November 11, 2013
When Two Black Holes Become One
Every fan of science fiction knows about black holes, huge objects in space with gravitational fields so strong that not even light can escape them. They have often been used to explain the unexplainable in many novels, television shows, and movies. Need your character shot across the galaxy? Black hole. Travel through time? Black hole. Have an entire solar system wiped out in an instant? Black hole. Speaking as a writer, they can often be the Deus ex Machina of science fiction. This is partially due to just how little we used to know about them. The mystery added to the believability of just what they could accomplish given the right circumstances. Today, we know a great deal more than we used to about these phenomenal cosmic entities, though we are still just scratching the surface. We know that they are often formed during the death of a star, as the sheer mass collapses in on itself, becoming more dense and drawing in everything around it. These black holes then attaint the status of “super-massive” as they continue to grow over billions of years. However, as we have begun realizing just how old our cosmos is, and the age of varying black holes, scientists have stumbled across an interesting puzzle. There exist several super-massive black holes that are so old that they must have come into existence shortly after the formation of the galaxy. So shortly that stars would not have had time to die and create them, much less turn these black holes into super-massive black holes. So, where did these ancient super-massive black holes come from?
Researchers at Caltech may have found the answer to this question. They believe that, early in the life of the universe, there existed super-massive stars that, unlike normal stars, stabilized against gravity by their one photon radiation (the outward flow of photons that a star generates due to their incredibly high internal temperature) pushes gases outward from the star opposite to the gravitational force that pulls the gasses back in. The more gasses such a star releases, the cooler, smaller and denser the star becomes. This process would take a couple million years until the star would then begin to collapse in on itself. It was believed that, during such a collapse, that the star would keep a relative spherical shape. But now it is theorized that the star could take on a non-spherical shape and cause the gases inside the collapsing star to clump together and form into two high-density fragments. These fragments would orbit the center of the star and each become incredibly dense themselves, picking up matter throughout the collapse of the star. These two fragments would eventually become so dense that they would each form a black hole. These two black holes would then spiral around each other for a time before eventually merging together and forming a single super-massive black hole out of a single star.
Of course, all of this is pure speculation and theory, but it is a fascinating idea. To think that a single star could create not one, but two, black holes that then combine together to form a singular super-massive black hole is incredible. Our understanding of our own universe is very little, but every step we take to understanding it broadens our horizons on just what possibilities are out there, beyond the black.
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