Simon van der Meer
van der Meer, Simon, 1925–2011, Dutch physical engineer. He spent nearly his entire career at CERN, where he did his most important work with Carlo Rubbia. They discovered the W and Z particles, which convey the weak force, one of nature's four fundamental forces (see weak interactions); he employed stochastic cooling to create the high-energy beams of antiprotons that were used in the proton-antiproton collisions that led to the particles' discovery. For their work, van der Meer and Rubbia were awarded the 1984 Nobel Prize in Physics.