OT: Another dark matter candidate

You pointed out that some of the random noise on your microphone output was Johnson noise in the amplifier. Best of luck with quantifying your predictions accurately enough to tease out a third mechanism of noise generation.

John Larkin only mentioned Brownian motion because he didn't have clue how particle hunters actually worked, back in the day when there were more particles around to find. Look up the Wilson cloud chamber.

You seem to have wandered off the point by invoking other causes of noise which are likely to be below the threshold of detection. Your original statement "But we don't hear Brownian motion. It's just random noise." did not make sense to me when you wrote it and it still doesn't make sense. to me now.

What we hear is random noise. Some of it may be generated by Brownian motion, but you can't tell which bit that might be.

What I originally posted was a reaction to John Larkin's

"If heavy gravitons exist, wouldn't we hear them? Like brownian motion. It would be noisy."

to which I responded

"But we don't hear Brownian motion. It's just random noise."

If you had processed John Larkin's half-witted proposition you might have understood my response to it.

One heavy graviton per 21.5 metre cube of space isn't actually going to be noisy. We don't know what one might do if it showed up in the atmosphere at sea level. The point about dark matter is that it doesn't interact with normal matter by any mechanism other than gravitational attraction and a nanogram of mass isn't going to produce much of a tidal effect.

The fact that this particular basic particle would have one electron/proton's worth of charge might mess that up a bit, but we wouldn't see the basic particle but some kind of bizarre diatomic molecule with a dipole moment, and dipole fields a decay with the fourth (on axis) to the sixth power (off axis) of distance.

Anyway finding one would take more than listening for it, as was made clear in the original article, which seemed to think that some of the exotic particle detectors which we've sticking down mines for years now might be reconfigured to detect their particular exotic particle.

When I went back to start of the thread and read the link again

Their detection is discussed in some detail

"Among all detectors, the Chinese Jiangmen Underground Neutrino Observatory (JUNO) now under construction, seems predestined for such a search. It aims to determine the properties of neutrinos (actually antineutrinos) but since neutrinos interact extremely weakly with matter the detectors must have very large volumes. In the case of the JUNO detector, this means 20,000 tons of an organic, synthetic oil-like liquid, commonly used in chemical industry, with special additions, in a spherical vessel with a diameter of approximately 40 meters with more than 17 thousand photomultipliers around the sphere. JUNO is scheduled to begin measurements in the second half of 2025."

"The recently published paper in Physical Review Research by Meissner and Nicolai, with collaborators Adrianna Kruk and Michal Lesiuk from the Faculty of Chemistry at the University of Warsaw, presents a detailed analysis of the specific signatures that events caused by gravitinos could produce at JUNO and in future liquid argon detectors such as the Deep Underground Neutrino Experiment (DUNE) in the United States."

I suspect that the 2/3 charge gravitino's would couple up as weird massive diatomic molecule in low temperature environments - anywhere outside a star - and the 1/3 charge gravitio's would couple up with each other in the same way.

Whether the dipole moments of the pairs would offer enough interaction with normal matter to let them be detected strikes me as something that might need to be looked into.

There was a very good chemist at Nijmegen when I was there who went off to Germany to become a director at a Max Planck Institute for chemistry in Berlin and - rumour has it - was setting a sort of cyclotron for neutral molecules relying on their dipole moments for coupling to the accelerating field. A few years later he came back to Nijmegen University as the vice-chancellor so it may not have worked out. I wasn't working for the science faculty by then, so I'd lost my access to that kind of gossip.

There's also the thought that the two 2/3 charge positively and negatively charged gravitino's might be each other's anti-particles which would mutually annihilate if they got close enough.

At least the six 1/3 charge gravitinos could pair up with non-identical partners. A three way coupling of two 1/3 charge gravitinos and one