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Comment by otikik | Hacker News Reader

A submarine itself is quite massive, and has big moving parts (e.g. the rotor). The crew has less mass, but it would be very close, and also in constant movement. Wouldn’t this interfere with those measurements? Would they need to stop the engine and play “frozen TikTok” while the measurement device is active?

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Surely the influence of some of these sources of noise can be modeled and filtered out. A University of Vienna currently conducts experiments to measure the gravitational force at very small sales, and they already have to do this with things like crowds moving about the city during rush hours.

Sources of Noise?!

Doesn't that mean that the gravitational field is an information storage and transmission medium; a signal channel?

Is it lossy?

Is there a routable signal path to block harassing calls?

Is it slower or cheaper than nonlocal entanglement; like quantum radar?

What is the minimum energy necessary to cause a propagating thresholdable-as-binary pertubation of a gravitational field?

It sure is a medium! One Denver (IIRC) gravitational experiment could measure the field distortion caused by 100,000 people and cars at a local sports arena. [citation needed]

Is there a butterfly effect -like minimum pertubation for gravitational wave propagation through matter or massful things, at least?

Is there something that's low-enough power to not EM-burn a brainstem in a crytographically-keyed medical device with key revocation?

Does a fishing lure bobber on the water produce gravitational waves as part of the n-body gravitational wave fluid field, and how separable are the source wave components with e.g. Quantum Fourier Transform/or and other methods?

Butterfly effect: https://en.wikipedia.org/wiki/Butterfly_effect

Chaos theory: https://en.wikipedia.org/wiki/Chaos_theory

Quantum chaos: https://en.wikipedia.org/wiki/Quantum_chaos

Superfluid Quantum Gravity:

Backscatter: https://en.wikipedia.org/wiki/Backscatter

Not a formal definition, but noise is simply the undesirable parts of the output of any information processing device, be it a sensor, an amplifier, or a transmission medium. But on Earth it's simply not practical as such. Gravitational waves observatories are used to detect events such as neutron star or black hole mergers that are otherwise unobservable, but they require an insane level of precision to be detected.

Are there yet any instruments better than LIGO at a lagrangian point outside Earth's atmosphere and the Van Allen radiation belt?

No, there’s nothing yet. I think you‘re thinking about (e)LISA btw.

Here is a link for that:

https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...

LISA: Laser Interferometer Space Antenna: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant... :

> LISA would be the first dedicated space-based gravitational-wave observatory. It aims to measure gravitational waves directly by using laser interferometry. The LISA concept has a constellation of three spacecraft arranged in an equilateral triangle with sides 2.5 million kilometres long, flying along an Earth-like heliocentric orbit. The distance between the satellites is precisely monitored to detect a passing gravitational wave.[2]

It also says the ESA LISA projected launch date is in year 2037.

Could 3 or 4 cubesats per cluster solve for space-based gravitational wave observation?

CubeSat: https://en.wikipedia.org/wiki/CubeSat

Li-Fi: https://en.wikipedia.org/wiki/Li-Fi

Could the gravitational wave sensors be mounted on Starlink or OneWeb ULEO Ultra Low Earth Orbit satellites with a 5 year lifecycle? (Also, how sealed and shielded do consumer radio telescopes like Unistellar's eVscope and eQuinox need to be to last a few years in microgravity? Maybe mando blackout noise.)

What is SOTA State of the Art in is it "matter-wave interferometry"?

/? matter-wave interferometry wikipedia: https://www.google.com/search?q=matter-wave+interferometry+w...

/? matter-wave interferometry: https://www.google.com/search?q=matter-wave+interferometry

Can low-cost lasers and Rdyberg atoms e.g. Rydberg Technology solve for [space-based] matter-wave interferometry?

/? from:me LIGO https://twitter.com/search?q=from%3A%40westurner%20ligo :

- "Massive Black Holes Shown to Act Like Quantum Particles" (2022) https://www.quantamagazine.org/massive-black-holes-shown-to-... :

> Physicists are using quantum math to understand what happens when black holes collide. In a surprise, they’ve shown that a single particle can describe a collision’s entire gravitational wave.

- GitHub topic: gravitational-waves: https://github.com/topics/gravitational-waves

Further notes regarding Superfluid Quantum Gravity (instead of dark energy): https://news.ycombinator.com/item?id=36258299

I think you may be engaged in circular reasoning, here. Noise, by definition, is what can’t be modeled. The idea would be to have some model of the signal produced by the submarine’s machinery, and use that to reduce the noise (increase SNR) to the point that this nav system becomes useful.

Of course we would always filter out noise completely if it was that easy to model. My point was that some components of that noise (for example the moving parts of the engines) can be modeled very accurately.

I think we’re saying the same thing?

Yes, indeed

> Wouldn’t this interfere with those measurements

Towed sensors and multiple passes over known calibration zones?

> big moving parts (e.g. the rotor)

The shaft and screw are confined to the end of the sub. A navigation instrument like this would not be in the engineroom.

It is still way closer to the instrument than the deep end of the sea, most of the time. Square of distance is a very potent thing.

I am reminded of this:

https://www.theguardian.com/science/2015/may/05/microwave-ov...

Imagine spending 17 years to find the source of interference, and it's just Kyle with his chicken tenders.

Mount it on a UUV?

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