In the 1960s, the idea that some sort of anti-gravity would be possible in the future wasn't so silly. I don't think anti-gravity is a silly idea. We're only

In the 1960s, the idea that some sort of anti-gravity would be possible in the future wasn't so silly. I don't think anti-gravity is a silly idea. We're only starting to learn about the quantum world, and who knows what we will discover beyond that?