Is Gravity Relative to Density Alone

[mAMBOkING]

I apologize if this comes off as a dumb question, but does anyone know if gravity is ABSOLUTELY simply dependent on density alone, regardless of the type of material itself, or does the type material also factor into it's gravity?

 

[Drakkith]

Density: The mass density or density of a material is defined as its mass per unit volume.

I would say yes. The materiel itself obviously can be different, which would have different densities, but its still mass per volume.

 

[D H]

I apologize if this comes off as a dumb question, but does anyone know if gravity is ABSOLUTELY simply dependent on density alone, regardless of the type of material itself, or does the type material also factor into it's gravity?

Mass, not density. That gravitation is independent of the type or composition of material is one of the principle assumptions of general relativity.

This assumption, if false, would completely dismantle general relativity. An untested core principle is a bad thing, so of course this assumption has become one of the most precisely tested and verified principles of all of physics.

 

[TurtleMeister]

Not a dumb question at all. It's a question I've thought about a lot. And even though the composition dependency of passive gravitational mass has been thoroughly tested, from Newtons pendulum experiments to STEP, the case for active gravitational mass has received very little attention. In fact, the one and only laboratory test to date is the Kreuzer experiment of 1968. It obtained a precision of 5x10^-5. Compare that to the better than 1x10^-11 precision for passive gravitational mass experiments. So this principle assumption of GR is not as well tested as most people think.