Quantum Sensing for Gravity Cartography

https://www.nature.com/articles/s41586-021-04315-3

by bookofjoe • 4 years ago

19 10 4 years ago

nature.com

nynx2• 4 years ago

Wonder if we’ll be able to make something equivalent to a gravitational camera at some point.

pa7x1• 4 years ago

That's what LIGO is, in essence.

fmajid• 4 years ago

The French navy is going to equip 4 ships with ONERA's GIRAFE quantum interference gravimeters, starting in 2023, based on a prototype developed in 2012:

https://www.capital.fr/economie-politique/la-marine-francais...

One of the goals is to be resistant to GPS jammers.

arlort• 4 years ago

Maybe it's explained in the article but my french isn't great

But how would that work to replace (?) GPS?

petermcneeley2• 4 years ago

I did some simulations of doing this (in Qbasic). The issues that I ran into was that effectively the matrices were singular. I think this might not be mathematically possible for static gravity measurements.

nynx2• 4 years ago

Interesting! Perhaps that could’ve been a numerical accuracy issue? Do you have code somewhere you’d be willing to share?

jubjubbird• 4 years ago

Apologies for the paywall, but this paper describes imaging cargo containers with gravity gradient sensors (to look for, e.g., plutonium):

https://ieeexplore.ieee.org/document/4215058

Basically you can image anything if there is a density contrast, it's "just" a matter of how good your sensor and inversion algorithm is.

I spend my day-to-day working on measuring gravitational changes to determine groundwater storage change. There's a huge difference between demonstrating something in the lab vs. building an actual field instrument you can use in the real world.

Quantum Sensing for Gravity Cartography

Related Stories