Your concern is at the heart of the effort to redefine the kilo. Everyone wants to link it to fundamental constants. The trouble is that the IPK is still more reliable than our measurements of Planck's constant and Avogadro's number.
The meter was an artifact until measurements of the speed of light surpassed the prototype. The situation here is the same.
If the world ended and all of the distributed artifacts were lost, you could use existing measurements of fundamental constants to redefine the kilo at slightly worse precision.
The meter was an artifact until measurements of the speed of light surpassed the prototype. The situation here is the same.
If the world ended and all of the distributed artifacts were lost, you could use existing measurements of fundamental constants to redefine the kilo at slightly worse precision.