Thirteen discoveries that help explain why matter and energy behave as they do: -Galileo's law of falling bodies -Isaac Newton's conclusions of universal gravity -Newton's laws of motion -The second law of thermodynamics -Experiments in electromagnetism -Albert Einstein's Special Theory of Relativity and his equation E=mc2 -Quantum theory -Calculations on the nature of light -James Chadwick's discovery of the neutron -The development of superconductivity -Murray Gell-Mann's proposal of quarks -The discovery of the strong and weak nuclear forces