[BurningFrog]

The name isn't great. It sounds like matter that doesn't produce light, when it's really "matter" that's invisible.

But not matter you can touch. Which makes it not really matter in normal English. You probably can't see it either.

So "Invisible Untouchable Gravitation Sources" would be a more descriptive name. I don't think it'll catch on.

[bdamm]

Perhaps it could be some form of friction we don't yet understand? I mean a form of gravitational friction?

The nice part of being an armchair physicist is spouting off nonsense - I suppose if I really wanted to find out, I could make up a mathematical model of my theory and then find out if the evidence fits. Sadly, I really have no idea how to do that!

[themartorana]

Ditto. Out of curiosity, is dark matter spread unevenly throughout the universe, or is it directly inverse to matter?

Like, when we expect dark matter causes an effect, is it because we expect there to be a massive dark-matter "object" acting upon matter, or can we attribute it to denser dark matter as space between matter increases?

Edit: would viewing dark matter provide a negative image of the universe?

I'm asking mostly because I'm curious if there is dark matter, "light" matter, and empty space, or only one or the other? I love imagining this stuff, as if two different universes in a multiverse - ours and one we can't see - are acting upon each other and causing what we strive to explain. As if they were passing through each other.

[smeyer]

No, dark matter is definitely not the inverse of regular matter. Dark matter is spread unevenly through the universe, and it's spread in a pretty similar (but still notably different) way to the spread of regular matter. For example, where you have galaxies with lots of regular matter there is also lots of dark matter, but it has a slightly different distribution. You seem to be imagining something cool, but not something that bears much resemblance to our universe.

[themartorana]

Thanks for that! I realize it was a pretty n00b question, I appreciate you taking the time. :)

[bdamm]

So there could be dark matter stars, and dark matter planets? Dark-matter supernovas? Perhaps even in the same locations? Or is this strictly a galaxy-scale phenomenon and not an immediately local phenomenon?

[socceroos]

That's part of the problem with dark matter theory, isn't it? Theory predicts even and well distributed dark matter anti-particles, yet there isn't in the observable universe...

[smeyer]

I'm not sure what you're referring to. I don't think the theoretical problems around antimatter are any worse for dark matter than they are for baryonic matter.

[Ygg2]

A more interesting interpretation would be that the observable universe could be near a parallel unobservable universe and that gravity of that universe is influencing current universe.

[rootbear]

I agree that dark matter isn't the best name. We could call it ether...