[astro-ph.IM] The number of Galactic civilizations does not determine whether they are in contact. Allowing civilizations to appear at different times separates listening, audibility, mutual-listening, and relay networks, with a […]
![Graphical Abstract -- [astro-ph.IM]](https://i0.wp.com/astrobiology.com/wp-content/uploads/2026/11/Spacetime.png?resize=1200%2C608&ssl=1)
[astro-ph.IM] The number of Galactic civilizations does not determine whether they are in contact. Allowing civilizations to appear at different times separates listening, audibility, mutual-listening, and relay networks, with a […]