[Robert]

This paragraph states that dark matter surrounds galaxies in a gigantic halo and is totally invisible. However, dark matter can be observed indirectly because it bends starlight, just like glass, hence can be located by the amount of optical distortion it creates.

By being invisible, does that mean we can see through dark matter, or we can not see it because it does not give off any detectable radiation. The "just like glass" comment implies that light goes through dark matter as if it were a medium of higher density, like glass or water, and bends light via refraction. Is that correct? Can light pass through dark matter?

Or is dark matter distorting light by warping space-time with its high gravitational force. Seems like this is the better explanation, but the passage is ambiguous. But if this is the explanation, seems like we would see dark matter blocking the light behind it, or maybe causing a gravitational lense.

Another idea, could dark matter be a ring of rocks similar to the rings of Saturn and Uranus? In that case, at what size and density would the rocks need to be to allow light to pass and yet act as a medium that refracts the passing light. On second thought, I don't think refraction would be possible using a non-uniform or aggregate medium.

Other thoughts?

[Guille]

In the case of black holes light definatelly cannot leave once entered the horizon. If it is free DM in space, I think it might be that light does not refract.

[Casey_deJong]

what if dark matter is actually Black matter?
the reason we cannot see it is because it absorbs the light and not reflects it?
and it could be an atmousphere that warps the light?

although it is more likely a dense EMF or gravity field which bends the light although we would be able to find an Magnetic field i am pretty sure so gravity is my final answer.

[mkirkpatrick]

The properties of dark matter,are I feel the same as they are for light matter
and that is,crystalised thought awaiting a stimulus to activate colaeced intent.
There is talk of maybe 11 dimensions,in the string theory,in,one of these there
maybe properties of light,and electricty,that at present we know nothing about.One of these properties of light,is I feel,the ability to flow in liquid form,
a river of light,which,will illumine all the hues of the known spectrum,plus about
28 other ones,that we will never see.It is said that where there is a will,there
is a way,and the way seems to be that we are the product of thought,as is
all the known,and unknwn universe,it was willed to be,and so it was,there seems
to be no gaps,no empty space,all is absolutly full,so the properties of dark
matter,seem to be latent thought?

kind regards.michael.

[undef00]

my guess:

dark matter just has to exist - its to resist - the known matter

same on earth - we need oxygen to burn (is that right? i never was good in chemistry - guille? i did like geography and biology but NOT history - i hated english but i just love it NOW)

that meaning: there must be always a certain amount of oxygen(+++?)/dark matter available to exist on a given room in space

if dark matter/oxygen(+++?) becomes by coincident(i personally don't believe in coincident)/pushing research to much compared to the known matter/fuel cells (is that the right expression?) then we somehow have experienced singularity on a more or less particle basis

results may surpass even the imagination of a baby fish below water surface on earth ...

robert: i'll come back a little later to the actual question:

Can light(or similar) pass through dark matter?

[undef00]

a fish in a glas(don't do this anywhere!!!!!!!!!)/the solar system/star clusters/galaxies/+++ are all capable of experiencieng more or less instantenous singularity we could further assume ... if you have a phantasy driven mind ...

[michellemfry]

The fact that dark matter exists at the halos of an object that is separated by other objects with an expanding space are significant. The accelerated expansion and the vicinity of the expansion(halos) are adjacent spaces.Could it be a universal barrier to expansion, or a reaction to expansion? It could be like the shore of an ocean of expansion is defined by dark matter, and dark matter is the beach.

[Guille]

Originally Posted by michellemfry

The fact that dark matter exists at the halos of an object that is separated by other objects with an expanding space are significant. The accelerated expansion and the vicinity of the expansion(halos) are adjacent spaces.Could it be a universal barrier to expansion, or a reaction to expansion? It could be like the shore of an ocean of expansion is defined by dark matter, and dark matter is the beach.

Maybe, I hadn't thought of that. And maybe when the universe reaches the maximum point of expansion, this expansion goes down to 0, and the universe is exactly half it's life, then the matter has been becoming anti.matter, and now they ar equal, and from then on there will be more anti-matter, until the universe contreacts completely when it will all be anti.matter in cntrast to the start, where it was all matter. Now, for this hypothesis to be true, how can matter be becoming anti-matter? and how is it that we haven't seen this?

[michellemfry]

From A Hole in the Universe: In 1964, physicists discovered that matter and antimatter are not always mirror images; in certain rare cases, a particle will transform into an antiparticle more often than vise versa. Today, several laboratories around the world have created "factories" designed to produce vast numbers of similar strangely acting particles.