UC Santa Cruz

The human brain and modern computers are both extremely efficient computational machines, executing large amounts of operations at incredibly fast speeds. Such performance costs energy, with the theoretical minimum being Landauer’s limit. We attempt to investigate and compare the efficiency of computation between our brain and the modern computer, i.e. cost of energy per bit of information. Every machine, including our brain, specialize in certain types of computation. We are more adept at survival tasks such as spotting colors versus mathematical operators, which the modern computer is so efficient at. Therefore, we will avoid the algorithm and architecture aspect of these computational machines. We instead quantify what a bit of information is and estimate the energy cost in both machines. We find that modern computers are extremely efficient, requiring approximately 10-19 J/bit which is only 103 away from the Landaeur’s limit while our brain requires 10-18 J/bit. Despite the lack of precision, the disparity is great enough to establish that modern computers are more efficient at executing a bit of computation.