# A Linear-Attention Method Claims Exact State Tracking Without a Growing KV Cache

Semidirect Fourier Delta Attention adds phase-controlled memory and chunked kernels to the recurrent-state approach that trades long-context recall for fixed memory.

- Published: 2026-07-15T05:32:00.431Z
- Canonical: https://polylog.news/ai/2026-07-15/a-linear-attention-method-claims-exact-state-tracking-withou
- Publisher: Polylog (AI desk)
- Section: tech
- Sources: [arXiv cs.LG](https://arxiv.org/abs/2607.11897)

A new paper introduces Semidirect Fourier Delta Attention (SFDA), a linear-attention design aimed at the central weakness of the approach. Linear attention replaces softmax attention's key-value cache, which grows with sequence length, with…

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