An electroweak star is a theoretical type of

exotic star An exotic star is a hypothetical compact star composed of exotic matter (something not made of electrons, protons, neutrons or muons), and balanced against gravitational collapse by degeneracy pressure or other quantum properties. Exotic stars incl ...

, whereby the gravitational collapse of the

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

is prevented by

radiation pressure Radiation pressure is the mechanical pressure exerted upon any surface due to the exchange of momentum between the object and the electromagnetic field. This includes the momentum of light or electromagnetic radiation of any wavelength that is a ...

resulting from

electroweak burning In theoretical physics, a chiral anomaly is the anomalous nonconservation of a chiral current. In everyday terms, it is equivalent to a sealed box that contained equal numbers of left and right-handed bolts, but when opened was found to have mor ...

, that is, the energy released by conversion of

quark A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly ...

s to

lepton In particle physics, a lepton is an elementary particle of half-integer spin (spin ) that does not undergo strong interactions. Two main classes of leptons exist: charged leptons (also known as the electron-like leptons or muons), and neutr ...

s through the

electroweak force In particle physics, the electroweak interaction or electroweak force is the unified description of two of the four known fundamental interactions of nature: electromagnetism and the weak interaction. Although these two forces appear very diffe ...

. This process occurs in a volume at the star's core approximately the size of an

apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple trees are cultivated worldwide and are the most widely grown species in the genus '' Malus''. The tree originated in Central Asia, where its wild ancest ...

, containing about two Earth masses and reaching temperatures on the order of 10¹⁵ K.

Formation

The stage of life of a star that produces an electroweak star is theorized to occur after a

supernova A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or whe ...

collapse. Electroweak stars are denser than

quark star A quark star is a hypothetical type of compact, exotic star, where extremely high core temperature and pressure has forced nuclear particles to form quark matter, a continuous state of matter consisting of free quarks. Background Some massive ...

s, and may form when quark

degeneracy pressure Degenerate matter is a highly dense state of fermionic matter in which the Pauli exclusion principle exerts significant pressure in addition to, or in lieu of, thermal pressure. The description applies to matter composed of electrons, protons, ...

is no longer able to withstand

gravitational attraction In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the strong ...

, but may still be withstood by electroweak burning radiation pressure. This phase of a star's life may last upwards of 10 million years. The energy output of an electroweak star is limited by the quark supply rate, which is dictated by gravitational collapse. Each interaction converts nine quarks into three anti-leptons, violating conservation of

baryon In particle physics, a baryon is a type of composite subatomic particle which contains an odd number of valence quarks (at least 3). Baryons belong to the hadron family of particles; hadrons are composed of quarks. Baryons are also classifie ...

and

lepton number In particle physics, lepton number (historically also called lepton charge) is a conserved quantum number representing the difference between the number of leptons and the number of antileptons in an elementary particle reaction. Lepton number ...

while preserving B−L, generating around 300 GeV per interaction. The energy diffuses out of the star as a mixture of neutrinos and photons. Electroweak stars could be identified through the equal number of neutrinos emitted of all three generations, taking into account neutrino oscillation.

Formation

See also

References

Sources

Further reading

External links