AbstractModern Science-Fiction often assumes future “discoveries” in theoretical physics. Most of the stories would be impossible if our present understanding of the world of particles and forces stands firm. Since big modifications of what we found cannot be expected, one may wonder what humanity’s future might look like. Can outer space be colonized? Can intelligent robots be built? Can we travel to the stars? Can we control the Earth’s climate? Lecturer speculates on what can be done, not on what will be done.