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October 21, 2026

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Zhihu Hot List via UAPI · saved Oct 21, 2026, 3:09 AM CST

There is no bijection from R³ to R², so how can a two-dimensional foil be created?

Background: A two-dimensional foil is a fictional weapon in Liu Cixin’s The Three-Body Problem that reduces three-dimensional space to two dimensions.

Read original on Zhihu Hot List via UAPI ↗ · Daily record · Monthly report