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Comment by powera | Hacker News Reader

"As a result, gravity, which is a pushover on everyday scales, catches up with the other forces and becomes their equal at a sub-sub-subatomic distance known as the Planck scale (around a few trillionths of a trillionth of a trillionth of a meter)."

What? How is that not completely wrong? Gravity is at its most important on large scales. Or are they just badly describing a (known-to-be-broken) quantum gravity model?

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If you compare the strength of the gravitational attraction between the proton and electron in a Hydrogen atom to electro magnetic force, then gravity is negligible. Or as my physics teacher once put it, while picking up a book: "There is an entire planet pulling on the book, but I win."

So yes, Gravity is the most important force, but that is a consequence of the existence of positive and negative charges, not of the strength of gravity.

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

Gravity is the force that acts on large scales because the other forces aren't present. That doesn't make it strong. It's easy to appear strong compared to nothing.

Yes it must be wrong, and that's what the whole article is about.

We know that gravity can't be so important on small scales because the universe would fall apart if that would be the case. However, our current theories of physics do tell us that gravity is that important on small scales. So the interesting conclusion is that something must be missing in our current model of quantum physics.

I think they may referring to the relative strength of the forces at "everyday"--i.e., human--scales.

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