Dark Matter.....

[ToraToraTora]

OK, it's generally accepted that 27% of the universe is dark matter, we know it has gravity, and we know it must be there to make the universe work, or at least explain the observations and measurements. Matter as we know it makes approx 5% of the universe. Many questions have been asked what it is and when asked the same I always say, beyond its gravity we simply have no clue thus we make up the name to make our equations work. So as it's Friday 3 points to discuss:
1) Do you think there is life in the Dark matter universe?
2) Do you think they would notice our 5% missing in the same way we have noticed their 27%?
3) Speculate as to the nature of dark matter.

[Zacs-Master]

Parallel universe as in one which exists ‘next’ to ours in the Steinhardt model.

[jim360]

Way beyond my pay grade, that one :P

https://arxiv.org/pdf/astro-ph/0404480.pdf

On the face of it this has more to say about Dark Energy than Dark Matter. That's about all I'm prepared to say I think. Then again, I primarily do Particle Physics and at the moment that's struggling, experimentally at least, to find a Dark matter candidate, so maybe we do have to allow for the possibility soon that it *is* separate from "our" universe after all.

[Zacs-Master]

Pan, what a cop out ;-)

[Old_Geezer]

"I just started to think that as dark matter to us is basically a name we give to stuff so our equations fit the observations"
Surely, until we actually find some, that's exactly what it is ? Someone has conjectured some form of matter that would explain it.

[ToraToraTora]

OG we just know it has gravity and we know how much of it there must be to hold galaxies together.

[Zacs-Master]

problem with that is, we don’t exactly know what gravity is.