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Re:The Universal Weight Subspace Hypothesis by daemonologist on Tuesday December 09, 2025 @01:44AM (#46201954)
I agree - the results on the finetunes are not very surprising. The trained-from-scratch ResNets (Figure 2 and Section 3.2.1) are definitely more interesting, though somewhat limited in scope.

In any case, my impression is that this is not immediately more useful than a LoRA (and is probably not intended to be), but is maybe an avenue for further research.

Re:The Universal Weight Subspace Hypothesis by augment_me on Tuesday December 09, 2025 @02:43AM (#46202316)
I don't think its that surprising actually. And I think the paper in general completely oversells the idea.

The ResNet results hold from scratch because strict local constraints (e.g., 3x3 convolutions) force the emergence of fundamental signal-processing features (Gabor/Laplacian filters) regardless of the dataset. The architecture itself enforces the subspace.

The Transformer/ViT results rely on fine-tunes because of permutation symmetry. If you trained two ViTs from scratch, "Attention Head 4" in Model A might be functionally identical to "Head 7" in Model B, but mathematically orthogonal.

Because the authors' method (SVD) lacks a neuron-alignment step, scratch-trained ViTs would not look aligned. They had to use pre-trained models to ensure the weights shared a coordinate system. Effectively, I think that they proved that CNNs converge due to it's arch, but for Transformers, they mostly just confirmed that fine-tuning doesn't drift far from the parent model.

Re:The Universal Weight Subspace Hypothesis by rhaps0dy on Tuesday December 09, 2025 @03:35AM (#46202634)
Thank you for saving me a skim
Re:The Universal Weight Subspace Hypothesis by swivelmaster on Tuesday December 09, 2025 @03:43AM (#46202691)
You’ve explained this in plain and simple language far more directly than the linked study. Score yet another point for the theory that academic papers are deliberately written to be obtuse to laypeople rather than striving for accessibility.
Re:The Universal Weight Subspace Hypothesis by bmacho on Tuesday December 09, 2025 @04:04AM (#46202848)
Vote for the Party that promises academic grants for people that write 1k character long forum posts for the laypeople instead of other experts of the field.
Re:The Universal Weight Subspace Hypothesis by swivelmaster on Tuesday December 09, 2025 @04:43AM (#46203102)
I’m not sure that’s something we get to vote on.
Re:The Universal Weight Subspace Hypothesis by eru on Tuesday December 09, 2025 @05:28AM (#46203389)
On the margin, you can let anything influence your voting decision.
Re:The Universal Weight Subspace Hypothesis by swivelmaster on Tuesday December 09, 2025 @02:57PM (#46209802)
File under "technically true but not particularly useful"
Re:The Universal Weight Subspace Hypothesis by eru on Wednesday December 10, 2025 @04:37AM (#46215830)
Well, it's not like voting is particularly useful in the first place.
Re:The Universal Weight Subspace Hypothesis by rocqua on Tuesday December 09, 2025 @04:57AM (#46203191)
I don't think the parent post is complaining that academics are writing proposals (e.g as opposed to people with common sense). Instead, it seems to me that he is complaining that academics are writing proposals and papers to impress funding committees and journal editors, and to some extend to increase their own clout among their peers. Instead of writing to communicate clearly and honestly to their peers, or occasionally to laymen.

And this critique is likely not aimed at academics so much as the systems and incentives of academia. This is partially on the parties managing grants (caring much more about impact and visibility than actually moving science forwards, which means everyone is scrounging for or lying about low hanging fruit). It is partially on those who set (or rather maintain) the culture at academic institutions of gathering clout by getting 'impactful' publications. And those who manage journals also share blame, by trying to defend their moat, very much hamming up "high impact", and aggressively rent-seeking.

Re:The Universal Weight Subspace Hypothesis by swivelmaster on Tuesday December 09, 2025 @12:08PM (#46207455)
Yes, thank you, exactly. It’s a culture and systems issue. Thank you for clarifying a post I wrote in the early morning while waiting for my baby to fall back to sleep!
Re:The Universal Weight Subspace Hypothesis by shoubidouwah on Tuesday December 09, 2025 @05:40AM (#46203441)
and hope for a president that can do both
Re:The Universal Weight Subspace Hypothesis by mapt on Tuesday December 09, 2025 @09:23AM (#46205207)
We have this already. It's called an abstract. Some do it better than others.

Perhaps we need to revisit the concept and have a narrow abstract and a lay abstract, given how niche science has become.

Re:The Universal Weight Subspace Hypothesis by mlpro on Tuesday December 09, 2025 @11:00AM (#46206419)
I think its very surprising, although I would like the paper to show more experiments (they already have a lot, i know).

The ViT models are never really trained from scratch - they are always finetuned as they require large amounts of data to converge nicely. The pretraining just provides a nice initialization. Why would one expect two ViT's finetuned on two different things - image and text classification end up in the same subspace as they show? I think this is groundbreaking.

I don't really agree with the drift far from the parent model idea. I think they drift pretty far in terms of their norms. Even the small LoRA adapters drift pretty far from the base model.