Identifiability of Points and Rigidity of Hypergraphs under Algebraic Constraints

TL;DR

This paper introduces a unified framework combining graph rigidity and algebraic geometry to analyze the identifiability of points under algebraic constraints, applicable to hypergraphs and secant varieties.

Contribution

It develops necessary and sufficient hypergraph conditions for identifiability, bridging combinatorics, rigidity theory, and algebraic geometry in a novel way.

Findings

Established hypergraph conditions for point identifiability.

Analyzed effects of non-generic projections on secant varieties.

Unified framework applicable to various algebraic measurement scenarios.

Abstract

The identifiability problem arises naturally in a number of contexts in mathematics and computer science. Specific instances include local or global rigidity of graphs and unique completability of partially-filled tensors subject to rank conditions. The identifiability of points on secant varieties has also been a topic of much research in algebraic geometry. It is often formulated as the problem of identifying a set of points satisfying a given set of algebraic relations. A key question then is to prove sufficient conditions for relations to guarantee the identifiability of the points. This paper proposes a new general framework for capturing the identifiability problem when a set of algebraic relations has a combinatorial structure and develops tools to analyse the impact of the underlying combinatorics on the local or global identifiability of points. Our framework is built on the language of graph rigidity, where the measurements are Euclidean distances between two points, but applicable in the generality of hypergraphs with arbitrary algebraic measurements. We establish necessary and sufficient (hyper)graph theoretical conditions for identifiability by exploiting techniques from graph rigidity theory and algebraic geometry of secant varieties. In particular our work analyses combinatorially the effect of non-generic projections of secant varieties.