beta$, as recorded in Remarks 3.4 and 4.2, so stronger coupling does not make the resistance grow faster in $n$ within the constructed family of exponents.
Reading between the lines
- A natural testable extension is whether $\delta(\beta)$ is strictly decreasing and, in particular, approaches $1$ as $\beta\to0$; the paper only records monotonicity, not limits.
- The same coarse-graining machinery, with $\Lambda(n)$ in place of the graph distance, may be adaptable to the two-dimensional critical model, where the analogous resistance exponent is not known; the paper does not make this claim.
- Because the model is exactly scale-invariant, the theorem suggests that the resistance metric itself may admit a scaling limit with a Hausdorff-type exponent $\delta(\beta)$, even though the paper notes that deriving such a limit remains a major open challenge.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper studies critical long-range percolation on Z with edge probability 1-exp(-β∫∫|u-v|^{-2}dudv) and unit conductances, and proves that the effective resistance from 0 to [-n,n]^c, as well as the conditioned box-to-box resistance from [-n,n] to [-2n,2n]^c, both grow like n^{δ(β)} for some δ(β)∈(0,1). The proof defines Λ(n) as the maximum expected point-to-point resistance in [0,n), establishes submultiplicativity (Prop. 2.1), a weak form of supermultiplicativity (Prop. 4.1), a second-moment bound (Prop. 5.1), comparability of point-to-point, point-to-box, and box-to-box resistances (Props. 5.4 and 5.8), and finally full supermultiplicativity (Prop. 6.1). The exponent δ is then obtained via Fekete's lemma. The lower endpoint δ>0 is imported from a strengthened lower-bound lemma (Lemma 3.3) based on [11], and the upper endpoint δ<1 is imported from [3].
Significance. If the main theorem holds, this is a substantial result: it gives the sharp polynomial growth exponent for effective resistances in the critical one-dimensional long-range percolation model, a quantity of direct relevance to random walks. The paper's architecture—defining Λ(n), proving sub- and supermultiplicativity, and then comparing several resistance types—is natural and is supported by several nontrivial technical contributions, notably the flow-comparison Lemma 2.2, the detailed submultiplicativity proof, and the second-moment bound for point-to-point resistances. The exposition is generally careful and well organized. However, the proof of the box-to-box lower tail in Proposition 5.8 contains a false independence assertion that is load-bearing for the rest of the paper, and Proposition 6.1 is only sketched. These gaps need to be addressed before the main claims can be considered established.
major comments (2)
- [§5.3, Proposition 5.8, after Eq. (5.38)] The proof asserts 'independence of R(...) for all odd k' and uses it to bound the probability that at least two of the annulus resistances R_k are below γ^3Λ(N) by M^2 max_i P(R_i < γ^3Λ(N))^2. This independence is false: for k and k+2, the target annulus of R_k is exactly the source annulus of R_{k+2}, and both resistances are decreasing functions of the common edge set E\ C_{\ge N}. By FKG, P(R_k < x, R_{k+2} < x) ≥ P(R_k < x)P(R_{k+2} < x), so the intersection probability can be of order the marginal rather than its square. Consequently the recursion leading to (5.40) and the lower-tail bound for R([-MN,MN],[-2MN,2MN]^c | A_{MN}) do not follow. Since Proposition 5.8 is used in Proposition 6.3 and in the proof of the main theorem, this gap directly threatens Theorem 1.1.
- [§6, Proposition 6.1] Proposition 6.1 is the second key ingredient in the proof of Theorem 1.1, but its proof is only a sketch: after stating the new very-good interval definition, the text says 'we will omit certain details' and then asserts the coarse-graining estimate (6.4), the properties (P1)-(P3), and inequality (4.46) without proof. The verification of these facts in the new setting is not a routine line-by-line copy of Section 4, because the definition of very-good intervals and the input Proposition 6.3 differ from Section 3. Since the supermultiplicativity of Λ(n) is essential for the existence of δ, this omission is load-bearing. The authors should either supply the full coarse-graining proof or state precisely which lemmas from Section 4 transfer unchanged and why.
minor comments (6)
- [§2.2, Eq. (2.19)] The notation E[·|bE] conditions on the edge set bE, but bE is not explicitly identified with a σ-algebra; please clarify that the conditional expectation is with respect to the σ-algebra generated by bE.
- [§3.3, proof of Proposition 3.2] There is an inconsistency in the constants: the text uses both e^{-3C4 m^{1/\log n}} and e^{-3C3 m^{1/\log n}} in the same proof. Please correct the notation.
- [§4.2, parameters in (4.10)-(4.13)] The parameters A, λ, a_k, b_k, b_{k-1,k}, and K_* are numerous and somewhat opaque; a short table or a summary of their roles would make the coarse-graining argument much easier to follow.
- [§5.3, Definition 5.9] The notation A^c_{2MN,MN} is used for the annulus [-2MN,2MN]\[-MN,MN], but the superscript 'c' normally denotes complement; please use a distinct symbol or define the notation explicitly.
- [§5.3, proof of Proposition 5.8] There are several typographical issues: 'at leat' should be 'at least', and 'hods' in Section 5.1 should be 'holds'. Please proofread the final version.
- [§7, proof of Theorem 1.1] The application of Fekete's lemma to the sequences a_k and b_k is correct, but a sentence justifying finiteness of log Λ(2^k) (e.g., by the boundedness of the resistance of a single edge) would improve the exposition.
Circularity Check
No circularity: the exponent delta is derived by Fekete's lemma from independently proven submultiplicativity and supermultiplicativity bounds, and the cited prior-work inputs do not assume the target theorem.
full rationale
The paper's central derivation is self-contained once Lemma 3.3 and the bound delta<1 are accepted as external inputs. Lambda(n) is defined directly from the model (Eq. 1.4), and Theorem 1.1's exponent delta is obtained in Section 7 as the Fekete limit of log Lambda(2^k)/log(2^k) using Proposition 2.1 (submultiplicativity) and Proposition 6.1 (supermultiplicativity). These propositions are proved through renormalization, coarse-graining, and resistance comparisons (Sections 2-6) that do not invoke the conclusion being proved. The main imported bounds are explicitly disclosed in Remark 1.3: delta>0 follows from the authors' prior work [11] and delta<1 follows from [3]. Lemma 3.3 is a strengthened form of [11, Theorem 1.1], but [11] is a separate, parameter-free lower-bound result whose assumptions do not include the existence of delta or the polynomial-growth conclusion; citing it is therefore legitimate external support, not circularity. The use of [3] for the sublinear bound Lambda(M) <= M/(100 C) in the proof of Proposition 5.8 is likewise an independent input, and the eventual Fekete argument does not reuse Proposition 5.8's conclusion as an assumption. The skeptic's objection about independence of annulus resistances in Proposition 5.8 is a correctness risk, not a circularity reduction: even if that independence failed, the claimed derivation would be invalid for probabilistic reasons, but it would not be equivalent to its inputs by construction. No equation is used to define Lambda and then reused as its own prediction, and no fitted parameter is relabeled as a derived exponent. Accordingly, the circularity score is 0.
Assumptions & free parameters
assumptions (4)
- domain assumption The edge probabilities are p_{i,j}=1-exp(-β ∫∫ |u-v|^{-2} du dv) for |i-j|>1 and p=1 for |i-j|=1, with edges independent.
- domain assumption Lemma 3.3: a slightly stronger version of [11, Theorem 1.1] gives high-probability polynomial lower bounds with constants c*, C*, δ* depending only on β.
- domain assumption δ<1 follows from [3] (Bäumler), presumably bounding resistance from above polynomially with exponent <1.
- standard math Standard tools: FKG inequality, BK inequality (van den Berg-Kesten), Chernoff bounds, Fekete's lemma, and the variational characterization of effective resistance [7, Prop 2.3].
Cite this review
Pith. "Pith review of The polynomial growth of effective resistances in one-dimensional critical long-range percolation." pith.science (2026). https://pith.science/paper/MLBGQ55F
@misc{pith2026250421378,
author = {Pith},
title = {Pith review of: The polynomial growth of effective resistances in one-dimensional critical long-range percolation},
year = {2026},
howpublished = {\url{https://pith.science/paper/MLBGQ55F}},
note = {Machine review of arXiv:2504.21378}
}
abstract
We study the critical long-range percolation on $\mathbb{Z}$, where an edge connects $i$ and $j$ independently with probability $1-\exp\{-\beta\int_i^{i+1}\int_j^{j+1}|u-v|^{-2}{\rm d} u{\rm d} v\}$ for $|i-j|>1$ for some fixed $\beta>0$ and with probability 1 for $|i-j|=1$. Viewing this as a random electric network where each edge has a unit conductance, we show that the effective resistances from 0 to $[-n,n]^c$ and from the interval $[-n,n]$ to $[-2n,2n]^c$ (conditioned on no edge joining $[-n,n]$ and $[-2n,2n]^c$) both grow like $n^{\delta(\beta)}$ for some $\delta(\beta)\in (0,1)$.
Figures
Figures from the paper (8 more)
Forward citations
Cited by 1 Pith paper
-
Spectral dimensions for one-dimensional critical long-range percolation
For critical long-range percolation on the integers, the quenched and annealed spectral dimensions of the random walk both exist and equal 2/(1 + δ), with δ the effective-resistance exponent from a companion paper.
Reference graph
Works this paper leans on
-
[3]
J. Bäumler. Distance in 1 ∥x−y∥2d percolation models for all dimensions.Commun. Math. Phys. , 404:1495– 1570, 2023
work page 2023
-
[11]
J. Ding, Z. Fan, and L.-J. Huang. Polynomial lower bound on the effective resistance for the one-dimensional critical long-range percolation. To appear inComm. Pure Appl. Math
-
[1]
M. Aizenman and C. Newman. Discontinuity of the percolation density in one-dimensional 1/|x−y|2 percolation models. Comm. Math. Phys. , 107:611–641, 1986
work page 1986
-
[2]
D.-J. Aldous and J.-A. Fill. Reversible Markov chains and random walks on graphs . 2002. URL www.berkeley.edu/users/aldous/book.html
work page 2002
-
[4]
J. Bäumler. Recurrence and transience of symmetric random walks with long-range jumps.Electron. J. Probab., 28(106):24 pp, 2023
work page 2023
-
[5]
N. Berger. Transience, recurrence and critical behavior for long-range percolation.Comm. Math. Phys. , 226(3):531–558, 2002
2002
-
[6]
N. Berger and Y. Tokushige. Scaling limits for random walks on long range percolation clusters. arXiv:2403.18532, 2024
arXiv 2024
- [7]
Show all 24 references
-
[8]
Can, D.A
V.H. Can, D.A. Croydon, and T. Kumagai. Spectral dimension of simple random walk on a long-range percolation cluster. Electron. J. Probab., 27(56):1–37, 2022
2022
-
[9]
Crawford and A
N. Crawford and A. Sly. Simple random walk on long-range percolation clusters II: scaling limits.Ann. Probab., 41(2):445–502, 2013
2013
-
[10]
D.A.Croydon.Scalinglimitsofstochasticprocessesassociatedwithresistanceforms. Ann. Inst. H. Poincaré Probab. Statist., 54(4):1939–1968, 2018
1939
-
[12]
J. Ding, Z. Fan, and L.-J. Huang. Uniqueness of the critical long-range percolation metrics. To appear in Memoirs of the AMS
-
[13]
Ding and E
J. Ding and E. Gwynne. Uniqueness of the critical and supercritical Liouville quantum gravity metrics. Proc. Lond. Math. Soc. , 126(1):216–333, 2023
2023
-
[14]
Ding and A
J. Ding and A. Sly. Distances in critical long range percolation. 2013. arXiv:1303.3995
2013 arXiv
-
[15]
Duminil-Copin, C
H. Duminil-Copin, C. Garban, and V. Tassion. Long-range models in 1d revisited.Ann. Inst. H. Poincaré Probab. Statist., 60(1):232–241, 2024
2024
-
[16]
Gwynne and J
E. Gwynne and J. Miller. Existence and uniqueness of the liouville quantum gravity metric forγ∈ (0, 2). Invent. Math., 223(1):213–333, 2021. 68 JIAN DING ZHERUI F AN LU-JING HUANG
2021
-
[17]
T. Kumagai. Random walks on disordered media and their scaling limits. École d’Été de Probabilités de Saint-Flour XL-2010. Lecture Nots in Mathematics 2101. Springer, Cham, 2014
2010
-
[18]
Kumagai and J
T. Kumagai and J. Misumi. Heat kernel estimates for strongly recurrent random walk on random media. J. Theor. Probab., 21:910–935, 2008
2008
-
[19]
Levin, Y
D.A. Levin, Y. Peres, and E.L. Wilmer.Markov chains and mixing times . Amer. Math. Soc., Providence, RI, 2009. With a chapter by J.G. Propp and D.B. Wilson
2009
-
[20]
J. Misumi. Estimates on the effective resistance in a long-range percolation onZd. J. Math. Kyoto Univ. , 48(2):389–400, 2008
2008
-
[21]
Newman and L.S
C.M. Newman and L.S. Schulman. One dimensional 1/|i−j|s percolation models: The existence of a transition fors≤ 2. Comm. Math. Phys. , 104(4):547–571, 1986
1986
-
[22]
Schulman
L.S. Schulman. Long-range percolation in one dimension.J. Phys. A: Math. Gen. , 16(17):L639–L641, 1983
1983
-
[23]
J.vandenBergandH.Kesten.Inequalitieswithapplicationstopercolationandreliability. J. Appl. Probab., 22(3):556–569, 1985
1985
-
[24]
Zhang, F.C
Z.Q. Zhang, F.C. Pu, and B.Z. Li. Long-range percolation in one dimension.J. Phys. A: Math. Gen. , 16(3):L85, 1983
1983
Reviewed August 16, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.