The nature of Matter

Today I listened to a talk by a cosmologist. I sort of feel that I ought to listen to talks by cosmologists. It sets a good example to my colleagues, and it's the kind of thing that people in the street occasionally talk about. Now quite early on in his talk he puts on his slide which explains what the universe is made up of. And according to cosmologists it is made up to a large extent of dark matter (4% at the latest count).

I am by association a particle physicist. I don't actually know much at all about particle physics, but armed with a good book I can sort of bluff my way through. The best book around, the bible of particle physicists, is the particle data book. This book lists all particles ever found, from neutrons and protons through to tau leptons and rho mesons and much more besides. This all counts as normal matter: these particles somehow interact with light, or each other, and it is possible to prove that they were there.

Of course particle physicists don't believe they have found everything. They leave the door open for new particles, some of which they expect to find, and some which would be rather surprising. You may expect that particle physicists would spend much of their time looking for the other 96% of the universe. Well they don't. If you take a look at the aforementioned bible, you find the following notes about the state of the world of particle physics. There is a lot written about the known particles, which is fair enough. Lots of time and money is spent studying these particles, and lots of people find meson resonances rather interesting. Now take a look at the searches: These are the things which haven't been found yet, but which some people think might be found at some point in the future. And how much of these 100 pages of speculation is devoted to dark matter? A single page (WIMP's and Other Particle Searches). The missing 96% of the universe gets stuck in the speculation:other category. To add further insult note they even added a greengrocer's apostrophe to the poor old WIMP in their listing.

Particle physicists should really spend more time in fights, flame wars and funding battles with cosmologists. I imagine the exchange would go like this.

Cosmologist: Look , you've had 70 years of accelerating stuff, about 100 billion dollars to play with and you've found what makes up 4% of the universe. Give it up.

Particle Physicist: Well a fat lot of use you lot are. What should we be looking for, exactly? Dark stuff, right, good.

C: You know the branching ratios of the 1475 MeV resonance of the eta meson to 5 decimal places, but you haven't a clue what's holding the universe together.

PP: It is quite obvious that you screwed up either your measurements or calculations, and you stuck them back together by inventing matter which by its dark nature nobody can ever disprove. We'll just hang around measuring branching ratios of eta mesons until you get it sorted.

C: Fuck you
PP: Fuck you too.

etc etc.