It is late December and snow is swirling as Andrew Hamilton coasts up to his office at the University of Colorado’s Boulder campus, in the foothills of the Rockies. On a blustery day like today, most of his colleagues arrive in SUVs or at least in cars shod with all-season tires. Hamilton rides in on his Cannondale mountain bike.
Following his own path is not just a pastime to Hamilton, it is the essence of his career. For 15 years the astrophysicist has ventured nearly alone into the darkest, most impenetrable part of the universe: the inside of a black hole. “I’m not religious, but I share with religious people a desire to understand the truth about our universe. I’m focused on attaining a complete understanding of the interior of black holes,” he says, his British accent adding solemnity and power to his words. That quest has been called mad or just plain futile by colleagues who insist that the inner structure of the black hole is so extreme that it lies not only beyond exploration but beyond comprehension. Hamilton, an athletic 59-year-old
with a mane of sandy blond hair, brushes such doubt away. “I don’t necessarily avoid things others consider crazy, or I never would have gotten started in this black hole business. I’m a guy who likes adversity. I like to struggle. It’s fun to try to beat the odds.”
Black holes are massive objects that have collapsed in on themselves, creating a gravitational suction so intense that their insides become cut off from the rest of the universe. A black hole’s outer boundary, known as the event horizon, is a point of no return. Once trapped inside, nothing—not even light—can escape. At the center is a core, known as a singularity, that is infinitely small and dense, an affront to all known laws of physics. Since no energy, and hence no information, can ever leave that dark place, it seems quixotic to try peering inside. As with Las Vegas, what happens in a black hole stays in a black hole.
Where other scientists see the end point of scientific inquiry, Hamilton sees the beginning, an entrée to an extraordinary and unexplored terrain. He pictures a waterfall of space and time pouring over the event horizon to an inner zone where “all the light and material that ever fell into the black hole piles up in a tremendous collision, generating a maelstrom of energy and an infinitely bright, blinding flash of light.” Then he jumps in his barrel and takes the plunge.
Hamilton’s work has the flavor of a charming personal obsession, but it also has huge implications. Black holes are connected to some of the most basic phenomena in our universe. They may have been among the universe’s earliest structures, influencing the formation and evolution of galaxies like our own. Almost every large galaxy still houses a monster black hole, up to billions of times the mass of our sun, at its center. Much smaller black holes (typically weighing several times as much as the sun) result from the explosive death of ultrabright stars, so these dark objects reveal secrets about the stellar life cycle. Our galaxy alone may contain 100 million such objects. And because of parallels between black holes and the Big Bang, black holes might help explain how the universe was formed. In some exotic physics theories, they could even house wormholes—hypothetical shortcuts across space and time—or function as nurseries where other universes are born.
“Black holes are vaults harboring some of the most fundamental truths of the cosmos,” Hamilton says. By applying the laws of physics, he is trying to unlock the secrets inside.
THROUGH THE STARGATE
Hamilton began his journey to the heart of darkness somewhat unwittingly as he carried out the most straightforward part of his job: teaching undergraduate astronomy at the University of Colorado. It was 1996, and Hamilton had asked some of his students to make a black hole show for the university’s Fiske Planetarium. They created a variety of short presentations, highlighting various aspects of these astrophysical objects. For the finale of their presentation, the students tacked on a 40-second clip from Stargate, a 1994 movie in which an Egyptologist (James Spader) pushes through the fluidlike surface of the “stargate,” a 20-foot-wide, hieroglyph-adorned ring providing passage to a parallel world. Hamilton’s heart sank. The movie’s set pieces bore no relationship to real physics. But when Spader passed through the wormhole, encountering a multicolored, psychedelic display of geometric patterns and streaming lights, the students cheered and Hamilton began to change his mind. Science-based visualizations could be an effective way to teach people about black holes—“maybe the best way,” he thought. He vowed to create his own depiction of the descent through a black hole, one based not on Hollywood sleight of hand but on the best physics he could find.