April 15, 2021 updates Posted on April 15, 2021 by Doug Loss Searching for interstellar quantum communications https://arxiv.org/abs/2104.06446 Three microlensing planets with no caustic-crossing features https://arxiv.org/abs/2104.06544 Significant interstellar object production by close stellar flybys https://arxiv.org/abs/2104.06845 Positive Energy Warp Drive from Hidden Geometric Structures https://arxiv.org/abs/2104.06488