S P A C E & T I M E
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S P A C E - T I M E
Representation of the two inseparable notions of space and time.
A flop transition is an event which occurs within the spaces of Calabi-Yau, it is a tear of the space-time. A transition of flop is a "reversal" of a sphere inside one of these spaces. It is these "reversals" which cause these tears.