Simulation-free and finite-time diffusion model
- URL: http://arxiv.org/abs/2608.03117v1
- Date: Tue, 04 Aug 2026 04:39:14 GMT
- Title: Simulation-free and finite-time diffusion model
- Abstract summary: We propose a framework for designing the reference process that achieves both simultaneously.<n>We show that conditional flow matching arises as the small-noise limit of the proposed framework.
- Score: 0.688204255655161
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: The performance of generative diffusion models is determined by the choice of the reference diffusion process connecting the empirical and prior distributions. Conventional approaches typically trade off simulation-free training against finite-time generation. We propose a framework for designing the reference process that achieves both simultaneously. The key idea is to prescribe tractable time-dependent conditional distributions and then construct the reference process realizing them as its marginals. This framework reveals that score matching is not fundamental to diffusion-model training but instead emerges naturally through reversal of the reference process. We further show that conditional flow matching arises as the small-noise limit of the proposed framework.
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