From Electrons to Starlight: Honest Physics for Interstellar Travel and a More Efficient Self-Replicating Probe

Can electrons, quantum tricks or antimatter carry us to the stars? This study tests those ideas with open calculations and published work, then asks what an efficient self-replicating (von Neumann) probe would need. Electrons make poor propellant: at the same voltage and power, xenon ions give about 490 times more thrust. Light speed is unreachable, and even a one-tonne probe at 10% of light speed carries 126 TWh of kinetic energy. Chemical, nuclear and ion rockets cannot reach that speed; fusion, antimatter and laser sails can on paper. The proposed probe, Kuzimu Seed, is a laser-launched seed of about 10 kg that brakes on magnetic and stellar-light sails, cruises on americium-241, and on arrival rebuilds itself from local rock using solar cells tuned to its new star. For a red dwarf like Proxima Centauri, silicon cells waste much of the light; a 0.6 eV cell could capture far more.