Published in Physics World, 15 Jan 2010
For a large star, death is a bit of a squeeze. Once its nuclear fuel is spent, its core collapses, sparking a dramatic supernova explosion that blasts away the outer layers. The body left is a cold, tightly packed sphere called a neutron star, which, if massive enough, makes the ultimate collapse to a black hole.
The huge pressures inside neutron stars mean that all electrons and protons have joined so only neutrons remain. Near the centre, according to theory, these neutrons sometimes decompose into a sea of quarks, or so-called strange quark matter. A recent theory implies that this matter could form a stable ground state of nuclear matter – suggesting the existence of standalone “quark stars”. […]
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