Now, to get back on topic…
Since the OP asks about THEORIES, let me throw out the possibility that the Antichrist (assuming this a going to be a literal occurrence sometime in the future), will actually appear to be an extraterrestrial. A recent somewhat hokey TV show called “V” presented this very scenario but without the religious element. Imagine if a ship appeared from space and a seemingly advanced individual of apparently great wisdom–and clearly far more advanced than us technologically–appeared…would the world fall down and worship such a creature?
Given the cacophony of religions and cultures in the world now, what other scenario offers any possibility of evolving into a one-world religion or even a one-world government? I don’t think it is a coincidence that modern pop culture has been flooded with UFO mythology and that the idea of extraterrestrials is almost ingrained now within every culture in the world.
Curiously, the UFO craze seemed to start around 1947-1948…which just happens to be when Israel was re-founded in the Holy Land promised to Abraham.
Matthew 24
32 “Now learn this parable from the fig tree: When its branch has already become tender and puts forth leaves, you know that summer is near. 33 So you also, when you see all these things, know that it is near—at the doors! 34 Assuredly, I say to you, this generation will by no means pass away till all these things take place. 35 Heaven and earth will pass away, but My words will by no means pass away.