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What gives matter mass?. 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].
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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]
You would think there would be an answer to this, but it’s actually a mystery ?
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
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]
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]
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]