I don't think it's possible to keep the whole earth alive.

The whole human civilization continues to this day because of the energy of the sun. Even if the huge energy burst by destroying the sun can be avoided, the source of human energy has become a huge problem. So the bunker plan is not reliable.

On the whole, the black domain plan is very ideal, which can preserve the integrity of the whole earth, but theoretically, first, it is very difficult to form a black domain, not to mention such a large black domain; Secondly, in the black domain, we simply don't know whether humans and the earth can adapt to such an environment and continue to survive. And there is a question, after the formation of the black domain, can the black domain still get energy from the sun? After all, light speed is not light speed.

Finally, the light speed spacecraft project. Thirty-six plans, walking is the best policy. It is impossible for all mankind to go. Just like the mythical Noah's Ark, even if it is really realized, the destination is unknown, leaving traces of flying at the speed of light and threats everywhere. Perhaps the more advanced civilization thinks that such a small scale does not pose a threat, and if it is not attacked, the survival probability of the light speed spacecraft in the universe is still very low, and it needs enough luck and adaptability.

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