Editing Quark star (section)

===Stability and strange quark matter===
Ordinary quark matter consisting of up and down quarks has a very high [[Fermi energy]] compared to ordinary atomic matter and is stable only under extreme temperatures and/or pressures. This suggests that the only stable quark stars will be neutron stars with a quark matter core, while quark stars consisting entirely of ordinary quark matter will be highly unstable and re-arrange spontaneously.<ref name="Witten">{{cite journal |last1=Witten |first1=Edward |title=Cosmic separation of phases |journal=Physical Review D |volume=30 |issue=2 |pages=272–285 |date=1984 |doi=10.1103/PhysRevD.30.272 |bibcode=1984PhRvD..30..272W }}</ref><ref>{{cite journal |title=Strange matter |last1=Farhi |first1=Edward |last2=Jaffe |first2=Robert L. |journal=Physical Review D |volume=30 |issue= 11 |pages=2379 |date=1984 |bibcode=1984PhRvD..30.2379F |doi=10.1103/PhysRevD.30.2379}}</ref>

It has been shown that the high Fermi energy making ordinary quark matter unstable at low temperatures and pressures can be lowered substantially by the transformation of a sufficient number of up and down quarks into [[strange quark]]s, as strange quarks are, relatively speaking, a very heavy type of quark particle.<ref name="Witten" /> This kind of quark matter is known specifically as [[strange quark matter]] and it is speculated and subject to current scientific investigation whether it might in fact be stable under the conditions of interstellar space (i.e. near zero external pressure and temperature). If this is the case (known as the Bodmer–[[Edward Witten|Witten]] assumption), quark stars made entirely of quark matter would be stable if they quickly transform into strange quark matter.<ref name="Weber">{{Cite web|title=Strange-matter Stars |url=https://cds.cern.ch/record/278675 |last1=Weber |first1=Fridolin |last2=Kettner |first2=Christiane |last3=Weigel |first3=Manfred K. |last4=Glendenning |first4=Norman K. |journal= |date=1995 |access-date=2020-03-26 |archive-date=2022-03-22 |archive-url=https://web.archive.org/web/20220322124648/https://cds.cern.ch/record/278675 |url-status=live }} in {{cite book |title=International Symposium on Strangeness and Quark Matter, Kolymbari, Greece, 1-5 Sep 1994 |pages=308–317 |publisher=World Scientific |location=Singapore |editor-last1=Kumar |editor-first1=Shiva |editor-last2=Madsen |editor-first2=Jes |editor-last3=Panagiotou |editor-first3=Apostolos D. |editor-last4=Vassiliadis |editor-first4=G. }}</ref>