Sampling from multi-modal distributions with polynomial query complexity in fixed dimension via reverse diffusion
- URL: http://arxiv.org/abs/2501.00565v3
- Date: Thu, 23 Oct 2025 16:18:04 GMT
- Title: Sampling from multi-modal distributions with polynomial query complexity in fixed dimension via reverse diffusion
- Authors: Adrien Vacher, Omar Chehab, Anna Korba,
- Abstract summary: We provide the first sampling algorithm for a broad class of distributions.<n>Our algorithm simulates a time-reversed diffusion process.<n>It avoids metastability, requires no prior knowledge of the mode locations, and relaxes the well-known log-smoothness assumption.
- Score: 16.463220658992064
- License: http://creativecommons.org/publicdomain/zero/1.0/
- Abstract: Even in low dimensions, sampling from multi-modal distributions is challenging. We provide the first sampling algorithm for a broad class of distributions -- including all Gaussian mixtures -- with a query complexity that is polynomial in the parameters governing multi-modality, assuming fixed dimension. Our sampling algorithm simulates a time-reversed diffusion process, using a self-normalized Monte Carlo estimator of the intermediate score functions. Unlike previous works, it avoids metastability, requires no prior knowledge of the mode locations, and relaxes the well-known log-smoothness assumption which excluded general Gaussian mixtures so far.
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