AURORA: Neuro-Symbolic Continual Indexing for Evolving RAG Systems

Manoj Saravanan, Rohit Kumar Salla, Ramya Manasa Amancherla


Abstract
Retrieval-Augmented Generation (RAG) systems depend on non-parametric indices to access external knowledge, yet most retrieval infrastructure assumes a stationary query document distribution after index construction. In dynamic settings involving continual knowledge updates or evolving terminology, this assumption often fails, leading to degraded retrieval performance, while full re-indexing remains computationally expensive. We propose AURORA, a neuro-symbolic framework for adapting retrieval indices under distribution shift by treating index maintenance as a few-shot continual learning problem. AURORA decouples discrete index structure from continuous metric representations, enabling efficient adaptation of neural components while preserving index topology. A lightweight Bayesian routing policy further balances stability and plasticity by dynamically selecting among adaptive neural indices and static fallbacks based on uncertainty estimates. Across dense, learned sparse (SPLADE), and generative (DSI) retrieval settings, AURORA recovers up to +26.9% Recall@10 on novel topics compared to static baselines, while adapting significantly faster than full retraining (28 ms vs. 5.1 s).
Anthology ID:
2026.findings-acl.495
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Publisher:
Association for Computational Linguistics
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Pages:
10179–10195
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.495/
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Cite (ACL):
Manoj Saravanan, Rohit Kumar Salla, and Ramya Manasa Amancherla. 2026. AURORA: Neuro-Symbolic Continual Indexing for Evolving RAG Systems. In Findings of the Association for Computational Linguistics: ACL 2026, pages 10179–10195, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
AURORA: Neuro-Symbolic Continual Indexing for Evolving RAG Systems (Saravanan et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.495.pdf
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