“Nuclear pasta” may exist inside neutron stars 

Scientists have conducted a simulation of matter inside a neutron star. According to it, in its outer layers, matter can be sufficiently diluted so that the nuclei of atoms do not completely collapse. In such conditions, elementary particles can look like “nuclear pasta”. 

There may be “nuclear pasta” inside neutron stars. Source: www.sciencenews.org

How dense a neutron star is

Researchers from the Department of Physics at the Technical University of Darmstadt and the Niels Bohr Institute in Copenhagen recently published a paper in Physical Review Letters on the internal structure of neutron stars. They argue that there may be something inside them that they call “nuclear pasta”.

Neutron stars are the cores of stars that once exploded as supernovae. At some point, the outer shells of these luminaries flew off, and the inner shells were compressed so hard that the atoms were destroyed. A little more time and these objects would have turned into black holes, but until some point the energy of the elementary particles is stronger than gravity.

Because of all this, neutron stars are almost as amazing as black holes. They have a number of incredible properties. And the way they are organised inside is still a mystery to scientists, who have never seen a substance with a density five times higher than that of an atomic nucleus.

Nuclear pasta

Actually, the new study began with the researchers taking another look at the model of a neutron star, which is 95% neutrons formed by electrons being “squeezed” into protons and 5% protons that escaped this fate. They assumed that the density of the outer layers should be lower and that some atomic nuclei might survive in such conditions.

They carried out numerical simulations and concluded that this was indeed the case. However, some of the neutrons should still be “squeezed out” of the nuclei and form a medium. Scientists again turned to calculations and concluded that protons can also be squeezed out of nuclei.

In addition, under such conditions, these two types of particles, which are collectively called nucleons, can freely exist in the form of filaments or plates. This phenomenon is called “nuclear pasta” by scientists. The association with various dishes based on them can be continued for a long time, as scientists do not know exactly how all those things interacts with each other.

“Nuclear pasta” is just one of many attempts to look inside a neutron star. Even though it does not violate any physical laws like a black hole, it is extremely difficult to verify the correctness of theoretical constructions. If we ever get to one of these objects, it will be almost impossible to take a sample from its surface due to the high gravity.

Source: phys.org