4 ms·

The article links to a better article, https://news.sky.com/story/royal-navys-experimental-ship-carries-out-first-trial-of-quantum-navigation-system-12889487 ht

by wging 3y ago

The article links to a better article, https://news.sky.com/story/royal-navys-experimental-ship-carries-out-first-trial-of-quantum-navigation-system-12889487 https://news.sky.com/story/royal-navys-experimental-ship-car..., which calls the device an accelerometer. I think the article linked here got literally all its information from that other article. Apparently it's a small number of rubidium atoms, cooled to near-absolute zero, under which conditions they can apparently measure gravitational effects and make deductions from that ("measure extremely accurately the influence of gravity on their system, which in turn allows them to measure the speed and direction of its movement").

readyplayernull 3y ago
》measure gravitational effects and make deductions from that ("measure extremely accurately the influence of gravity on their system Aha! So it might be able to detect other submarines, even if they use some stealth tech.
- rz2k 3y ago
  That sounds absurd, but the $5 pressure sensor on my weather station could detect a volcanic explosion 5,000 miles away. Is there even a difference between a submarine and the surrounding water's gravitational fields when the sub has neutral buoyancy?
  - Out_of_Characte 3y ago
    There probaly would be, the displacement might be the same but the distribution of mass wouldn't. But I recon these instruments are only sensitive enough to measure the difference between the seafloor and the water above.
  - WinstonSmith84 3y ago
    I'd argue that the gravity field of a sub is not uniform despite having neutral buoyancy. No idea though how significant that is vs. how sensible the measurement is
    - andromeduck 3y ago
      You'd have better luck trying to measure a neutron with a bathroom scale.
- andromeduck 3y ago
  Submarines generally have neutral bouyancy while underway so there's not much density difference to discern.
- whimsicalism 3y ago
  Not even close.

by wging 3y ago

readyplayernull 3y ago

》measure gravitational effects and make deductions from that ("measure extremely accurately the influence of gravity on their system Aha! So it might be able to detect other submarines, even if they use some stealth tech.

rz2k 3y ago
That sounds absurd, but the $5 pressure sensor on my weather station could detect a volcanic explosion 5,000 miles away. Is there even a difference between a submarine and the surrounding water's gravitational fields when the sub has neutral buoyancy?
- Out_of_Characte 3y ago
  There probaly would be, the displacement might be the same but the distribution of mass wouldn't. But I recon these instruments are only sensitive enough to measure the difference between the seafloor and the water above.
- WinstonSmith84 3y ago
  I'd argue that the gravity field of a sub is not uniform despite having neutral buoyancy. No idea though how significant that is vs. how sensible the measurement is
  - andromeduck 3y ago
    You'd have better luck trying to measure a neutron with a bathroom scale.
andromeduck 3y ago
Submarines generally have neutral bouyancy while underway so there's not much density difference to discern.
whimsicalism 3y ago
Not even close.