Interstellar Contact: The Absolute Barriers of Physics, Biology, and Timing

To the point

Fundamental limits such as vast distances, the speed of light, exponential fuel costs, biology, and timing make interstellar contact and travel effectively impossible, with warp drives and wormholes remaining theoretical and energy-hungry, a view echoed by Feynman, Thorne, Dyson, Alcubierre, Sagan, and Tarter, while the same physics that blocks travel also preserves causality and the conditions that make life possible.