Brainstorming: Incorporate Dark Matter in a campaign

[Anders]

So I learned on Twitter that they've found a galaxy made up almost entirely of dark matter. That made me think about dark matter and how to incorporate it into a gaming world. Presumably IN SPACE, although I could easily see it in a horror campaign as well.

So what would you do with Dark Matter in a campaign setting? I'm thinking of having it as a kind of "dimensional shadow" of a parallel universe. We can see the gravity here, but no other forms of radiation. And somewhere there is a portal... and something wants to open it.

[Anthony]

Realistic dark matter seems to be almost totally uninteresting (it's basically a diffuse cloud of stuff that doesn't interact with much, including itself) except as it indicates we're missing something in our physics (it can't be made up of any of the particles in the standard model).

Cinematic dark matter could include stuff like alternate universes that only interact through gravity.

[Flyndaran]

Dark Matter not interacting with itself, outside of gravity, just means multiple shadow universes. ;)

And I'm suddenly reminded of The Large Hadron Rap. https://www.youtube.com/watch?v=j50ZssEojtM

[Dalillama]

The Schlock Mercenary comic features dark matter entities that want to destroy our kind of life because we won't stop travelling in hyperspace.

[malloyd]

Originally Posted by Anthony

Realistic dark matter seems to be almost totally uninteresting (it's basically a diffuse cloud of stuff that doesn't interact with much, including itself).

Can you even say that much? After all on the scale we can see it's effects we model stars as more or less a diffuse cloud, and yet matter does some interesting stuff at smaller scales.

What you can say about dark matter is quite limited - it produces a lot of gravitational attraction, it's apparent mass is distributed differently than the stars, and anything else it does is currently invisible to us. Anything beyond that is guesswork.

[Anders]

Originally Posted by malloyd

Can you even say that much? After all on the scale we can see it's effects we model stars as more or less a diffuse cloud, and yet matter does some interesting stuff at smaller scales.

Our best physics leaves out dark matter entirely and is still fantastically accurate, so it's not having a great influence on normal matter. But yes, there are models of dark matter coming in several different variants.

[Anthony]

Originally Posted by malloyd

Can you even say that much?

Whether or not dark matter collides with itself affects its distribution, and thus indirectly affects galaxy formation; my understanding is that it has to not significantly collide with itself or the large scale structure of the universe would be different.

[Lord Azagthoth]

What about the theory that Dark matters keep the galaxies compact?

Some stars should have left their galactic orbit with their current speed and trajectory but still, they stay in orbit. They think it might be the Dark Matter that is keeping the galaxies from falling apart.

[Flyndaran]

Gravity holds things together. Gravity is a facet of matter, and dark matter is still matter. I'm not sure what you're saying isn't just a tautology.

[David Johnston2]

Originally Posted by Anders

So I learned on Twitter that they've found a galaxy made up almost entirely of dark matter. That made me think about dark matter and how to incorporate it into a gaming world. Presumably IN SPACE, although I could easily see it in a horror campaign as well.

So what would you do with Dark Matter in a campaign setting? I'm thinking of having it as a kind of "dimensional shadow" of a parallel universe. We can see the gravity here, but no other forms of radiation. And somewhere there is a portal... and something wants to open it.

I use it as a buzzword to justify pseudo-reactionless drive.