/sci/ - Science & Math

Does anyone know about a good book that details human migration? Such as why people decided to leave their continent and venture into the ocean?

I assume people first used boats to travel local distances in which they knew where point B was, then as they found more and more point Bs they could estimate areas to create a map for sailing (using many tools), and this took small steps to lead people to a better understanding of their land/ocean.

But I wondered if there was some evidence that showed that some people may have just took a boat and ventured into the unknown, and actually made it to safety, with their incentive being 'how to get more land or food'. I'm not referring to Magellan or more modern travelers, I mean the very very very ancient people (say, assume the out of Africa theory holds true, then why and how did people leave?)

Continuing from >>3496191

The red lines on this picture are geodesics. Pretend this is the spacetime diagram, time on the vertical axis and position on the horizontal. You can see that the two objects accelerate toward each other.

Draw the same diagram on a flat piece of paper - you just get two parallel lines that extend off to infinity.