Variational Lower Bound Training Objective

via “variational-lower-bound-training-objective”

* 🏆 2020: [An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale (ViT)](https://arxiv.org/abs/2010.11929)

Unique: DDPM derives the training objective from first principles using the variational lower bound, showing that the KL divergence terms simplify to an L2 loss on noise prediction when using a fixed linear noise schedule. This connection to score-matching provides both theoretical grounding and computational efficiency. The approach avoids the need for explicit likelihood computation or adversarial training, making it more stable than GANs.