Here on Mi Yodeya we have a long and extensive (and growing!) list of sci-fi and fantasy questions.
Have there been any Rabbanim who have written complete Sefarim on these kinds of topics?
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Sign up to join this communityHere on Mi Yodeya we have a long and extensive (and growing!) list of sci-fi and fantasy questions.
Have there been any Rabbanim who have written complete Sefarim on these kinds of topics?
A simple way to find such information would be to read the sources cited in the answers to those questions.
I cited here a section of the Sefer Moreh Ohr by Rabbi Aryeh Kaplan who wrote about the topic of aliens.
The entire essay appears on pp. 47-50 in Moreh Ohr. This is the end which I have translated:
We see from this [starting on p. 47] that there is a singular species in the world that is capable of free will, Torah, reward and punishment which are the purpose of creation. This is mankind, to whom God has given The One Torah. It is however possible that there exists many species of living creatures on other stars i.e. planets, which may even be capable of intelligence and wisdom, just not freewill. The subject of freewill is but a very small item as it is, that cannot be verified in science [or by scientists], only by belief in our Torah. And if they do find additional species of living creatures, we have already learned from the Torah that don't have freewill.