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Measurement

A kilogram defined by a constant, and instruments that make phenomena

Kibble · the metrologists · LIGO · 3 chapters · 8 min read

A kilogram defined by a constant, a number with a range, and instruments that make phenomena.

Free to read: every chapter below is open

Getting a Number

  1. 01The Kilogram Stopped Being an ObjectOn the day the kilogram stopped being an object in a vault.
  2. 02Every Number Has a RangeOn why a million careful readings can give a very precise wrong answer.
  3. 03Instruments Make PhenomenaOn why a reading is only as good as the theory behind the device.