[yendu bwam]

Second, if there are intelligent aliens, why aren't they here?

Quite possibly for the same reason that we aren't spread out all over the galaxy ourselves. The speed of light limit, and the enormous energies or time needed to traverse the galaxy put an enormous barrier to its exploration. Those barriers may be untranscendable, making them as difficult for others as they are for us.

[A.J.Armitage]

Quite possibly for the same reason that we aren't spread out all over the galaxy ourselves.

They all devoloped rocketry within the last hundred years?

[Boiler Plate]

Quite possibly for the same reason that we aren't spread out all over the galaxy ourselves. The speed of light limit, and the enormous energies or time needed to traverse the galaxy put an enormous barrier to its exploration. Those barriers may be untranscendable, making them as difficult for others as they are for us.

Maybe the didn't eat the apple and are still living in Eden. Why bother leaving if it can't get any better?

[FreeLibertarian]

Quite possibly for the same reason that we aren't spread out all over the galaxy ourselves. The speed of light limit, and the enormous energies or time needed to traverse the galaxy put an enormous barrier to its exploration. Those barriers may be untranscendable, making them as difficult for others as they are for us.

Understanding and harnessing Zero Point energy and the related physics will overcome those limitations.