Black Hole Pretenders Could Really Be Bizarre Quantum Stars

From Scientific America.com (Mar. 16):

When giant stars die, they don’t just fade away. Instead they collapse in on themselves, leaving behind a compressed stellar remnant, usually a city-size, superdense ball of neutrons appropriately called a neutron star. In extreme cases, however, most theorists believe an expiring giant star will form a black hole—a pointlike “singularity” with effectively infinite density and a gravitational field so powerful that not even light, the fastest thing in the universe, can escape once falling in. Now a new study is reinvigorating an alternate idea, that objects with names such as “black stars,” or “gravastars,” might exist midway between neutron stars and black holes. If real, these exotic stellar corpses should appear nearly identical to black holes save in one key way—they could not irretrievably swallow light.

There are good reasons to seek such alternatives, because black holes raise a host of theoretical problems. For instance, their singularities are supposedly hidden by invisible boundaries known as event horizons. Throw something into a black hole, and once it passes the event horizon it should be gone—forever—with no hope whatsoever of return. But such profound annihilation clashes with other long-cherished laws of physics that suggest the destruction of information is impossible, including information encoded within anything falling into black holes. [read more]

The universe is really weird. I have never heard of black stars before this article. Then again I am not an astrophysicist.