For over a hundred years, the original kilogram made of a platinum-iridium alloy was the standard for all weights. It only lost this prominent position in 2019, when the metrological world agreed to relate all physical units to natural constants. The metrologists chose the Planck constant h rather than a fundamental particle mass as the decisive constant for the kilogram, thus linking the kilogram to quantum electrodynamics. In a recently published article in Physical Review Letters (PRL), two researchers from QuantumFrontiers show that mechanical units such as the kilogram could alternatively be realised via gravitational effects.
In their work, Claus Lämmerzahl from the University of Bremen and Sebastian Ulbricht from the Physikalisch-Technische Bundesanstalt point out interesting parallels between electromagnetism on the one hand and gravity on the other. The starting point for their considerations are certain mathematical similarities between Einstein's general theory of relativity and Maxwell's theory of electrodynamics. ‘The analogy found could be used to test the universal validity of quantum mechanics,’ says Sebastian Ulbricht. Translated with DeepL.com (free version)
The correlations that emerge here could also be of metrological interest in order to understand mechanical units such as the kilogram not only in quantum-electrical terms, but also to realise them on the basis of gravitational and inertial forces. ‘Because what the electromagnetic field is for charges, the gravitational field is for masses,’ says Claus Lämmerzahl.
Originalveröffentlichung:
Gravitational Metrological Triangle
Claus Lämmerzahl and Sebastian Ulbricht
Physical Review Letters, 133, 241402 (2024)
