Alphabeta Math

Expander Graphs and Constraint Graphs

About this page
Pipeline-generated
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.

1 · Prerequisites
2 · Logical flowchart

3 · Items

Definition

Regular multigraph and normalized adjacency

Lemma

Constant vector is a top eigenvector

Definition

Spectral edge and vertex expansion

Theorem

Expander mixing lemma

Lemma

Cheeger indicator and positive part energy

Lemma

Cheeger sweep and layer cake

Theorem

Cheeger inequalities for finite regular graphs

Corollary

Expander independent sets coloring and diameter

Definition

Margulis gabber galil graph

Lemma

Margulis family is constant degree and neighbor computable

Definition

Finite torus fourier transform

Lemma

Finite torus fourier orthogonality and affine change

Lemma

Fourier analysis of margulis adjacency

Lemma

Margulis diamond weight bound

Theorem

Margulis family has uniform spectral gap

Lemma

Expander size adjustment and laziness

Corollary

Explicit polynomial time constant degree expanders exist

Definition

Constraint graph and labeling value

Definition

Constraint graph regularization

Lemma

Cloud plurality rounding

Lemma

Regularization preserves value quantitatively

Lemma

Constraint expander overlay

Definition

Graph power and walk constraint

Lemma

Expander walk contraction

Lemma

Expander walk restricted operator

Theorem

Expander walk hits dense bad sets

Proposition

Expander walk sampled and moving sets

Lemma

Expander walk bad edge return

Proposition

Expander walk hits bad edges

Definition

Gap csp

False statement

Nonconstructive expanders suffice for uniform reductions

Sources