The Universal Weight Subspace Hypothesis
2025/12/04 by Prakhar Kaushik, Kaushik, Prakhar, Shravan Chaudhari +7 · 20 voices · 4 citations
Computer Science · #Advanced Neural Network Applications #Adversarial Robustness in Machine Learning #Domain Adaptation and Few-Shot Learning
paper · pdf · doi:10.48550/arxiv.2512.05117
Abstract
We show that deep neural networks trained across diverse tasks exhibit remarkably similar low-dimensional parametric subspaces. We provide the first large-scale empirical evidence that demonstrates that neural networks systematically converge to shared spectral subspaces regardless of initialization, task, or domain. Through mode-wise spectral analysis of over 1100 models - including 500 Mistral-7B LoRAs, 500 Vision Transformers, and 50 LLaMA-8B models - we identify universal subspaces capturing majority variance in just a few principal directions. By applying spectral decomposition techniques to the weight matrices of various architectures trained on a wide range of tasks and datasets, we identify sparse, joint subspaces that are consistently exploited, within shared architectures across diverse tasks and datasets. Our findings offer new insights into the intrinsic organization of information within deep networks and raise important questions about the possibility of discovering these universal subspaces without the need for extensive data and computational resources. Furthermore, this inherent structure has significant implications for model reusability, multi-task learning, model merging, and the development of training and inference-efficient algorithms, potentially reducing the carbon footprint of large-scale neural models.
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- The universal weight subspace hypothesis [hn, 358 points, 132 comments]
- what if all AI models share a hidden, low-dimensional "brain"? The analysis of 1,100+ models (Mistral, ViT, LLaMA) shows they all use a few key "spectral directions" to store information. This univers [bsky, 7 points, 1 comments]
- The language of the abstract is straight out of Ghostbusters, but if I'm reading this right, it says that almost all LLMs converge on a common core structure for modeling human language and the images [bsky, 2 points, 2 comments]
- The universal weight subspace hypothesis View Article | Join the HN Conversation Summary of HN discussion 🧵👇 #hacker-news [bsky, 1 points, 1 comments]
- The Universal Weight Subspace Hypothesis [hn, 1 points, 1 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 https://news.ycombinator.com/item?id=46199623 [bsky, 0 points, 0 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 arxiv.org [bsky, 0 points, 0 comments]
- The Universal Weight Subspace Hypothesis https://arxiv.org/abs/2512.05117 [bsky, 0 points, 0 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 [comments] [260 points] [bsky, 0 points, 0 comments]
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- The Universal Weight Subspace Hypothesis arxiv.org/abs/2512.05117 [bsky, 0 points, 0 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 (http://news.ycombinator.com/item?id=46199623) [bsky, 0 points, 0 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 (http://news.ycombinator.com/item?id=46199623) [bsky, 0 points, 0 comments]
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- The universal weight subspace hypothesis https:// arxiv.org/abs/2512.05117 # arxiv [mastodon, 0 points, 0 comments]
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- The Universal Weight Subspace Hypothesis https://arxiv.org/abs/2512.05117 (https://news.ycombinator.com/item?id=46199623) [bsky, 0 points, 0 comments]
- The universal weight subspace hypothesis https://arxiv.org/abs/2512.05117 (https://news.ycombinator.com/item?id=46199623) [bsky, 0 points, 0 comments]
- The Universal Weight Subspace Hypothesis https://arxiv.org/abs/2512.05117 (https://news.ycombinator.com/item?id=46199623) [bsky, 0 points, 0 comments]
- The Universal Weight Subspace Hypothesis #HackerNews https://arxiv.org/abs/2512.05117 [bsky, 0 points, 0 comments]
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