Solved cryptogram
Light travels through a vacuum at a fixed speed, and that speed now defines the meter itself.
Physics Facts, sourced to NIST.
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What it means
For most of the nineteenth century a meter was a bar of metal kept near Paris, and every copy of it was slightly wrong. The definition now runs the other way around. The speed of light in a vacuum is fixed by agreement, and a meter is whatever distance light covers in a set fraction of a second. That makes the unit reproducible in any well equipped lab, and it also means no experiment will ever measure the speed of light more precisely, because the number is no longer something anyone measures.
The claim comes from NIST.
- SourceNIST
- CollectionPhysics Facts
- Difficultymedium
- Length75 letters, 20 unique
Nearby in the collection
The facts either side of this one.
About as hard as this one
Scored closest to it by the model behind our guide to solving cryptograms.