(May 8, 2009 at 9:20 am)g-mark Wrote: Why do they look for it then?
To explain why galaxies orbit faster than they should.
Either there is a large amount of mass there that emits no radiation (and hence we cannot observe), or our theory of gravity is wrong.
We have been discovering new particles as recently as 1995 (top quark) and our description of gravity works so well that we have such accurate satellite navigation, can derive the Earth's orbital period etc.
Therefore it seems reasonable to assume the former.
My issue was that you quoted that there are "billions of particles per second"
This is an absolutely baseless statement
Galileo was a man of science oppressed by the irrational and superstitious. Today, he is used by the irrational and superstitious who claim they are being oppressed by science - Mark Crislip
