Nils Lukas
2026
SD-E2: Semantic Exploration for Reasoning Under Token Budgets
Kshitij Mishra | Nils Lukas | Salem Lahlou
Findings of the Association for Computational Linguistics: EACL 2026
Kshitij Mishra | Nils Lukas | Salem Lahlou
Findings of the Association for Computational Linguistics: EACL 2026
Forest Before Trees: Latent Superposition for Efficient Visual Reasoning
Yubo Wang | Juntian Zhang | Yichen Wu | Yankai Lin | Nils Lukas | Yuhan Liu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Yubo Wang | Juntian Zhang | Yichen Wu | Yankai Lin | Nils Lukas | Yuhan Liu
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
While Chain-of-Thought empowers Large Vision-Language Models with multi-step reasoning, explicit textual rationales suffer from an information bandwidth bottleneck, where continuous visual details are discarded during discrete tokenization. Recent latent reasoning methods attempt to address this challenge, but often fall prey to premature semantic collapse due to rigid autoregressive objectives. In this paper, we propose Laser, a novel paradigm that reformulates visual deduction via Dynamic Windowed Alignment Learning. Instead of forcing a point-wise prediction, Laser aligns the latent state with a dynamic validity window of future semantics. This mechanism enforces a "Forest-before-Trees" cognitive hierarchy, enabling the model to maintain a probabilistic superposition of global features before narrowing down to local details. Crucially, Laser maintains interpretability via decodable trajectories while stabilizing unconstrained learning via Self-Refined Superposition. Extensive experiments on 6 benchmarks demonstrate that Laser achieves state-of-the-art performance among latent reasoning methods, surpassing the strong baseline Monet by 5.03% on average. Notably, it achieves these gains with extreme efficiency, reducing inference tokens by more than 97%, while demonstrating robust generalization to out-of-distribution domains.
2025
SPIRIT: Patching Speech Language Models against Jailbreak Attacks
Amirbek Djanibekov | Nurdaulet Mukhituly | Kentaro Inui | Hanan Aldarmaki | Nils Lukas
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Amirbek Djanibekov | Nurdaulet Mukhituly | Kentaro Inui | Hanan Aldarmaki | Nils Lukas
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Speech Language Models (SLMs) enable natural interactions via spoken instructions, which more effectively capture user intent by detecting nuances in speech. The richer speech signal introduces new security risks compared to text-based models, as adversaries can better bypass safety mechanisms by injecting imperceptible noise to speech. We analyze adversarial attacks under white-box access and find that SLMs are substantially more vulnerable to jailbreak attacks, which can achieve a perfect 100% attack success rate in some instances. To improve security, we propose post-hoc patching defenses used to intervene during inference by modifying the SLM’s activations that improve robustness up to 99% with (i) negligible impact on utility and (ii) without any re-training. We conduct ablation studies to maximize the efficacy of our defenses and improve the utility/security trade-off, validated with large-scale benchmarks unique to SLMs.