There are theoretical designs using antimatter (pion rockets, or beam core engines) that could reach 0.4c - 0.7c, which puts Alpha Centauri at decades away, not

There are theoretical designs using antimatter (pion rockets, or beam core engines) that could reach 0.4c - 0.7c, which puts Alpha Centauri at decades away, not millennia. https://arxiv.org/pdf/1205.2281 https://arxiv.org/pdf/1205.2281 https://ntrs.nasa.gov/api/citations/20200001904/downloads/20200001904.pdf https://ntrs.nasa.gov/api/citations/20200001904/downloads/20...