You seem to be making a supposition that the world is violent (first), and then that the cause of that violence is the increasing human population of the planet. In the first place, that assumption or supposition is generally incorrect. The world has never been as generally peaceful as it is now. However, things aren’t perfect, and there certainly is a level of violence – particularly in some parts of the world and in some particular ethnic, religious, racial and class conflicts, and certainly among individuals. I think that the reason that the world is becoming more peaceful even as the human population increases is because more and more reliance is being made upon capitalism as an economic system that “works” – to the extent that it generally does, and it’s certainly not perfect, either! – to support the populations of the planet.