WIMP no-show in gamma-ray background
Although the night sky appears dark between the stars and galaxies that we can see, a strong background emission is present in other regions of the electromagnetic spectrum. At millimetre wavelengths,...
Compact star hints at vacuum polarisation
By studying an isolated neutron star, astronomers may have found the first observational indication of a strange quantum effect called vacuum birefringence, which was predicted in the 1930s by Werner ...
The dawn of a new era
One of the greatest scientific discoveries of the century took place on 14 September 2015. At 09.50 UTC on that day, a train of gravitational waves launched by two colliding black holes 1.4 billion li...
General relativity at 100
As in precision electroweak experiments, it is useful to parameterise plausible deviations from general relativity.
Catching a gravitational wave
Gravitational waves alternatively compress and stretch space–time as they propagate, exerting tidal forces on all objects in their path. Detectors such as Advanced LIGO (aLIGO) search for this subtl...
Linking waves to particles
Black holes are arguably humankind’s most intriguing intellectual construction. Featuring a curvature singularity where space–time “ends” and tidal forces are infinite, black-hole interiors ca...
n_TOF deepens search for missing cosmic lithium
An experiment at CERN’s neutron time-of-flight (n_TOF) facility has filled in a missing piece of the cosmological-lithium problem puzzle, according to a report published in Physical Review Letters. ...
Hubble misses 90% of distant galaxies
A team of astronomers has estimated that the number of galaxies in the observable universe is around two trillion (2 × 1012), which is 10 times more than could be observed by the...
Testing times for space–time symmetry
Résumé L’heure de vérité pour la symétrie de l’espace-temps La symétrie de Lorentz et la symétrie CPT sont devenues des piliers de notre compréhension de l’espace-temps. Ces symétries ...
Cosmic rays continue to confound
Résumé Les rayons cosmiques continuent de nous surprendre Le Spectromètre magnétique alpha (AMS), détecteur arrimé à la Station spatiale internationale, a enregistr&...
