Stochastic Indexing Primitives for Non-Deterministic Molecular Archives
Faruk Alpay, Levent Sarioglu
TL;DR
This work addresses the challenge of scalable, content-addressable random access in DNA-based data archives. It introduces the Holographic Bloom Filter (HBF), a high-dimensional, associative index that binds key and value vectors via circular convolution and stores their superposed bindings in a single memory vector, enabling one-shot retrieval by correlation with a query key. The authors provide explicit construction and decoding algorithms, a signal–noise decomposition, and concentration/extreme-value analyses that yield threshold and margin settings with exponential error decay in the vector dimension under explicit noise models. They compare HBF to pointer-chasing baselines, discuss design trade-offs, robustness, and potential integration with traditional error correction, highlighting substantial reductions in retrieval latency and energy by leveraging parallel molecular interactions. Overall, HBF offers a concrete, analyzable framework for content-addressable indexing in DNA storage, with quantified trade-offs between dimensionality, dataset size, and noise, paving the way toward practical in-situ indexing primitives for molecular archives.
Abstract
Random access remains a central bottleneck in DNA-based data storage. Existing systems typically retrieve records by PCR enrichment or other multi-step biochemical procedures, which do not naturally support fast, massively parallel, content-addressable queries. We introduce the Holographic Bloom Filter (HBF), a probabilistic indexing primitive that stores key-pointer associations as a single high-dimensional memory vector. HBF binds a key vector and a value (pointer) vector using circular convolution and superposes bindings across all records. A query decodes by correlating the memory with the query key and selecting the best matching value using a margin-based decision rule. We give construction and decoding algorithms and a probabilistic analysis under explicit noise models (memory corruption and query/key mismatches). The analysis provides concentration bounds for match and non-match score distributions, explicit threshold and margin settings for a top K decoder, and exponential error decay in the vector dimension under standard randomness assumptions. HBF offers a concrete, analyzable alternative to pointer-chasing molecular data structures, enabling one-shot associative retrieval while quantifying trade-offs among dimensionality, dataset size, and noise.
