In the past two weeks I read two papers from arXiv that present some very interesting new ideas. The first paper, Extended Møller-Plesset perturbation theory for dynamical and static correlations, by Takashi Tsuchimochi and Troy Van Voorhis, deals with symmetry restoration in second-order perturbation theory. The extended MP2 method presented by the authors looks promising and I found it very interesting because it can automatically adapt to single- and multireference problems. At the very end of the paper the authors even show that their technique can be used to compute excited states.
The second one,Compact wavefunctions from compressed imaginary time evolution, is from Jarrod R. McClean and Alán Aspuru-Guzik. This paper mixes compression techniques with a propagation of the Schrödinger equation in imaginary time to compute the ground state energy.