In the famous novel "2001: A Space Odyssey" the most intriguing protagonists are the Monoliths. They appeared with different sizes, but with one common feature: the ratio of their edges' length being 1 to 4 to 9. Last year it was reported in Science that neutron stars have something in common with these Monoliths. While the structure of these stars is mysterious and they come in different sizes, a remarkable geometrical universality leaps to the eye: certain parameters describing the spacetime around neutron stars are related in a universal manner, approximately independent of the various proposed models for the stellar structure. The Science article has been widely debated as to which extent these relations are applicable in real neutron stars. In a paper recently accepted in Physical Review Letter, researchers from CENTRA's gravity group demonstrate that universal relations between these parameters can be formulated for arbitrary fast rotating neutron stars. These results consolidate that the universality can become a powerful tool for observations of neutron stars in the future. Like the Monoliths stimulated the inventive spirit of the first men, we hope that the study of neutron stars will lead to new ideas about gravitation and the three other fundamental forces. Neutron stars may become the future ground-breaking space laboratories.
Figure: The bended spacetime around a neutron star shows universal geometric features, similar to the monoliths from the novel "2001: A Space Odyssey." Illustration by Louis (Iwa) Le Brun.
