Eli5: If dark matter has always existed, how did gravity laws work in the first place?

Question

When they discovered F= gMM/R^2 how did that… work… in the first place? Shouldn’t that have failed? bcoz dark matter would throw off the calculation of what was observed or observable?

In: 1

Answer 1

Dark matter does not behave differently regarding gravity.

It just behave differently for everything else.

So it’s the same difference as 1kg of lead vs 1kg of feathers vs 1kg of dark matter… It’s all the same mass.

Also, since dark matter only interact via gravity, it usually doesn’t clump together at human scale, so it only has a significant impact at much higher scale (e.g., galactic scale and beyond)