I was in a situation where I was watching a Simpson's movie. The plot was that Mr. Burns had survived into the future (perhaps through cryogenics or other life extension) and was surveying all the places he could go and conquer. Bored with the pedestrian options of living in the future, he had elected to time travel into the past.
The part of the movie I was watching had Mr. Burns wearing a futuristic suit, with his face made out of a solid white plastic. He was flying in a space ship toward past earth.
mr burns: "Yes, who knows what this parallel Earth we will be encountering will be like. Perhaps they evolved a little differently, they might have craniums like the cro-magnons. And we have technology from the future that is beyond their wildest comprehension. We have seen Bruce Willis movies they could not even fathom, like The Liquidator! They'll have no idea what hit them, Smithers!!!"
smithers: "Sir, we're at the coordinates where Earth should be... but there's no planet here."
mr burns: "No planet?! What do you mean?"
The scene switched and I could see that the planet was actually there, but this parallel Earth society had been tipped toward Mr. Burns arrival from the future. They had banded together and shifted Earth out of normal matter and into dark matter.
I find it interesting how the idea of protecting Earth may be a reason why alien communication is not possible. See also: Queen Eggs and Stanford
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