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Summary
This is part one of a series of figures designed to help explain how a black hole distorts the causal structure of the space time around it. The figures are essentially cartoonized versions of Finkelstein diagrams (see: Hawking, Stephen W.; George Ellis (1973) The large scale structure of space-time, Cambridge: Cambridge University Press, p. 152ISBN: 0-521-09906-4. OCLC: 16002677. ). The diagrams have been stripped of their technical details as to emphasize the essence of the argument.
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Changes: the black hole is not a circle, but a straight area – this is a graphical representation of time. Also added a very light grid that represents spacetime.