Three Barriers to Interstellar Visits: Distance, Physics, and Earth's Biosphere
To the point
Kateryna Ivaniuk says interstellar visits are unlikely because three barriers—huge distances, insurmountable physics and energy needs with radiation hazards, and Earth's unique biosphere that may not be hospitable to outsiders—exist, and there have been no confirmed signals from intelligent civilizations after decades of SETI and Breakthrough Listen searches.
