>>104709845There is and then there isn't. I reason it this way, so sorry for my personal blog in advanced.
One, you can't have someone go into the future, confront the Big Bad who sent you to the future in the first place, and then hop back to the past and slay the Big Bad before he sends you off into the future. You could IF this creates multiple timelines, but Samurai Jack treated it as linear. It's the Grandfather Paradox but directed at the future.
Two, time is not stationary. How did Ashi know where to send Jack? When to send Jack? Fifty years equals fifty years of the celestial bodies moving across the universe, of the Earth spinning around in space, etc. The Earth fifty years ago is not at the same place fifty years later.
Three, assuming there ARE multiple timelines, Jack doomed the future to a world with Aku and no sword. But seeing how Aku outright said, "Oh no!", that points to a linear timeline. Everything was effectively erased. No fifty years of characters, no future, no Ashi, no anything.
Four, Ashi should have disappeared right on the spot after the past Aku was defeated. If time took a while to catch up to her, Jack should have suddenly aged fifty years and became an old man upon being returned to his original point in time.
This is why time travel is a tricky plot mechanic to use: it's more complicated than what people give it credit for.
