A LITERAL BRAIN BOX

Our brains are thought to be made of around 100 billion neurons, while the biggest computer chips top out at tens of billions of transistors. Meanwhile, each neuron can be connected to as many as 10,000 others, making for up to 1,000 trillion synaptic connections. By some metrics, the human brain is equivalent to a 1 trillion bit-persecond computer. Add to that the fact that the brain’s peak power consumption is around 20 watts, and that makes the brain 10,000 times more efficient than the best integrated circuits.

Hold that thought while we consider another. Thanks to the increasingly power-hungry nature of computer chips, plus the rising cost of energy, it’s more expensive to run a server for a few years than to buy it. Both in terms of increasing compute density and making it affordable to use, a big increase in efficiency would go a long way. The advanced micro-integration group at IBM’s research lab in Zurich thinks the brain has the answer – or rather, the brain’s fractally branching network of blood vessels makes for a very interesting model.

IBM is working on in-chip microfluidic channels that supply power and enable cooling. The idea functions like a flow battery, in which power is provided by two liquids that produce electricity when meeting on either side of a membrane. If the idea works, it’ll be useful for 3D chips with multiple layers of integrated circuits.