Noise in the brain enables us to make extraordinary leaps of imagination. It could transform the power of computers too [October, 2022]

>I became interested in how to construct a more accurate climate model without consuming more energy. And at the heart of this is an idea that sounds counterintuitive: by adding random numbers, or “noise”, to a climate model, we can actually make it more accurate in predicting the weather.

>Noise is usually seen as a nuisance – something to be minimised wherever possible. In telecommunications, we speak about trying to maximise the “signal-to-noise ratio” by boosting the signal or reducing the background noise as much as possible. However, in nonlinear systems, noise can be your friend and actually contribute to boosting a signal. (A nonlinear system is one whose output does not vary in direct proportion to the input.

>The brain has to process this data and somehow make sense of it. If it did this using the power of a supercomputer, that would be impressive enough. But it does it using one millionth of that power, about 20W instead of 20MW – what it takes to power a lightbulb.

>If the key to creativity is the synergy between noisy and deterministic thinking, what are some consequences of this?

>Just as a climate model with noise can produce types of weather that a model without noise can’t, so a brain with noise can produce ideas that a brain without noise can’t.

>the best-known advocate of the idea that computers will never understand as we do is Hawking’s old colleague, Roger Penrose. In making his claim, Penrose invokes an important “meta” theorem in mathematics known as Gödel’s theorem, which says there are mathematical truths that can’t be proven by deterministic algorithms.

>I have been arguing that we need computers to be noisy rather than entirely deterministic, “bit-reproducible” machines. And noise, especially if it comes from quantum mechanical processes, would break the assumptions of Gödel’s theorem: a noisy computer is not an algorithmic machine in the usual sense of the word.

>if we want the machine to be intelligent then it had better be capable of making mistakes.

>the type of synergistic interplay between noise and determinism – the kind that sorts the wheat from the chaff of random ideas – has hardly yet been developed in computer codes.

Interesting. Noise could act like a natural boundary condition that enables consciousness to establish what’s real and what’s contemplation.