In 2003, NASA unveiled the first detailed full-sky map of the cosmic microwave background the microwave "echo" of the Big Bang. Scientists created the map using data collected by the Wilkinson Microwave Anisotropy Probe satellite (WMAP) over a period of 12 months. The results provide further support for the inflationary Big Bang model of the universe and reveal when the first generation of stars was created.

The data indicate that the Universe is now about 13.7 billion years old and that the earliest stars in the universe were created just 200 million years after the Big Bang. The results also support the idea of , which is expanding ever faster rather than decelerating and flat universe is made up of 4% ordinary matter, 23% dark matter and 73% dark energy.

Finding the Higgs boson and various supersymmetric particles may be the top priority of most high-energy physicists, but that has not stopped several new particles turning up out of the blue at experiments in Japan, the US, Russia and Germany. The new particles, which could have implications for the Standard Model, came as a stunning surprise to the global particle-physics community.

The first new particle was announced in April, when physicists at the BaBar experiment at Stanford, California, reported evidence for a new D-meson that might contain four quarks - although this interpretation has not been confirmed.

Two months later the first evidence ever for a pentaquark - a particle with 5 quarks - was published by US researchers. This new particle was found to have two up quarks, two down quarks and a strange antiquark. Most other particles, in contrast, are either mesons - with a quark and an antiquark - or baryons, which comprise three quarks or three anti-quarks.

A Bose-Einstein condensate is a novel state of matter in which all the atoms collapse into the same quantum state. A degenerate Fermi gas is the equivalent condensation for atoms that obey Fermi-Dirac statistics.

In July, physicists at Kyoto University in Japan said that they had observed Bose-Einstein condensation in a gas of ytterbium atoms for the first time. Ytterbium differs from most elements that have been condensed because it has two valence electrons rather than one and can be prepared in a non-magnetic state. Such novel condensates could be used in tests of fundamental symmetries.

A few weeks ago, Austrian and American researchers created a Bose-Einstein condensate of bosonic molecules from a gas of fermionic atoms. This breakthrough brings physicists closer than ever to the holy grail of ultracold atomic gas research - to observe superfluidity in a Fermi gas.

Researchers made much progress in 2003 towards creating a real quantum computer. "Qubits" - the quantum equivalents of ordinary bits - have been made with trapped photons, atoms and ions, but physicists would prefer to build real working devices with solid-state systems. This still remains a challenge.

In February, one group of physicists reported on "entangling" two qubits in a solid-state device for the first time, while a second team demonstrated a new type of superconducting qubit.

In August, a third group described how they created a logic gate using two electron-hole pairs - also known as "excitons" - in a quantum dot. Most importantly, the researchers showed that the quantum-dot system could behave like a controlled-NOT gate under certain conditions.

Magnetism

In 2003 saw cobalt enter the record books when a team of European physicists found that it has magnetic anisotropy energy (MAE) of about 9.3 meV per atom - the largest ever recorded to date. MAE controls the alignment of the atomic spins that give rise to magnetism in a material. In contrast, samarium cobalt, which is a widely used permanent magnet, has a MAE of just 1.8 meV per cobalt atom.

Physicists also observed magnetic domain walls moving on subatomic length scales for the first time.

New Superconductors

The physicists at the University of Tokyo have discovered a new superconductor made of potassium, osmium and oxygen. The work, which is yet to be published, describes a "pyrochlore" material – KOS₂O₆ - which has a superconducting transition temperature of 9.6 K and remains a superconductor in high magnetic fields.

Earlier in 2003, another group of Japanese physicists found that cobalt oxide could be transformed into a superconductor simply by adding water to it. Researchers suspect that the fundamental physics in both the high-temperature cuprate superconductors and cobalt oxide materials might be the same.

Laser-based nuclear transmutation