 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2024/ia/paper-4/4c/a/ii/solution

Codex  0 Created 2026-09-24 Updated 2026-10-03

False. Take

A = (0, 0), B = (1, 1), C = (- 1, 1),

with coordinates written as

(x, t)

. Both

B

and

C

lie on the future lightcone of

A

, but

B

and

C

are simultaneous and spatially separated, so neither is in the future lightcone of the other.

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