How does the Higgs mechanism give mass to particles?
The mechanism is rooted in spontaneous symmetry breaking. Imagine a perfectly symmetric system, like a pencil balanced on its tip—it is symmetric but unstable. When it falls, it chooses a direction, breaking the symmetry. In quantum field theory, the Higgs field has a potential that is symmetric but has a nonzero minimum. The field settles into this minimum, breaking the symmetry and acquiring a nonzero value everywhere in space. Particles like the W and Z bosons interact with this field, and their interaction energy manifests as mass. For fermions, the mechanism is slightly different: they gain mass through Yukawa couplings to the Higgs field. This is not just a mathematical trick; it reveals something deep about nature—that mass is not an intrinsic property but a consequence of the universe's broken symmetry.
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