In general, minimising a problem with the universal electron-correlation functional is known to in NP due to this [1]. Which is kind of sad for density function

In general, minimising a problem with the universal electron-correlation functional is known to in NP due to this [1]. Which is kind of sad for density functional theory (DFT). I've probably misphrased that. Also, side remark: Coding up a 2D Ising model solver with Metropolis-Hastings is surprisingly fun. Doubly so if you GPU accelerate it. [1] http://www.nature.com/nphys/journal/v5/n10/abs/nphys1370.html http://www.nature.com/nphys/journal/v5/n10/abs/nphys1370.htm...