---
license: other
license_name: polyform-noncommercial
license_link: LICENSE
language:
- en
tags:
- interpretability
- deception-detection
- mechanistic-interpretability
- safety
- elk
arxiv: 2606.17229
---

# Rift: A Conflict Signature for Deception in Language Models

**ELK-relevant result.** A model that *lies while knowing the truth* is in a measurably
different internal state than a model that is *simply wrong*. The difference is
large, per-example, and **label-free**.

**arXiv:** [2606.17229](https://arxiv.org/abs/2606.17229)  
**GitHub:** [omibranch/rift](https://github.com/omibranch/rift)  
**Demo:** [Omibranch/rift-demo](https://huggingface.co/spaces/Omibranch/rift-demo)

## Key results

| Result | Value |
|---|---|
| Label-free lie identification | **100%** (GPT-2 small, 3 seeds + natural Qwen) |
| Length-controlled AUC (Qwen2.5-1.5B) | **1.000**, orientation 20/20, p ≈ 9.5e-7 |
| Phi-3-mini AUC lie vs honest | **1.000** (34/34, p ≈ 6e-11) |
| Phi-3-mini AUC lie vs hallucination | **1.000** |
| Cross-lingual AUC (ru/zh/es/de, LC) | **1.000 in all 4 languages** |
| Cross-family AUC (3 architectures) | **0.933 mean**, all 6 pairs p < 0.001 |
| Strategic self-constructed deception | **AUC 1.0**, 24/24 Qwen-7B |
| Concealment countermeasure | **Fails** — conceal-AUC 1.0 |

## Method

**Residual rank** — fraction of signal outside the top-8 singular vectors of
hidden states — is elevated when a model maintains conflicting representations
(truth + false output) simultaneously.

```python
def residual_rank(H, k=8):
    _, s, _ = torch.linalg.svd(H.float(), full_matrices=False)
    return 1.0 - s[:k].sum() / s.sum()
```

## License

Dual-licensed: [PolyForm Noncommercial 1.0](LICENSE) for academic/research use.
Commercial use requires a separate license — see [LICENSE-COMMERCIAL.md](LICENSE-COMMERCIAL.md).

Copyright (c) 2026 Harmonic Labs (contact@harmoniclabs.cc)