Relativistic geodesy article
The Independent web site has an interesting article on relativistic geodesy titles:
“Gravity measured for first time using a portable ‘atomic clock’”
The article on which the article was based is available in full here:
“Religion is a culture of faith; science is a culture of doubt.”
― Richard Feynman
That would be a great tool for NGS if they can take it another order of magnitude.
As I read the article, they are saying that if they rebuilt their equipment using the very best techniques they have identified to control every variation, they think they could achieve 10 cm elevation uncertainty.