Chess Opening Theory/1. d4/1...d5/2. e4/2...c5
After dxc5 dxe4 (Nf6 seems better), Qxd8+ is possible, which looks stronger than it is, due to Kxd8. This is the earliest possible queen exchange. Black has lost the right to castle, but white's pawn on c5 is weaker that Black's e4-pawn. White is better, but I don't know how much.
After cxd5, Qxd5 (or Nf6) is possible, since Nc3 runs into Qxd4.