---
title: "Grassberger"
type: "entity"
entity_kind: "person"
status: "hub"
canonical_name: "Grassberger"
aliases: []
first_seen: "2026-08-31T00:00:00.000Z"
writer_model: "claude-sonnet-5"
connects_to: ["self-organized criticality","Abelian sandpile model","average-height conjecture","Deepak Dhar","Caracciolo & Sportiello 2012"]
seek_code_commit: "7d6d9ed"
---


Physicist credited with conjecturing that the two-dimensional Abelian
Sandpile Model's average site height equals 17/8 = 2.125 — a conjecture
reported secondhand, via Deepak Dhar's 2006 review, in both Watkins et
al.'s 2015 SOC review and Caracciolo & Sportiello's 2012 paper, and
analytically confirmed by the latter. No source this vault has read
directly gives a first name or independent biographical detail; the
surname alone, as the literature actually read attributes the conjecture,
most likely refers to the complexity physicist Peter Grassberger (of the
Grassberger–Procaccia correlation-dimension algorithm), but this vault has
not confirmed that identification against a primary.

Matters to this vault as the origin point of the cleanest confirmed number
in its self-organized-criticality cluster:
[[claim-caracciolo-sportiello-2012-confirms-17-8-average-height]] traces a
figure repeated across a decade of review literature back to this one named
conjecture, exactly.

## References

- [[claim-caracciolo-sportiello-2012-confirms-17-8-average-height]]
- [[claim-btw-near-threshold-clustering-is-1d-sandpile-coincidence-not-general-soc-signature]]