{"slug": "across-the-loss-landscape-with-progressive-growth", "title": "Across the Loss Landscape with Progressive Growth", "summary": "A new arXiv preprint (2608.24568v1) proves that progressive grow-and-optimize training biases deep neural networks toward flatter loss-landscape minima via a volume effect from frozen constraints, but finds in ResNet/CIFAR-100 experiments that flatter solutions do not always improve test performance. The study, whose code is on GitHub, models growth as progressive constraint relaxation and derives an explicit effective curvature for basin accessibility.", "body_md": "arXiv:2608.24568v1 Announce Type: new\nAbstract: Deep neural networks generalize well despite their highly nonconvex, overparameterized loss landscapes, a phenomenon often associated with the geometry of the minima found by stochastic optimization. We study how incremental grow-and-optimize strategies bias training toward flatter regions by viewing growth as progressive constraint relaxation. Starting from a low-dimensional submodel, we iteratively expand the trainable parameters by unlocking nested random subspaces while freezing the orthogonal complement at the network initialization, re-optimizing after each expansion until the full architecture is reached. Under standard local regularity conditions around non-degenerate minima, we prove that local sublevel sets are well approximated by ellipsoids and that basin accessibility under frozen constraints can be characterized by an explicit effective curvature in the frozen directions. This leads to an explanation of the bias: progressive growth increases the relative weight of wide basins and suppresses sharp ones through a volume effect induced by the frozen constraints. We empirically validate these predictions in controlled toy landscapes and in a realistic ResNet/CIFAR-100 setting and confirm that although progressive subspace growth reliably produces flatter solutions, curvature reductions do not universally translate into improved test performance, highlighting subtleties in the flatness-generalization connection. The code is available at https://github.com/p0lcAi/Across-the-Loss-Landscape.", "url": "https://wpnews.pro/news/across-the-loss-landscape-with-progressive-growth", "canonical_source": "https://www.machinebrief.com/news/across-the-loss-landscape-with-progressive-growth-hgq7", "published_at": "2026-08-26 04:00:00+00:00", "updated_at": "2026-08-26 09:44:30.103480+00:00", "lang": "en", "topics": ["machine-learning", "neural-networks", "ai-research"], "entities": ["arXiv", "ResNet", "CIFAR-100", "GitHub"], "alternates": {"html": "https://wpnews.pro/news/across-the-loss-landscape-with-progressive-growth", "markdown": "https://wpnews.pro/news/across-the-loss-landscape-with-progressive-growth.md", "text": "https://wpnews.pro/news/across-the-loss-landscape-with-progressive-growth.txt", "jsonld": "https://wpnews.pro/news/across-the-loss-landscape-with-progressive-growth.jsonld"}}