Exploring the Possibility of Invisible Matter Existing in Different Dimensions

[Xyooj]

Invisible matter...

since the universe is made up of mostly invisible matter, are they in different dimensions that's why we can't detect them?

such as some say the deads live in the same world that the livings live, except in a different layer or dimension?

 

[mgb_phys]

since the universe is made up of mostly invisible matter, are they in different dimensions that's why we can't detect them?

No dark matter is just dark.
You can only see things if they reflect light (like planets) or light up themselves (like stars) a lot of the normal mass of the galaxy is dust, cool gas and low mass stars that we can't see because they are too faint.
In addition there may be other forms of dark matter that is made up of large number of sub-atomic particles.

We can detect the presence of this matter because it's mass has a gravitational effect on things we can see.