Wow. Really. There is even a dark matter particle. Note that the artist has not invested any prestige in preferring a particular hypothesis of the nature of this particle. Is it a neutralino?
Over at Cosmic Variance science blogger John Conway reports from the dark matter conference last week, and gives some more detail on the "nothing detected"result from CDMS I wrote about some days ago. John writes:
To “measure nothing” is usually a great experimental challenge. You do have to convince the world that you would have seen something if it had been there, that your apparatus isn’t just mute for some other reason.
Go read the rest! And see the graph displayed in his post, that shows the limit.
And when I'm at it, I can also link to the Bad Astronomer article, also about the CDMS result and about dark matter in general. Very accessible for a general reader.