On Looped Transformers as Programmable Computers

This seems to be an interesting approach!

"A recent paper from University of Wisconsin-Madison and Princeton demonstrates the expressive power of Transformers embedded in simple loops. They show that constant depth Looped Transformers are highly expressive and can be programmed to emulate a particular Turing Complete computer, fundamental linear algebra operations, and stochastic gradient descent on in-context data. ..."

From the abstract:
"We present a framework for using transformer networks as universal computers by programming them with specific weights and placing them in a loop. Our input sequence acts as a punchcard, consisting of instructions and memory for data read/writes. We demonstrate that a constant number of encoder layers can emulate basic computing blocks, including embedding edit operations, non-linear functions, function calls, program counters, and conditional branches. Using these building blocks, we emulate a small instruction-set computer. This allows us to map iterative algorithms to programs that can be executed by a looped, 13-layer transformer. We show how this transformer, instructed by its input, can emulate a basic calculator, a basic linear algebra library, and in-context learning algorithms that employ backpropagation. Our work highlights the versatility of the attention mechanism, and demonstrates that even shallow transformers can execute full-fledged, general-purpose programs."

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Looped Transformers as Programmable Computers