do neutrons have more effects than neutrinos? it turns out-- i should say, a beam of neutrons, you would have more hits with a neutron than with a neutrino, but not too many more. you could walk through a neutron beam without harm, but i guess the counter reading over here would be a little less for neutrons, but with neutrinos, you get the whole class standing here. hey, let me tell you what it is. it's a piece of lead, if you get a piece of lead, thick enough, then it will stop half the neutrinos. how thick you suppose is that gonna be about, this thick? this thick? this thick? this thick? as thick as the building? as thick as the world? as thick as like the diameter of the solar system? several light-years thick? and guess what the answer is, gang. six light years. eight solid light years. if you get eight years thick of lead, that's how far the sun will go in eight years, light will go in eight years. get that thickness. now put a beam of neutrinos through, half will come out the other side. so enormously, enormously transpar