A Cosmologist Explains How Quark Stars Form

First, cram several suns’ worth of mass into a volume no bigger than a typical city, and imagine they are primarily made of free-floating quarks, one of the building blocks of all atoms.
Astrophysicists haven’t found any yet, but quark stars are made of the “strange” type of quark, and their discovery could open new avenues of research.

Herman simulates the evolution of the Universe - Institute of Theoretical Astrophysics

A Cosmologist Explains How Quark Stars Form

Quark star may hold secret to early universe

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The Mystery of Quark Stars

Mass–radius diagrams for the stable quark stars. The cases A1 to A4

A Cosmologist Explains How Quark Stars Form

The most massive neutron stars probably have cores of quark matter

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