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5/5 A symmetric partner to all the known particles could provide the key to understanding them
4/5 The most common particle in the universe continuously passes through each of us.
3/5 Every particle has an antiparticle. Should the two combine, the result is annihilation.
2/5 Quarks comprise virtually all visible material, but why do we know so little about them?
1/5 Simon Singh on the significance of five subatomic particles, starting with the electron.