How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Simultaneous global synchronization from connectivity
Statement
Assume countable choice. In the uniform random edge-addition process on vertices, let be the first index at which is connected. With probability tending to one as , every graph with is simultaneously globally synchronizing. This is one event controlling all later indices.
Here phases belong to . For a simple graph with adjacency , globally synchronizing means that, for almost every initial phase with respect to normalized phase volume, the unit-coupling homogeneous Kuramoto solution converges in to a configuration in which all phases agree. The graph probability and initial-phase measure are separate; the simultaneous assertion is about graphs with this almost-everywhere deterministic property.
Facts & Assumptions
The edge process and high-probability convention are those of Uniform edge orderings, graph-process times and independent labels and Asymptotic quantifiers and uniform parameter ranges. Its exponential-clock form and all-index transfer are given by Exponential clocks and the uniform edge-order process.
Phase configurations and normalized phase volume are defined in Finite phase tori, local lifts and the flat metric and Normalized phase volume and almost-everywhere assertions. Smooth periodic potentials have complete unique trajectories under countable choice by Gradient trajectories and complete compact phase dynamics and The Axiom of Countable Choice (AC_ω).
Hoffman–Kahle–Paquette, Theorem 6.1 at , , gives a constant and a single event of probability tending to one on which, for every with , the normalized-Laplacian eigenvalues after deletion of isolated vertices satisfy . At every connected time no vertices are deleted. This is the first exact external input recorded below.
McRae, Theorem 3.4, states that a graph with positive degrees and is globally synchronizing whenever its normalized nonzero Laplacian condition number is less than two. Its model is the phase model above with a positive global coupling constant; take that constant equal to one. This is the second exact external input recorded below.
The normalized-Laplacian definitions and connectedness criteria are supplied by Normalized graph Laplacian and its nontrivial spectrum and Support connectivity and the unnormalized Laplacian kernel. The local transfer lemma Uniform spectral control transfers past connectivity combines a uniform connected-time spectral event with a deterministic condition-number criterion.
Sine and cosine are -periodic, satisfy and , and satisfy ; finite sums may be differentiated termwise (Phasors, trigonometric identities and periodic derivatives). Repeated differentiation therefore gives continuous derivatives of every order for each cosine of an angular coordinate difference.
Proof
Given: The objects and hypotheses in the statement.
Goal: Establish all stated claims.
For each fixed graph, put . By [F6], this finite sum is periodic in every angular coordinate and has continuous derivatives of every order, so it defines a smooth potential on the phase torus of [F2]. Differentiating the two ordered contributions for each edge, using and the oddness of sine, gives . Oddness follows from in the phasor identities of [F6]. Thus [F2] gives the complete unique trajectories used in the statement. Its phase-volume convention is normalized Lebesgue volume on a fundamental angular box, the almost-everywhere phase convention in [F4].
Set to mean the global-synchronization property just specified for a connected graph. Such a graph has positive degrees. By [F5], its unnormalized Laplacian has a single zero eigenvalue and all others positive, so . Therefore [F4] gives the deterministic implication with every hypothesis satisfied.
In the exponential-clock coupling of [F1], apply [F3] with . At every connected time after this is the required bound on for the full normalized Laplacian of [F5]. The event controls all such times together, rather than just any fixed time. Thus the hypotheses of the local uniform-spectrum transfer in [F5] hold for the predicate in step 2.1.
The transfer lemma now gives, with probability tending to one, for every index from through simultaneously. Each is the deterministic almost-everywhere phase property, so this event is precisely the graph event asserted in the statement.
External input
The two imported premises are exactly the uniform normalized-spectrum result in [F3] and the deterministic synchronization criterion in [F4]. Their complete source contracts appear in the metadata. The process coupling, the pre-onset isolated-vertex estimate, the spectral-window arithmetic and the all-index application are local arguments.
Source notes
The simultaneous hitting-time result was established by Jain, Mizgerd and Sawhney in Theorem 1.2 of The random graph process is globally synchronizing. Their original proof uses the defective-expander criterion of Theorem 1.6 and its random-process application in Sections 2–3. This citation records historical attribution; it is not a premise of the proof above.
The independent normalized-Laplacian composition above follows the route identified by McRae in Section 3.4.2; his deterministic argument is in Section 6.1. It combines the Hoffman–Kahle–Paquette spectral input with McRae's synchronization criterion and the local transfer lemmas. This does not describe the method used by Jain, Mizgerd and Sawhney.
Depends on
- Uniform edge orderings, graph-process times and independent labels
- Asymptotic quantifiers and uniform parameter ranges
- Finite phase tori, local lifts and the flat metric
- Normalized phase volume and almost-everywhere assertions
- Gradient trajectories and complete compact phase dynamics
- The Axiom of Countable Choice (AC_ω)
- Normalized graph Laplacian and its nontrivial spectrum
- Support connectivity and the unnormalized Laplacian kernel
- Exponential clocks and the uniform edge-order process
- Uniform spectral control transfers past connectivity
- Phasors, trigonometric identities and periodic derivatives
- Christopher Hoffman, Matthew Kahle and Elliot Paquette, Spectral gaps of random graphs and applications · Section 6, Theorem 6.1 specialized to k=1 and delta=1/4; process and t0 definitions immediately preceding it (PDF pp. 22–23); compare Theorem 1.3 and following paragraph (PDF p. 3)
- Andrew D. McRae, Benign landscapes for synchronization on spheres via normalized Laplacian matrices · Theorem 3.4, positive implication for normalized Laplacian (PDF p. 10); Theorem 2.1 and complete proof Section 6.1 (PDF pp. 19–22); dynamics interface Section 1.2 (PDF p. 3); process application Section 3.4.2 (PDF p. 11)
- Vishesh Jain, Clayton Mizgerd and Mehtaab Sawhney, The random graph process is globally synchronizing · Theorem 1.2 and preceding process definition (PDF p. 2); Section 1.3 (PDF p. 4); Theorem 1.6 (PDF p. 3) and Sections 2–3 (PDF pp. 4–11)
Dependency tree · 2 levels
Each result is drawn at its shortest distance from this item. Arrows run from prerequisites to the items that use them; this item has a heavier outline. External source nodes link directly to the cited text. The view shows up to two dependency steps; open a prerequisite to continue.
External dependencies
For independent rate-one exponential edge clocks, put p(t)=1-exp(-t), d(t)=(n-1)p(t), and p(t0)=(1/2+delta)log(n)/n with fixed delta in (0,1/2). There is C=C(1,delta) independent of n such that, with probability tending to one, for every t>=t0 simultaneously, deleting isolated vertices from the graph leaves a normalized Laplacian whose eigenvalues other than its single zero eigenvalue obey max_{i>1}|1-lambda_i|<C/sqrt(d(t)). In particular this bound applies to the full graph whenever that graph is connected.
Hypotheses: The k=1 continuous-time Erdos–Renyi edge process on n vertices with independent Exp(1) clocks; fixed delta in (0,1/2); asymptotics n tending to infinity. Here delta=1/4, so p(t0)=3log(n)/(4n).
Reading limits: Checked the arXiv v6 process definitions and Theorem 6.1 (PDF pp. 22–23), including k=1, the all-time quantifier, t0 and d(t); compared Theorems 1.1 and 1.3. Imported as an established theorem. This check does not reconstruct the Section 6 proof, its underlying estimates, or the topology applications.
Let A be a real symmetric adjacency matrix with strictly positive vertex degrees, D=diag(A1), L=D-A and normalized Laplacian calL=I-D^(-1/2) A D^(-1/2). If lambda_2(L)>0 and lambda_n(calL)/lambda_2(calL)<2, the homogeneous Kuramoto network with coupling A and any fixed positive global coupling constant is globally synchronizing: almost every initial phase converges to a fully synchronized configuration.
Hypotheses: Finite graph with at least two vertices, symmetric nonnegative unit adjacency weights in the present application, strictly positive degrees, lambda_2(L)>0 and strict normalized nonzero condition number less than two. The dynamics are homogeneous, in a co-rotating frame, with global coupling constant K>0 (here K=1).
Reading limits: Checked the positive implication of Theorem 3.4 (PDF p. 10), the dynamics and almost-everywhere convention in Section 1.2 including footnote 3 (PDF p. 3), and the process application and historical attribution in Section 3.4.2 (PDF p. 11). Imported as an established deterministic theorem; this check does not reconstruct Section 6.1 or its cited dynamical-systems results.
Theorem 1.2 establishes, with high probability, global synchronization simultaneously for all edge indices at or after connectivity. The original proof uses the defective-expander criterion of Theorem 1.6 and its random-process application in Sections 2–3. This citation supplies historical attribution only.
Hypotheses: The process starts from the empty simple graph on n vertices and adds a uniformly chosen missing edge at each step; tau is its first connected index; n tends to infinity. Global synchronization is almost-everywhere convergence in the homogeneous unit-coupling Kuramoto model.
Reading limits: Checked the title, authors, phase-model convention, Theorem 1.2, Theorem 1.6, the Section 1.3 proof organization, Section 2.1 strategy and Section 3 application. Did not reconstruct the original defective-expander proof or import its intermediate claims as premises.
Sources
- Christopher Hoffman, Matthew Kahle and Elliot Paquette, Spectral gaps of random graphs and applications · Section 6, Theorem 6.1 specialized to k=1 and delta=1/4; process and t0 definitions immediately preceding it (PDF pp. 22–23); compare Theorem 1.3 and following paragraph (PDF p. 3)
- Andrew D. McRae, Benign landscapes for synchronization on spheres via normalized Laplacian matrices · Theorem 3.4, positive implication for normalized Laplacian (PDF p. 10); Theorem 2.1 and complete proof Section 6.1 (PDF pp. 19–22); dynamics interface Section 1.2 (PDF p. 3); process application Section 3.4.2 (PDF p. 11)
- Vishesh Jain, Clayton Mizgerd and Mehtaab Sawhney, The random graph process is globally synchronizing · Theorem 1.2 and preceding process definition (PDF p. 2); Section 1.3 (PDF p. 4); Theorem 1.6 (PDF p. 3) and Sections 2–3 (PDF pp. 4–11)