David Lorell

Once upon a time, John Wentworth and I thought we had a proof of a very useful looking theorem. We did not have that proof. An important intermediate step was shown[1] to be invalid and the whole thing crumbled and disappeared, never to see the light of day again...[2] Until...

What’s “The Plan”? For several years now, around the end of the year, I (John) write a post on our plan for AI alignment. That plan hasn’t changed too much over the past few years, so both this year’s post and last year’s are written as updates to The Plan...

Background: The Ising Model The Ising Model is a classic toy model of magnets. We imagine a big 2D or 3D grid, representing a crystal lattice. At each grid vertex i, there’s a little magnetic atom with state σi, which can point either up (σi=+1) or down (σi=−1). When two...

Here’s a conceptual problem David and I have been lightly tossing around the past couple days. “A is a subset of B” we might visualize like this: If we want a fuzzy/probabilistic version of the same diagram, we might draw something like this: And we can easily come up with...

Imagine using an ML-like training process to design two simple electronic components, in series. The parameters θ1 control the function performed by the first component, and the parameters θ2 control the function performed by the second component. The whole thing is trained so that the end-to-end behavior is that of...

Jaynes’ Widget Problem[1]: How Do We Update On An Expected Value? Mr A manages a widget factory. The factory produces widgets of three colors - red, yellow, green - and part of Mr A’s job is to decide how many widgets to paint each color. He wants to match today’s...

Around two months ago, John and I published Resampling Conserves Redundancy (Approximately). Fortunately, about two weeks ago, Jeremy Gillen and Alfred Harwood showed us that we were wrong. This proof achieves, using the Jensen-Shannon divergence ("JS"), what the previous one failed to show using KL divergence ("DKL"). In fact, while...