08 January 2007

Datk matter map of the universe

This 3D map of the dark matter in the Universe has been all over the prers today and very impressive it is too.

Apparently dark matter neither reflects nor emits light and it makes up the bulk of the mass of the universe. It is all very fascinating but I do have a big problem - I just can't get my head around this even though I have watched every episode of every incarnation fo Star Trek! If anyone can suggest a simple book with short words and lots of pictures I would be very grateful!


Bryan said...

No one actually knows what dark matter is. The only reason we know it exists is by inference. Matter has gravity and gravity bends light. There has to be matter in the highlighted areas of the graphics because light gets bent, but we can't detect it directly.

Think of a power cord. You know there could be electricity running through that cord, but you can't see the electricity, you only see the effect.

We have developed instruments to detect and measure electricity, but we still don't have the instruments to directly detect and study dark matter.

mullet said...

so bryan...scientists are bored?

the dark matter thing is interesting...but it's all theory just now

jams o donnell said...

Indeed Bryan, what particularly mystifies me is the discussion of the various particles that Dark Matter may be made up of - Axions, WIMPs etc.. Physics was never my strongest subject...

Agreed it is a theory. It could well be that scientists have this totally wrong. On the other hand they probably have a largely if not totally correct idea of what Dark Matter is.

Bryan said...

One of the weirdest aspects of dark matter is that the particles can apparently pass through each other without interacting. Based on what observations there are, and those are extremely limited, dark matter particles don't seem to collide with each other.

I tend to think that much of this is simply a result of our lack of tools. Once we develop the instruments to actually observe dark matter, I think many of the assumptions will have to be scrapped, as occurred in particle physics when we started to develop the tools to really "look" at subatomic particles.

jams o donnell said...

I think you are right there. If dark matter can be observed and studies it will probably turn some disciplines on their heads.

I will admit though that physics is one of my blind spots (along with calculus and anything more complex in maths)... I doubt things will change hugely there!