Comment on "$Z_{2}$ spin liquid phase on the kagome lattice: a new   saddle point", by Tao Li [arXiv:1601.02165 (2016)]
  In a recent paper [arXiv:1601.02165], Tao Li claimed that a gapped $\mathbb{Z}_2$ spin liquid, obtained using projected Gutzwiller fermionic wave functions, can be stabilized in the Heisenberg model on the kagome lattice. We perform very accurate variational calculations and confirm with unprecedented accuracy the fact, that the $\mathbb{Z}_{2}$ spin liquid is a local energy minimum that goes away with system size, thus reaffirming the scenario of a gapless $U(1)$ Dirac spin liquid ground state. 
Yasir Iqbal, Didier Poilblanc and Federico Becca
cond-mat.str-el