Q star

A Q-star, also known as a grey hole, is a hypothetical type of a compact, heavy neutron star with an exotic state of matter. Such a star can be smaller than the progenitor star's Schwarzschild radius and have a gravitational pull so strong that some light, but not all photons, can escape.^{[citation needed]} The Q stands for a conserved particle number. A Q-star may be mistaken for a stellar black hole.^[1]

Types of Q-stars

Q-ball^[2]
B-ball, stable Q-balls with a large baryon number B. They may exist in neutron stars that have absorbed Q-ball(s).^[2]

References

^ *Miller, J. C.; Shahbaz, T.; Nolan, L. A. (1998). "Are Q-stars a serious threat for stellar-mass black hole candidates?". Monthly Notices of the Royal Astronomical Society. 294 (2): L25 – L29. arXiv:astro-ph/9708065. Bibcode:1998MNRAS.294L..25M. doi:10.1046/j.1365-8711.1998.01384.x.
^ ^a ^b Kusenko, Alexander (2006). Properties and signatures of supersymmetric Q-balls. workshop on Exotic Physics with Neutrino Telescopes. Uppsala, Sweden. arXiv:hep-ph/0612159. Bibcode:2006hep.ph...12159K.

v t e Black holes
Outline
Types	BTZ black hole Schwarzschild Rotating Charged Virtual Kugelblitz Supermassive Primordial Direct collapse Rogue Malament–Hogarth spacetime
Size	Micro Extremal Electron Stellar Microquasar Intermediate-mass Supermassive Active galactic nucleus Quasar LQG Blazar OVV
Formation	Stellar evolution Gravitational collapse Neutron star Related links Tolman–Oppenheimer–Volkoff limit White dwarf Related links Supernova Micronova Hypernova Related links Gamma-ray burst Binary black hole Quark star Supermassive star Quasi-star Supermassive dark star X-ray binary
Properties	Astrophysical jet Gravitational singularity Ring singularity Theorems Event horizon Photon sphere Innermost stable circular orbit Ergosphere Penrose process Blandford–Znajek process Accretion disk Hawking radiation Gravitational lens Microlens Bondi accretion M–sigma relation Quasi-periodic oscillation Thermodynamics Bekenstein bound Bousso's holographic bound Immirzi parameter Schwarzschild radius Spaghettification
Issues	Black hole complementarity Information paradox Cosmic censorship ER = EPR Final parsec problem Firewall (physics) Holographic principle No-hair theorem
Metrics	Schwarzschild (Derivation) Kerr Reissner–Nordström Kerr–Newman Hayward
Alternatives	Nonsingular black hole models Black star Dark star Dark-energy star Gravastar Magnetospheric eternally collapsing object Planck star Q star Fuzzball Geon
Analogs	Optical black hole Sonic black hole
Lists	Black holes Most massive Nearest Quasars Microquasars
Related	Outline of black holes Black Hole Initiative Black hole starship Black holes in fiction Big Bang Big Bounce Compact star Exotic star Quark star Preon star Gravitational waves Gamma-ray burst progenitors Gravity well Hypercompact stellar system Membrane paradigm Naked singularity Population III star Supermassive star Quasi-star Supermassive dark star Rossi X-ray Timing Explorer Superluminal motion Timeline of black hole physics White hole Wormhole Tidal disruption event Planet Nine
Notable	Cygnus X-1 XTE J1650-500 XTE J1118+480 A0620-00 Sagittarius A* Centaurus A Phoenix Cluster PKS 1302-102 OJ 287 SDSS J0849+1114 TON 618 MS 0735.6+7421 NeVe 1 Hercules A 3C 273 Q0906+6930 Markarian 501 ULAS J1342+0928 PSO J030947.49+271757.31 AT2018hyz Swift J1644+57
Category Commons

Q star

Types of Q-stars

See also

References

Further reading