If we ever detect life elsewhere, how will we go visit? This lecture
considers the challenges of interstellar travel and colonization. The
problem is one of basic physics (the enormous energy requirements of
star flight) coupled with the vast, irreducible distances between the
stars. I will describe various starship concepts that use reasonable
extrapolat ... Show More
Nov 2009
Lecture 42: The Fermi Paradox
So, Where is Everybody? Interstellar colonization, in principle, is an exponential growth process that would fill the galaxy in a few million years even with a very modest star flight capability. This is a small fraction of the lifetime of the Milky Way Galaxy, so the Galaxy shou ... Show More
44m 58s
<p>La durée de vie d'une étoile peut nous renseigner sur sa composition et sur l'existence éventuelle de la vie dans le cosmos. mais, en dehors du Soleil, il est assez difficile de déterminer l'âge d'une étoile.</p><br><p>L'importance de la masse</p><br><p>En évaluant, grâce à la ... Show More
