Dark matter is really strange, but we do not know its composition, texture, weight, or any of its characteristics. What we do know is that there is a lot of dark matter, even more than usual matter, so it could be light or photon particles.
Is Space Entirely Dark?
We can think that it should be, but New Horizons discovered something very strange. There has been excess light from digicam noise, scattered daylight, extra off-axis starlight, crystals from the spacecraft thrust, and different instrumental outcomes, all creating an extra amount of light.
However, these outcomes can be modeled, and their magnitudes and contributions can be quantified. Although they had been subtracted out, an incontrovertible excess remained.
Some of them have been observed in the Kuiper belt plane, but the only observations that were made outside of the plane were used. Some of them were detected in the dusty region of the Milky Way, so this observation was also removed.
However, excess remains. What’s causing this? There were six theoretical contributions that were considered:
1) stars and galaxies that we can identify.
2) Unidentified stars and galaxies emit weak lights.
3) weak light that has been scattered by clouds (“Cirrus”),
4) scattered sunlight remaining on any dust outside the Solar System chamber,
5) additional light inside the camera.
6) Any weak cosmic optical background that is unrelated to the unidentified source.
After a lot of data, the scientists concluded that the light produced in the universe is twice as much as expected, more than the density of stars and galaxies combined. There is some sort of “cosmic optical background” where we are able to see more light than we are able to see.
There should be some source of this light in the universe.
Read: Dark Matter: How James Webb Telescope Will Answer This Cosmic Mystery?
Can this light be the extra gravity needed in our universe?
Well, the answer is a big fat “NO.”
There are two reasons for this:
First, the total power of this light is negligible. It is only tens of nanowatts per square meter of area. It is the sum of all forms of energy that contribute to the curvature of space-time, and the ragged form of this energy (i.e., non-zero rest mass) leads to the effect of space-time local gravity.
The total proportion of energy encoded in all light in the universe should be about 0.01% of the critical energy density, while the total proportion of dark matter should be about 27% of the critical energy density. Even 2, 10, or 100 times wrong is no longer close enough to explain dark matter.
Second, this reason is probably much more persuasive. Only objects with a non-zero rest mass can behave like dark matter, and light has no mass, as far as we know. In fact, without mass, it wouldn’t move at the speed of light, and we have serious limitations in this scenario.
A surprising observation occurred in 2017. On August 17, 2017, the Fermi Gamma Ray Burst Monitor detected the localized arrangement of high-energy photons, typical of gamma-ray bursts. Gamma-ray bursts come in two forms.
Among other things, there are short (less than 2 seconds) explosions, thought to be caused by neutron star mergers, and long (more than 2 seconds) explosions, thought to be caused by the collapse of the nucleus.
A huge, fast-spinning star. It’s exciting to see short bursts of gamma rays, but it won’t revolutionize the scientific world. Just a few seconds ago, gravitational wave detectors LIGO and Virgo also detected a sky-localized gravitational wave signal in exactly the same place.
The signal could only be observed for about 10 seconds, but with all the properties of the Last Breath and the possibility of the merging of two massive, dense objects. The signal ended abruptly at a point corresponding to the merger itself, later determined by the merger of two neutron stars about 130 million light-years away. And only 1.7 seconds later, the gamma rays reached the Fermi detector at the same time.
The Reason Photons Can’t Be Dark Matter
Hypothesizing an event that occurred when two large and compact astrophysical objects merged at a particular time. These gravitational waves travel at the speed of light through the universe, covering a distance of about 130 million light-years.
(For such close objects, ignoring the expansion of the Universe is acceptable; excluding it results in a distance/travel time error of less than 1%). , which also travels through the Universe, traveling a distance of 130 million light years before arriving at our detector.
The two signals, emitted almost simultaneously (within two seconds of each other), traveled through space for 130 million years (about 4 1015 seconds) and reached their final destination two seconds apart from each other.
They ran one-on-one races that were almost ultramarathons, moving at the same speed with better accuracy than parts per trillion. In other words, if a photon has mass, its mass must be so small that it does not show a noticeable difference in the distance traveled by a rushing photon and a rushing gravitational wave over a time interval of 100,000,000 years or more!
In fact, there is enough evidence to impose an equally stringent upper limit on the mass of photons along with the magnetohydrodynamic effects of the solar wind, giving the strictest limit that the rest mass of the solar wind must be less than or equal to 10-18 eV/c2.
That makes it one billionth billionth of the mass of a proton. If the photon has a rest mass, this rest mass must be absolutely negligible.
This removes photons from being a candidate for Dark Matter.
If something has a mass, it should behave similarly to a matter
Yes, if a photon has mass and has so little kinetic energy that it actually hits a galaxy or cluster of galaxies, it will help to increase the rest of the mass of that structure. It does not emit light on its own under gravity. It will function like dark matter.
How much energy is there in the universe?
In the case of longer waves, low-energy photons may have much more energy than the maximum allowable mass they could Have Also, if you want the photons to be at the speed of light, you would have to increase the wavelength up to 1 billion kilometers, which is approximately the distance between the Sun and Jupiter.
This is a massive problem as the dark matter is not already falling into a huge mass that already exists in the universe. There is a major reason for reducing the initial formation of a huge lump, and there is a main reason we can see the same shape. This means that dark matter must have moved non-relatively from the very beginning, slower than the speed of light. This is why you can sometimes distinguish between hot, warm, and cold dark matter. The universe is very interested in how fast dark matter always moves relative to the speed of light.
According to the observation, for a matter to be 100 degrees Celsius cold, it must move slower than the speed of light, even though the universe was hotter, denser, and more energetic than it is now.
The universe is actually filled with hot dark matter substances like neutrinos that are made up of a giant number of photons in the early stages of the ultimate big explosion.
Neutrinos are a factor of 7000 that exceeds the maximum mass that can have at least a photon, and until the universe is hundreds of millions of years old, they should not move slowly against the speed of light.
Photons with the lowest energy will still move quickly against the speed of light. Even if they had mass and they actually acted as dark matter, we could not explain the dark substance we actually have in the universe. Their astrophysical effects cannot adequately explain observations of galaxies, clusters of galaxies, cosmic nets, and the imperfections we observe in the cosmic microwave background.
Does Dark Matter Have Something Else?
The only possible photon is in principle that the only way we can actually fall into the dark substance owned by the universe is to make it almost explode on everything.
There is a candidate that has a dark matter that is actually the richest mass, and it is provided with a mechanism for the axis,it is the axion.
Despite the fact that photons do not follow these rules, theorists have devised a very clever modification of possible rules, and they were able to use additional mechanisms to make birth of these more significant as a very low energy event.
Related particle types known as dark photons can potentially become a few candidates for dark matter. But the rules we know are acts like radiation, not any type of question as described by Feynman’s Maxwell and the electrical mechanics of bilateral electrical dynamics.