Astronomy prof Bob Abraham is on a quest for the Holy Grail… of astronomy, that is. He gave the last lecture in the Cosmic Frontiers lecture series last Friday, explaining to a spellbound audience just what that this quest is.
It took three minutes after the Big Bang, said Abraham, to make all of the hydrogen and helium in the universe. This in and of itself is an incredible thing to fathom. It did, however, make for an incredibly boring universe.
For about one billion years after the Big Bang there were no stars, no galaxies and no cosmic debris; our sun was billions of years from being born and humans were a tiny twinkle in the universe’s eye.
Then, something strange and fantastic occurred: stars started to form in this soup of hydrogen and helium that was our universe. The how and why of it continues to perplex the most brilliant astrophysicists of our day.
That is because our knowledge of the universe leads us to believe that stars are born from the debris of other stars. This raises the question: in the beginning, if the universe consisted of a hydrogen-helium soup without any stars, how did the first stars form?
Abraham has one idea: namely, that the hydrogen elsewhere in the universe was different from hydrogen here on earth. It existed as a plasma.
Plasma is a state of matter wherein all the electrons are stripped from atoms. As Abraham explained, this state is akin to everyone in the audience taking off their clothes and running in one direction while their clothes ran off in another. (His analogy met with much laughter, and some cringing.)
Hydrogen plasma on that large of a scale would have collapsed on itself on large enough scale to begin the formation of galaxies. The elusive question that is the obsession of today’s top minds is what substance turned the hydrogen gas to plasma a billion years after the universe was created.
No one knows what this substance is. It is known only as First Light, and is the Holy Grail of astronomy.
The Grail Race is sweeping the globe, and Professor Abraham and the University of Toronto are at the front of the pack that is trying to determine what First Light is-and win a coveted Nobel prize for their efforts. He and his team use powerful ground-based telescopes to peer deep into space-and hence further back in time-in search of their elusive goal.
Abraham is optimistic that his team will win the Grail Race. “This has been a great hundred years for the University of Toronto,” he said, “but you ain’t seen nothing yet.” Gentlemen, start your engines.
