“Laptops are very hot now, so hot that they are not ‘lap’ tops anymore,” says Avik Ghosh, a UVA assistant professor of engineering. He’s referring to the intense heat generated by computers, a byproduct of ever-increasing processing speeds. Unfortunately, that heat has to go somewhere—in this case, into your lap.
“The prediction is that if we continue at our current pace of miniaturization, these devices will be as hot as the sun in 10 or 20 years,” Ghosh adds.
To head off this problem, Ghosh and fellow UVA engineering professor Mircea Stan are re-examining no less than the Second Law of Thermodynamics. The law states that, left to itself, heat will transfer from a hotter unit to a cooler one—in this case between electrical computer components—until both have roughly the same temperature, a state known as thermal equilibrium.
The possibility of breaking this law will require the researchers to solve a scientifically controversial theory called Maxwell’s Demon. According to this theory, the energy flow from hot to cold could be disrupted if there were a way to control the transfer of energy between the two units. One component could take the heat while the other worked at a lower temperature, but such a scenario could only be accomplished if the degree of natural disorder, or entropy, were reduced. Such is the “demon” in Maxwell’s Demon.
“Device engineering is typically based on operating near thermal equilibrium,” Ghosh says. But, he adds, there are examples in nature of biological cells that operate outside thermal equilibrium. “Chlorophyll, for example, can convert photons into energy in highly efficient ways that seem to violate traditional thermodynamic expectations,” he says.
Ghosh and Stan also are re-examining a closely related concept, Brownian “ratchets,” which proposes that devices could be engineered to convert nonequilibrium electrical activity into directed motion, allowing energy to be harvested from a heat source.
If computers could be made with components that operate outside thermal equilibrium, it could mean better computer performance. Laptops wouldn’t scald their operators as they process larger amounts of information at faster speeds. Also, they could operate at extremely low power levels and have the ability to harness power dissipated by other functions—increasing battery life.