What the Dirac equation predicted — relativistic quantum mechanics requires antimatter to exist

Why the Dirac equation has negative energy solutions — interpreted as positrons, confirmed by Anderson in 1932

Dirac equation predicts negative energy states, later identified as antiparticles, positrons, by Anderson's experiments

What CP violation means — charge-parity symmetry is broken in weak interactions, explaining matter-antimatter asymmetry

CP violation allows for matter dominance over antimatter in the universe

What the EPR paradox challenged — Einstein argued entanglement implied either hidden variables or nonlocality

EPR paradox questioned quantum mechanics' lack of locality and determinism

What Fermi-Dirac statistics describe — the distribution of fermions, which obey the exclusion principle

Fermi-Dirac statistics describe the distribution of particles like electrons, obeying the Pauli exclusion principle

What the cosmological constant problem is — quantum field theory predicts vacuum energy 10^120 times too large

Quantum field theory overestimates vacuum energy by 10^120 times, causing the cosmological constant problem

What the strong CP problem is — why does QCD not violate CP symmetry when it has no reason not to

The strong CP problem questions why CP violation isn't observed in Quantum Chromodynamics despite theoretical possibility