Ampere in the 2019 redefinition of the SI base units by
Ciro Santilli 32 Updated 2024-09-07 Created 1970-01-01
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TODO how does basing it on the elementary charge help at all? Can we count individual electrons going through a wire? www.nist.gov/si-redefinition/ampere/ampere-quantum-metrology-triangle by the NIST explains that is it basically due to the following two quantized solid-state physics phenomena/experiments that allows for extremely precise measurements of the elementary charge:
- quantum Hall effect, which has discrete resistances of type: for integer values of .
- Josephson effect, which provides the Josephson constant which equals: