No, they have some equations that match the observed data extremely well, up to interplanetary scale, and are the basis for a lot of technology that we use dail

No, they have some equations that match the observed data extremely well, up to interplanetary scale, and are the basis for a lot of technology that we use daily. Now there are some discrepancies between what we expect and what we measure at galactic scale. A very popular hypothesis is that these discrepancies are due to some dark material that we haven’t been able to observe otherwise.