The usual reply is that the universe is old and the galaxy isn't that big even at sub light speeds in geological time.
The dinosaurs became extinct 65 million years ago. The galaxy is 105,700 light years in diameter. If instead of dying the dinos spent five million years becoming sapient and building a 0.5 light speed engine, by now they could have traveled the galaxy edge to edge like three hundred times over.
my response to that is that 300 times is super tiny and unless alien life decided to travel 300 times (or even 600 times) in a mathematically efficient pattern to the edge of the galaxy (which they have no reason to because there's no reason to assume alien life would want to travel anyways, and it would be a massive waste of energy, resources, and people) we would never have even a hundredth of a percent of a chance of seeing them, even if they travelled 600 times in random directions.
Well, I just used 65 million as an example and Earth is 4.5 billion years old and there are much older planets. My point is that galaxy's size and age make factors other that possibility of FTL travel more important to the whole question. Factors like probability of multicellular, sapient life developing and sustaining itself long enough to colonize space.
The usual reply is that the universe is old and the galaxy isn't that big even at sub light speeds in geological time.
The dinosaurs became extinct 65 million years ago. The galaxy is 105,700 light years in diameter. If instead of dying the dinos spent five million years becoming sapient and building a 0.5 light speed engine, by now they could have traveled the galaxy edge to edge like three hundred times over.
my response to that is that 300 times is super tiny and unless alien life decided to travel 300 times (or even 600 times) in a mathematically efficient pattern to the edge of the galaxy (which they have no reason to because there's no reason to assume alien life would want to travel anyways, and it would be a massive waste of energy, resources, and people) we would never have even a hundredth of a percent of a chance of seeing them, even if they travelled 600 times in random directions.
Well, I just used 65 million as an example and Earth is 4.5 billion years old and there are much older planets. My point is that galaxy's size and age make factors other that possibility of FTL travel more important to the whole question. Factors like probability of multicellular, sapient life developing and sustaining itself long enough to colonize space.
deleted by creator