This is amazing - I posted this question 2 years ago and then forgot about it - and just found it in my bookmarks... I love that a simple question has generated 3 pages of good debate from clever people... Job done!
Thanks all for the replies.
Hi Clever People,
I've been watching an amazing program about dark matter, dark energy and dark flow. I thought there were questions that should have been asked, but then I'm a website designer - what do I know!
So... as an interested non-physicist, my apologies if this question is...