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Tour quiz · Is time travel possible?

What stuck?

Optional: 7 questions, one from each stop — a few minutes. Trying to remember is what makes it stick, so guess before you look back.

1 · Clock Lab

Why does a moving light clock tick more slowly?

2 · The 1 g voyage

How can a crew reach the galaxy's centre in about 20 years of their own time?

3 · Spacetime

Two lamps flash at the same moment for you. For someone moving past, they…

4 · River

In the river picture, what makes the horizon a point of no return?

5 · Wormholes

Why can't anything travel through the Einstein–Rosen bridge?

6 · Time loops

How does Gödel's universe allow a trip into your own past?

7 · Concept · time travel

Which kind of time travel has actually been measured?

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