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arxiv: 2605.23308 · v1 · pith:WDFHOJKTnew · submitted 2026-05-22 · 🧮 math.PR

Convergence rate estimates for semigroups and heat kernels associated with resistance forms

Pith reviewed 2026-05-25 03:57 UTC · model grok-4.3

classification 🧮 math.PR
keywords convergence ratesresistance formsheat kernelssemigroupsGromov-Hausdorff-vague convergenceSierpinski gasketBouchaud trap modelhomogenization
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The pith

Explicit convergence rates are established for semigroups and heat kernels on resistance forms under measure regularity and lower resistance estimates.

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

The paper seeks to turn previous qualitative statements about convergence of heat kernels and semigroups into quantitative ones. When measured resistance metric spaces converge in the Gromov-Hausdorff-vague sense, the associated semigroups and heat kernels converge at explicit rates provided the spaces obey measure regularity and lower resistance estimates. A new metric is constructed that generates the same topology yet simplifies the task of obtaining the rates. The bounds are applied first to random-walk approximations of Brownian motion on the Sierpinski gasket, yielding the initial rate estimate for that setting. The same bounds are then used on the one-dimensional Bouchaud trap model, extending the range of parameters where homogenization is proved and sharpening the existing rate estimates by at least a quadratic factor.

Core claim

Under the assumptions of measure regularity and lower resistance estimates, explicit convergence rates hold for the semigroups and heat kernels whenever the underlying measured resistance metric spaces converge in the Gromov-Hausdorff-vague topology. A new metric is introduced that induces this topology and is convenient for evaluating the rates. The resulting bounds deliver the first convergence-rate estimate for random-walk approximation of Brownian motion on the Sierpinski gasket and extend the known parameter regime for homogenization in the one-dimensional Bouchaud trap model while improving prior rates by at least a quadratic factor.

What carries the argument

Quantitative bounds obtained from measure regularity together with lower resistance estimates, supported by a newly defined metric that induces the Gromov-Hausdorff-vague topology.

If this is right

  • First explicit rate estimate for random-walk approximation of Brownian motion on the Sierpinski gasket.
  • Homogenization proved for the one-dimensional Bouchaud trap model in every parameter regime where it occurs.
  • Existing convergence-rate estimates for the Bouchaud trap model improved by at least a quadratic factor.
  • A new metric simplifies direct calculation of distances in the Gromov-Hausdorff-vague topology.

Where Pith is reading between the lines

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

  • The rates supply concrete error controls that could be used to certify numerical discretizations of diffusions on fractals.
  • The same quantitative approach may transfer to other classes of Dirichlet forms once analogous regularity conditions are verified.
  • Improved rates in the trap model suggest that similar sharpening is possible for homogenization problems in higher-dimensional or non-one-dimensional settings.
  • The new metric could serve as a computational tool for checking convergence of other stochastic processes whose state spaces are resistance spaces.

Load-bearing premise

The measured resistance metric spaces satisfy measure regularity and lower resistance estimates.

What would settle it

A concrete sequence of spaces obeying measure regularity and lower resistance estimates whose semigroup or heat-kernel convergence is slower than the explicit rate given by the main theorem.

Figures

Figures reproduced from arXiv: 2605.23308 by Koyo Oishi.

Figure 1
Figure 1. Figure 1: Sierpinski Gasket Remark 1.15. We used the open set condition and the fact that the resistance metric and the Euclidean metric are comparable up to a power to verify Assumption 1.1 for the Sierpinski gasket. Note that (A2) or (A3) are satisfied provided that the connectivity of the space or the continuity of the process is established. Consequently, our results apply to a wider class of fractals satisfying… view at source ↗
Figure 2
Figure 2. Figure 2: Graph of the exponent E = E(α) appearing in the quenched estimate supx∈R |P0(X1 ≤ x) − P0(Xn 1 ≤ x)| ≲ n −E+ε . The blue line represents the exponent derived in [3], and the red line represents the one derived in Theorem 8.14. 2 Preliminaries 2.1 Bounded Lipschitz metric In this section, we introduce an appropriate metric on a space of measures. In [21], the Gromov-Hausdorff￾vague metric (or topology) is u… view at source ↗
Figure 3
Figure 3. Figure 3: Let V0 be the set of vertices of a regular triangle. We define Vn as Vn := ∪ 3 i=1fi(Vn−1), where the maps fi , i = 1, 2, 3 are defined at the beginning of this section. Note that µn can be expressed as µn({x}) = degVn (x) X y∈Vn degVn (y) , x ∈ Vn. Here, we denote the degree of a vertex x ∈ Vn in the graph Vn by degVn (x). We denote the log2 3- dimensional probability Hausdorff measure on K by µ. We write… view at source ↗
read the original abstract

In this paper, we derive quantitative convergence rates for stochastic processes associated with resistance forms. While the qualitative convergence of heat kernels and semigroups under the Gromov-Hausdorff-vague convergence of underlying measured resistance metric spaces has been investigated previously, their quantitative convergence rates have remained unexplored. We establish explicit convergence rates for the associated semigroups and heat kernels under the assumptions of measure regularity and lower resistance estimates. Furthermore, we introduce a new metric that induces the Gromov-Hausdorff-vague topology, and is convenient for evaluation. As applications of our main results, we present two illustrative examples. First, we derive first estimate on the convergence rate for the random walk approximation of Brownian motion on the Sierpinski gasket. Second, we apply our results to the one-dimensional Bouchaud trap model, successfully extending the previously known parameter regime to all cases where homogenization occurs and improving the convergence rate estimates in the existing regime by at least a quadratic factor.

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 / 2 minor

Summary. The paper derives explicit quantitative convergence rates for semigroups and heat kernels associated with resistance forms on measured resistance metric spaces, under the assumptions of measure regularity and lower resistance estimates. It introduces a new metric inducing the Gromov-Hausdorff-vague topology and applies the results to obtain a first convergence-rate estimate for the random-walk approximation of Brownian motion on the Sierpinski gasket, as well as an extension of the parameter regime (to all cases where homogenization occurs) together with a quadratic-factor improvement in the existing regime for the one-dimensional Bouchaud trap model.

Significance. If the derivations hold, the work supplies the first quantitative rates in a setting where only qualitative convergence under GHV convergence was previously available. The applications are concrete and improve upon existing results in the Bouchaud model while providing the initial rate for the gasket example. The new metric is presented as convenient for evaluation and may facilitate further quantitative work on resistance forms.

minor comments (2)
  1. [Abstract / Introduction] The abstract states that the results hold under measure regularity and lower resistance estimates, but the precise statements of these assumptions (and any uniformity requirements across the sequence of spaces) should be recalled explicitly in the introduction or §2 to make the hypotheses self-contained for readers.
  2. [Application section on Bouchaud model] The claim of a 'quadratic factor' improvement in the Bouchaud trap model should be accompanied by a direct comparison (in a table or remark) with the best previously published rate, citing the specific theorem or proposition being improved.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their summary of the manuscript and for acknowledging its potential significance in providing the first quantitative convergence rates under Gromov-Hausdorff-vague convergence for resistance forms, along with the concrete applications to the Sierpinski gasket and Bouchaud trap model. The recommendation is listed as uncertain, but the report contains no specific major comments or points of concern. We would be happy to address any particular questions or requests for clarification if provided.

Circularity Check

0 steps flagged

No significant circularity; derivation self-contained under stated assumptions

full rationale

The paper derives explicit quantitative convergence rates for semigroups and heat kernels on resistance forms, conditional on the external assumptions of measure regularity and lower resistance estimates. These assumptions are invoked as inputs to obtain the bounds rather than being redefined in terms of the rates themselves. The new metric inducing the GHV topology is introduced as a tool for evaluation, not as a self-referential construct. The two applications (Sierpinski gasket random walk and Bouchaud trap model) are presented as illustrative uses of the main results, with no indication that the claimed rates reduce to fitted parameters or prior self-citations by construction. The derivation chain remains independent of its outputs.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review; no explicit free parameters, axioms, or invented entities are identifiable.

pith-pipeline@v0.9.0 · 5687 in / 972 out tokens · 16048 ms · 2026-05-25T03:57:07.174636+00:00 · methodology

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