
Experiment finds that gravity still works down to 50 micrometers - sohkamyung
https://arstechnica.com/science/2020/04/gravitys-inverse-square-law-tested-at-scale-of-a-human-hair-and-passes/
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magicalhippo
Previous discussion:
[https://news.ycombinator.com/item?id=22797729](https://news.ycombinator.com/item?id=22797729)

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gus_massa
Notre that it includes comments written by one of the members of the research
group, that is one of the regular here.

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pjc50
Good, but on the atomic scale that's still a lot - as I understand it the key
questions are how well it works on scales where the "strong" and "weak" forces
also apply.

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munkiefish
Does it matter though? If it will always be overwhelmed by the weak and strong
force as distances narrow (except near/in a black hole or if extra dimensions
actually exist)?

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adrianN
When energies are sufficiently high gravity can't be ignored anymore.

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cellular
On very small scale the force would be very very high as the denominator, d^2,
goes to zero. What limits the denominator going to zero? Could a close
distance really be what leads to the strong or weak force?

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bryanrasmussen
Is the "Next: find old wardrobe." supposed to be a Narnia reference? If not I
can't figure out what it is for.

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roessland
Yup. Narnia is a "hidden dimension". A bit of a stretch to compare Narnia with
spatial dimensions though.

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luxuryballs
If we find a small enough situation where gravity stops working I wonder if
there will be an inverse square law observed as they approach that level of
tiny. Like half way between the size where gravity works fullest and the
tinier size where it doesn’t work anymore is 75% less gravity.

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downerending
Was I foolish in thinking that gravity works at all scales?

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yrro
As a layman, no. "Our Ignorance About Gravity" at
<[https://www.youtube.com/watch?v=OTMELHUAzSM>](https://www.youtube.com/watch?v=OTMELHUAzSM>)
explains what we don't know about gravity at small and large scales.

