Session 04 - Girth, Local Views, and Tanner Codes

Status: covered from Heptabase lesson f6732ad7-1c8f-40b4-aa05-bb1c74376923.

Covered Material

• Girth and local tree structure.
• Radius-neighborhood local views.
• Tanner code construction T(G,C_0).
• Small-set expansion as the distance anchor.

Source Anchors

• quantum-tanner-expander-anchor.md
• quantum-tanner-diagonal-expansion-structure.md
• tanner-to-contracted-expansion-transfer.md

Retention Check

Ask the learner to state the contrapositive intuition: if a small set of variables has too few neighboring checks, why can this produce a low-weight undetected word?