> Tell someone in the 1600s about the concept of cellphones and they would say it’s impossible to ever instantaneously communicate with someone around the world

> Tell someone in the 1600s about the concept of cellphones and they would say it’s impossible to ever instantaneously communicate with someone around the world. I don't know that they would. In the 1600s, they'd just invented the printing press, so communication was already undergoing a fairly massive change. A book that once took a lifetime to copy could now be printed in three days. From there, it's a short walk to "this book that used to take a lifetime to copy can now be printed more or less instantly." And from there, we can start laying the groundwork for what we would eventually call telecommunications. Cell phones rely on technology that people in the 1600s hadn't discovered yet. Interstellar travel would require us to not only discover new technologies, but technologies that actively violate what seem to be pretty hard physical laws. If the speed of light really is a universal maximum, and something like an Alcubierre warp drive isn't possible, leaving this solar system is vanishingly unlikely.