The cosmic structure growth is suppressed, and nobody knows why.

   The cosmic structure growth is suppressed, and nobody knows why.

The question is about the effects of dark matter and dark energy. There is a theory that there are two dark matter types. Hot dark matter is a material. Whose energy level is higher than visible material. Cold dark matter is material whose energy level is lower than visible material. 

Which way does energy travel? In this image, we can think that hot dark matter is the thing that is marked "dark matter". When that hypothetical material's energy level decreases. It turns into visible materials or atoms. Finally, it turns into cold dark matter and when those particles collapse into a 2D form they will make a short-term pothole that fills, and when quantum fields impact that pothole. They send energy impulses, that we see as dark energy. 

So energy travels from hot dark matter through visible matter into cold dark matter. The cold dark matter would be material that has a 2-dimensional structure. And that makes the cold dark matter act like an energy vampire. Energy travels from visible material into cold dark matter.

Maybe cold dark matter is the basic energy level in space. Where our universe exists. That cold dark matter would be invisible because energy travels into that material. The reason, why there are no signs of that cold dark matter is that there are lots more cold dark matter than visible matter. 

But when energy impacts dark matter particles they send that energy into other dark matter particles. And that energy moves the dark matter could. That could be the dark energy. 

"The local geometry of the universe is determined by whether the density parameter Ω is greater than, less than, or equal to 1. From top to bottom: a spherical universe with Ω > 1, a hyperbolic universe with Ω < 1, and a flat universe with Ω = 1. These depictions of two-dimensional surfaces are merely easily visualizable analogs to the 3-dimensional structure of (local) space". (Wikipedia, Shape of the universe)

Geometric shape of the universe. 

The reason why we cannot see hot dark matter either is when that material sends the radiation that we can detect it has turned into Higgs boson and then through the chains into stable electrons. And after that when that electron (or any other elementary particle) loses its mass, it turns into cold dark matter. 

Cosmic microwave background

The place of the cold and hot dark matter can be successively after visible material. And in that model, visible material is at the top energy level. In that model energy also travels into the dark matter and because there are lots of more dark matter particles than visible matter, that means the energy that travels into the dark matter. And then, it starts to travel between those dark matter particles. 

Cosmic gamma-ray background 

When we are looking at cosmic micro, gamma, and X-ray backgrounds, we can conclude that gravitational background forms similar structures as some of the cosmic backgrounds. That means gravitational waves or gravitational radiation is not homogenous. That causes the induction conclusion that the universe cannot be purely spherical, hyperbolic, or even flat. 

Cosmic X-ray background. 

The universe's shape would be like a rag, where one corner turned up. In that model, the universe's shape is a combination of those geometrical shapes.  The question about the universe's shape is interesting because it should be a combination of all of those geometrical possibilities. 

Most researchers believe that the universe is flat. But there is a model. where the material that forms our universe is like a ball above that flat universe. If that model is real, energy travels from that ball into that universe or energy level below it. 

In that model, the universe or the 3D material is like a ball, that hovers above the material the energy level is under detectable level. And that material is mainly the cold dark matter. If the cold dark matter's energy level is lower than the visible material's minimum energy level. That means energy travels from visible 3D material to that 2D material, and our universe is like a ball, that hovers in space. 

https://scitechdaily.com/universe-defies-einsteins-predictions-cosmic-structure-growth-mysteriously-suppressed/

https://en.wikipedia.org/wiki/Dark_matter

https://en.wikipedia.org/wiki/Shape_of_the_universe

Cosmic background images Space com, ESA and NASA