Issues

Two rival groups of observers have concluded that the gravitational slowing of the Hubble expansion is being opposed by a repulsive cosmological constant, or something even more exotic.

Do the spins and charges associated with copper and oxygen atoms in high‐temperature superconductors arrange themselves in orderly rows in the copper oxide plane? Recent studies suggest that not just one but several families of the cuprates may feature such stripes, although in most cases the stripes are not static but fluctuate with time and position.

Neither purely viscous nor perfectly elastic, polymeric fluids have a fading memory of their undeformed shape and display spectacular phenomena not seen in Newtonian fluids.

Despite being among the most studied physical systems, low‐temperature mixtures of helium‐3 and helium‐4 continue to exhibit phenomena that fascinate and surprise.

The first orbiting observatory dedicated to high‐precision parallax measurement has completed its task. We now have direct distance determinations with accuracies better than 10% to more than 20 000 stars.