Could human be able to build cross outer-space empires in the future?

As in theory? It's possible. It's not going to be as vast as the Empire from Star Wars or the Federation from Star Trek, but with human colonies who have access to warp drive and communication that uses quantum teleportation as a means of transmission to communicate with the colonies, there could be dissidence between the worlds and someone could use this as a means to gain power in critical areas, especially military, and use it to rise like Hitler.

We have finished all Empires on Earth from 1945 & ending by 1991.

You are incapable of thinking beyond your medieval mindset of Empires & all that crap. Come out of it.

Well, who do you propose they conquer in this glorious empire? They haven't even found an amoeba outside the Earth.

Surprisingly enough, anonymous Internet strangers don't know any more about the future of human civilization than you do. If we survive as a civilization, that's what we'll do. If we don't, we won't.

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That is the next stage, we have made it to space,

It would probably take quite a few humans.