Technology that could have existed

I don't think you can armor a zeppelin, even if you fill it with vacuum instead of gas...

I'm convinced Einstein would have finished his Equation of Everything had he not died when he did. From what I've heard, he was about halfway through with it WHEN he died, but that could just be a fairy tale.

I'm convinced Einstein would have finished his Equation of Everything had he not died when he did. From what I've heard, he was about halfway through with it WHEN he died, but that could just be a fairy tale.

I doubt it. The closest we currently have to that is string theory and that wasn't really even realized until the 80s.