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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....

104,017 Aufrufe • vor 3 Monaten •via X (Twitter)

12 Kommentare

Profilbild von Rob Sneiderman
Rob Sneidermanvor 3 Monaten

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.

Profilbild von Sonny from Laguna
Sonny from Lagunavor 3 Monaten

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

Profilbild von Yagami
Yagamivor 3 Monaten

@grok Give me the gist of this article

Profilbild von JÜRGEN
JÜRGENvor 3 Monaten

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

Profilbild von Michael
Michaelvor 3 Monaten

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?

Profilbild von ᛕᎥᕼᗷᗴᖇᑎᗴ丅Ꭵᑕᔕ
ᛕᎥᕼᗷᗴᖇᑎᗴ丅Ꭵᑕᔕvor 3 Monaten

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:

Profilbild von Huysolo
Huysolovor 3 Monaten

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

Profilbild von michael
michaelvor 3 Monaten

Is this why metronomes fall into synchronicity after a period?

Profilbild von PeteSK
PeteSKvor 3 Monaten

Thanks for posting these I have them filed for watchin!

Profilbild von AFX LAB
AFX LABvor 3 Monaten

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.

Profilbild von ራስ ባሪያው Rass Bariaw
ራስ ባሪያው Rass Bariawvor 3 Monaten

🗝️

Profilbild von DanNoaHided
DanNoaHidedvor 3 Monaten

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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