Researchers found the universe's missing material.

"An artist's impression of the Milky Way's hydrogen halo, with the Magellanic Clouds at eight o'clock. (NASA/CXC/M.Weiss; NASA/CXC/Ohio State/A. Gupta et al) (ScienceAlert, Half The Universe's Matter Was Missing. Astronomers Just Found It.)

"A new analysis of the sky has finally confirmed where the missing half of the Universe's visible matter has been hiding." (ScienceAlert, Half The Universe's Matter Was Missing. Astronomers Just Found It.)

"In the space around galaxies, it lurks as huge, invisible clouds of ionized hydrogen. Normally, this would be impossible to see – but a large international team of astronomers and astrophysicists has developed a technique that reveals its hiding places, out there in the darkness amidst the stars." (ScienceAlert, Half The Universe's Matter Was Missing. Astronomers Just Found It.)

The galaxy's hydrogen halo can be far bigger than the galaxy itself. There is lots of material in it. 

Half of the universe's material is somewhere, and now researchers found it. That matter is ionized hydrogen around galaxies. The ionized hydrogen around galaxies can be ionic. Or in some cases an anion type. As we know. That the hydrogen ion is a proton. That lost its electron. Radiation from galaxies can shoot electrons away from a proton's orbiter. 

There is also the possibility that radiation can push the proton and increase its energy level. That makes it possible that two (or maybe more)electrons can orbit the proton. The ion where atoms lose one or more electrons is a more common form than the anion. 

The matter around galaxies can hide because the shine of galaxies and quasars is so bright. The radiation that comes from galaxies and quasars reflects from those protons. In normal cases, the radiation reflects from the atom. That is far larger than a proton. 

When the particle receives radiation, its energy level rises until it turns higher than its environment. In that case, energy starts to flow away from the proton. The proton sends radiation in a wavelength that is the same as its size. Same way. Protonic radiation is the reflection radiation. Neutron radiation is radiation that comes or reflects from neutrons. In neutron bombs small hydrogen bomb sends radiation into neutrons. 

Then that radiation reflects out from the neutron. That forms very shortwave and penetrating radiation. The same thing happens to protons that receive radiation from galaxies. Proton takes radiation into its quantum field. When the proton's energy level rises higher level than incoming radiation it sends that radiation as a reflection. 

It's possible that. In some cases radiation. That the proton reflects can travel past the particle. In some very extreme models the weakly interacting massive particle, WIMP is so small particle. Or its shape is so different that radiation slides over it without affecting its quantum field. Or maybe the quantum field that surrounds the WIMP will not send so strong reflection that astronomers can separate the reflection from the background. 

The proton sends radiation whose wavelength is shorter than the hydrogen. This makes that reflection radiation harder to see than the reflection that comes from hydrogen. 

When we think about the black hole's interactions between material the material that is locked to the point of the event horizon transports energy out from the black hole. When a black hole's spin accelerates it pulls energy inside it. The black hole ties energy from around it and then transforms it into kinetic energy. 

When a black hole's spin speed decreases that means the black hole releases its energy. The black hole's spin speed cannot change. 

If it cannot release or bind energy inside it. When a black hole releases its energy. That slows its speed. 

There is also the possibility that sometimes a black hole that pulls material inside it loses its contact with quantum fields and its material disk. In that case, the black hole sends gravitational waves and probably Hawking radiation. In the real universe, some particles might have a higher energy state than others. 

https://www.sciencealert.com/half-the-universes-matter-was-missing-astronomers-just-found-it