Mass of everything
- dark matter is making up 90% of all the known universe, we calculate this because gravitational interactions of the universe show a much more massive universe than we can otherwise explain through observation. So dark matter has mass and interacts with/through gravity. That implies that here on Earth dark matter particles that have mass will interact with Earth's gravitational field and therefore have weight.
- dark matter is distributed around the whole universe, including, right here right now, myself having billions of WIMPS stream through me without touching (so, presumably, huge amounts of WIMPS would be constantly streaming through every earthly object)
...so does it follow that dark matter is contributing to the mass of every object and person etc in the world?
If dark matter is evenly distributed around the universe by volume, we would have already detected it because instead of atomic weights being neat multiples of each other (H, 2H, 3H etc with H being mass of Hydrogen), they would be (X+H, X+2H, X+3H etc with X being dark matter mass). If dark matter is randomly distributed AND has an effect on mass we would never be able to measure a consistent mass. If dark matter is distributed among other particles according to the other particles' masses, we would not have previously detected it as all masses would be scaled up proportionately (XH, X2H, X3H etc). This is also not possible because if that were the case, we would have factored in the dark matter mass in our 'observed mass' calculations, and never noticed there was any dark matter in the first place.
Since none of these possibilities seem remotely likely, the conclusion is that even if I have a million tons of dark matter particles whizzing through me, they have no effect on my mass / weight. But that would mean that dark matter has no detectable gravitic effect here on earth but we can still detect the aggregate dark matter mass through it's effects on gravity.
Whichever way I look at it, my mind is well and truly boggled.