200
‘It’s the perfect place’: London Underground hosts tests for ‘quantum compass’ that could replace GPS
(www.theguardian.com)
This is a most excellent place for technology news and articles.
The article describes the device working in ways that violate relativity, but the actual technical description is a lot cooler.
It's not a quantum compass, really. It's a quantum accelerometer and gyroscope. The hope is that its accuracy will lend itself to long-term inertial guidance, which normally needs regular GPS updates to correct errors which accumulate over time.
ice what you did there
this is exactly what I got from the article: a more accurate inertial navigation. What part violates relativity?
You can’t use it to determine both your location and velocity at the same time. (/s)