Could dark matter be photons that "ran out of steam?"?

Question

Even though it is said that photons have zero mass at rest, if there were a bunch of them resting about some place, surely they would have some kind of effect.

By the way, I presume that such a "photon" might take on another form and certainly would not be light (as we understand it).

Answer 1

no, by definition photons are only moving at the speed of light, because after all, photons are light.

and even if photons are resting, they do have zero mass... it's not like virtually zero mass, they really do have zero mass. As in, they have no mass at all, no matter how small. They're called massless particles.

don't worry about it, you won't really understand unless you've studied electromagnetism, relativity, particle physics or quantum mechanics.

btw, dark matter is just matter that doesn't give off light. we can see things such as stars, because they give off light. dark matter doesn't, and thus they are dark. the two leading theoretical dark matter objects are called MACHOs (MAssive Compact Halo Objects) which are brown dwarfs if i recall correctly, and WIMPs (weakly interacting massive particles) which are neutrinos, i just included this because i think they have cool names

and where dark matter came from, to counter jim's argument, is that we've observed some objects, such as, say, galaxies, which aren't merely models, which don't completely follow Newton's Universal Law of Gravity, or Einstein's General Relativity when that's factored in, unless there is some other mass out there which we can't see which is responsible for the perturbation of the orbits.

Answer 2

No, because of what you say - they have no mass. Dark matter is only known of because of its gravitational effect. Whatever it is, it has mass.

One guess is that neutrinos could be much of it. Every since they confirmed that neutrinos do have a mass, though very small, this has become a possibility.

Also, there is a problem with the idea of photons "running out of steam". Remember, at the speed of light time does not pass, so each photon has experienced 0 time since its creation. In 0 time it has not had time to run out of steam.

Answer 3

Technically no rest mass = no gravity right? So photons don't even have a gravitational pull.
Since we only know about dark matter through it's gravity, I highly doubt photons in any form are what make up dark matter.

Answer 4

well it is unknown what dark matter is since it is made of unknown compositions. Some particles that scientist speculate to make up dark matter is supersymmetry. Dark matter is for sure made of particles that don't emit anything that we can see and photons are light particles that we can see. Also dark matter is said to make up most of the matter in our universe and since photons at rest have zero mass then it is not possible that dark matter can be made up of photons.

Answer 5

that is misleading the moon is dark matter as it does not generate light but its not spent photons the term can be used to broadly as to say that any matter not making light is dark.planets asteroids ice chunks and any thing else not burning falls into that catagory. as matter has anti matter light may have anti light and that could be a compleatly different subject altogether

Answer 6

Dark matter could be anything or nothing. It is a result of using models that are not accurately saying how the real universe works. Its very poor science to get that dependant on models don't you think?

Answer 7

Dark matter are not protons but are area which do not reflect light.

More than this scientists are trying to decipher this with various theories which do not have proper backing.