1. What gives matter mass?

2. Mass is a measure of how much matter there is in an object Matter is made of fundamental particles which have a range of very particular masses, but why? And what about photons, which don’t have any mass? In other words, what gives stuff stuff? [CERN]

3. You would think there would be an answer to this, but it’s actually a mystery ?

4. You can tell something has mass because it resists changes in its motion – that’s Newton’s 1st law of motion Mass also gives things weight, the force that acts on anything in a gravitational field Einstein noticed that you can’t tell the difference between these two effects But that still doesn’t explain what actually causes mass http://commons.wikimedia.org/wiki/ Image:Albert_Einstein_1947.jpg

5. Physicists have a theoretical model that accounts for all the fundamental particles that matter is made from And the forces that act between them (except gravity, which is another story) The theory predicts the existence of a particle that has the job of giving other particles their mass It’s called the Higgs boson, after the Scottish scientist Peter Higgs who proposed its existence over 40 years ago…and scientists are still looking for it! [CERN]

6. Here’s the idea: –The universe is full of an invisible field called the Higgs field –When matter moves, the field “drags” on it – a bit like a celebrity being slowed down by loads of photographers –Particles with bigger mass are affected more than ones with little mass, or to put it another way a particle’s mass is determined by how strongly it interacts with the Higgs field –The “dragging” is caused by Higgs bosons [CERN]

7. If the Higgs exists, the LHC experiments should find it We know the range of possible masses for the Higgs, around 200 times the mass of a proton The LHC is the first accelerator that can collide protons with enough energy to create particles this heavy If we don’t find it, it’s back to the drawing board… [CERN]