[GraceG]

I think “Dark matter” is a fudge factor to describe a property of gravity that we haven’t figured out yet.

[cripplecreek]

Something that clearly exists because we can observe its effect but as you say it may just be an extension of a physical property we don’t understand yet.

[circlecity]

"I think “Dark matter” is a fudge factor to describe a property of gravity that we haven’t figured out yet."

Agreed. It is a term used to describe the fact that classic cosmological models don't conform to the observable data. (same with "dark energy")

[jjotto]

I think “Dark matter” is a fudge factor to describe a property of gravity that we haven’t figured out yet.

I suspect that as well. What's the grant money advantage of dark matter over incomplete understanding of gravity's normal characteristics?

[mikrofon]

Well, "fudge" *is* typically dark matter ....

[AFPhys]

Bubba: yes, "dark matter" can be used to account for some observations, but that is based on the assumption that G is solely based on r². In fact, the theoretical equations that describe gravity can also be solved with a dependence on r as well as r². Before the clear realization of the "expansion of the universe", most cosmologists assigned a value of zero to the coefficient for the r-term. Right now, it appears to me, that the simplest, "Occam's Razor" explanation of gravity, must include a very small, but NON-Zero coefficient for gravity's dependence on r. There are quite a few cosmologists now working to flesh out this concept. I have met a couple of them in Canada.

[MrB]

These kinds of fudge factors are usually hypothesized in order to make observations fit an assumed conclusion.

The Oort Cloud comes to mind as well.