Physics Stories of the Year for 2001

In cosmology, the observations of second and third peaks in the spectrum of the cosmic microwave background (Update 537), the detection of the "re-ionization" era in the early universe (555), and some tentative evidence that the fine structure constant is changing (552); in the physics of atoms, the effective stopping and storing of light in a gas (521); in particle physics the observation of CP violation in the decay of B mesons (525, 547); in condensed matter physics, the observation of superconductivity at 117 K in a crystal of carbon-60 (555) and at 40 K in MgB (526, 530); Bose-Einstein condensate on a chip (559), in helium (532), and the topic meriting the 2001 Nobel Prize (560); in nuclear physics the first experimental formulation of a nuclear liquid-gas phase diagram (upcoming Update). Other stories include the retraction of the element 118 discovery (550); further evidence for neutrino oscillations, at the new Sudbury detector (544); doubly strange nuclei (552); chaos insights on weather (543); crystallization using sound waves (541); room-temperature spin injection for spintronics (543); quantum entanglement of macroscopic gas clouds (558); quantum holography (566); attosecond pulses (567).