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A charged particle can outrun light in water, not in a vacuum

Charged particles can move through water faster than light travels through that water, producing Cherenkov radiation. They are not outrunning light in a vacuum, so the glow does not break relativity's speed limit.

3–5 min

Questions you could explore

  • Why is light’s speed through water different from its speed in a vacuum?
  • How does Cherenkov radiation differ from light emitted because a material is simply hot?

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A charged particle can outrun light in water, not in a vacuum | Speech Topic | speaking.app