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A Princeton probabilist explains why enormous random matrices stop behaving randomly and start behaving like a single fixed object. Almost nobody watches it. This is Ramon van Handel at Harvard's Science Center, April 2025, on the strong convergence phenomenon. Every weight matrix in every model starts as random numbers....

103,685 просмотров • 1 месяц назад •via X (Twitter)

Комментарии: 12

Фото профиля Rob Sneiderman
Rob Sneiderman1 месяц назад

A visual companion for the first step in this story: the thin-shell phenomenon. As dimension grows, a Gaussian vector still has random coordinates, but its normalized length becomes sharply concentrated near 1. Randomness remains locally; globally, the geometry becomes predictable. That concentration-of-measure viewpoint is one of the cleanest entry points into high-dimensional probability.

Фото профиля Sonny from Laguna
Sonny from Laguna1 месяц назад

It’s almost like there’s some kind of law of large numbers at play…

Фото профиля Yagami
Yagami1 месяц назад

@grok Give me the gist of this article

Фото профиля JÜRGEN
JÜRGEN1 месяц назад

Great you said almost nobody watches it. which means you've employed reverse psychology which means I definitely can't watch it now. thanks.

Фото профиля Michael
Michael1 месяц назад

wait this is literally just how statistics works, same thing with atoms determinism is non-determism at scale is this something thats not taught to ml students?

Фото профиля ᛕᎥᕼᗷᗴᖇᑎᗴ丅Ꭵᑕᔕ
ᛕᎥᕼᗷᗴᖇᑎᗴ丅Ꭵᑕᔕ1 месяц назад

Gerald Weinberg did say something similar in 1975 in his "An Introduction to General #Systems_Thinking." Many have a problem in realizing this simple truth:

Фото профиля Huysolo
Huysolo1 месяц назад

Random at small scale. Deterministic at large. Nobody told the engineers.

Фото профиля michael
michael1 месяц назад

Is this why metronomes fall into synchronicity after a period?

Фото профиля PeteSK
PeteSK1 месяц назад

Thanks for posting these I have them filed for watchin!

Фото профиля AFX LAB
AFX LAB1 месяц назад

Traditionally, eigenvalues are diagnostic. We compute them to understand a system after the fact. But if they instead become active state variables that exert forces, then the optimizer isn't just following the landscape, its reshaping the landscape while it moves through it.

Фото профиля ራስ ባሪያው Rass Bariaw
ራስ ባሪያው Rass Bariaw1 месяц назад

🗝️

Фото профиля DanNoaHided
DanNoaHided1 месяц назад

I spoke to a PHD electrical engineer and when he told me I could count to more than 10 on both hands I was shocked!

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