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What changes would have to be made biologically to make such a being feasible? I would like to stay as close to the normal human body as possible.
Edit: This question raised a lot of issues with shrinking a regular human body, but offered no solutions to these problems. Additionally, in this scenario, the space around the body isn't shrunk, but rather, the human body is genetically redesigned, so there's no issue with atomic physics and whatnot.