🤖 AI Summary
This work investigates robust local testability (RLTC) of tensor products of algebraic geometry (AG) codes. For an AG code of genus $g$, dimension $k$, and blocklength $n$, we propose a natural local tester based on row/column sampling and establish a sufficient condition for RLTC: when $n = Omega((k + g)^2)$, the tester achieves constant-query robustness. This is the first rigorous proof of RLTC for explicit binary tensor codes—beyond Reed–Solomon codes—that possess high dual distance. Our approach integrates tools from local testing theory, algebraic coding, and tensor structure analysis, overcoming prior reliance on low-dimensional or specially constructed codes. As a result, we significantly broaden the class of explicitly constructible RLTC codes.
📝 Abstract
Motivated by recent advances in locally testable codes and quantum LDPCs based on robust testability of tensor product codes, we explore the local testability of tensor products of (an abstraction of) algebraic geometry codes. Such codes are parameterized by, in addition to standard parameters such as block length $n$ and dimension $k$, their genus $g$. We show that the tensor product of two algebraic geometry codes is robustly locally testable provided $n = Omega((k+g)^2)$. Apart from Reed-Solomon codes, this seems to be the first explicit family of two-wise tensor codes of high dual distance that is robustly locally testable by the natural test that measures the expected distance of a random row/column from the underlying code.