Black holes are regions of space that have often been associated with destruction. These objects have such immense gravitational force that even light once trapped in it cannot escape the region. They were once thought to be rare. Albert Einstein did not believe they existed at all. Over the past several decades, astronomers have realised they are not so unusual. Super-massive ones, millions or billions of times as hefty as the sun, seem to reside at the centre of most galaxies.

After long considering them as agents of destruction or by-products of galaxies and stars, scientists are reassessing their thinking. Now it appears they debuted in a constructive role and appeared unexpectedly after the Big Bang. In ways they have led to creation of modern structure of the universe.

“Several years ago, nobody imagined there were such monsters in the early universe,” says Penn State astrophysicist Yuexing Li. She says: “Now, we see they were essential in creating the universe’s modern structure.” Many were shocked in 2003 when a sky survey found the holes were already common nearly 13 billion years ago, when the universe was less than a billion years old. Researchers have been trying to figure out where these primordial holes came from and how they influenced cosmic events.

In August, researchers at the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University ran a supercomputer simulation of the early universe and provided a tantalising glimpse into the lives of the first black holes. The story began 200 million years after the Big Bang, when the universe’s first stars formed.

These beasts, about 100 times the mass of the sun, were so energetic that they burnt all their hydrogen fuel in just a few million years. With no more energy from hydrogen fusion to counteract the enormous inward pull of their gravity, the stars collapsed until all of their mass was compressed into a point of infinite density.

The first-generation holes were smaller than the big sizes we talk about today. They grew slowly by adding just 1 per cent to their bulk in the next 200 million years. This is because the hyperactive stars that gave them birth had blasted away most of the nearby gas they could have consumed.

But these medium-size holes left a big dent by carrying out a form of stellar birth control. Radiation from the material falling into the holes heated surrounding clouds of gas to about 5,000 degrees Fahrenheit, so hot that the gas could no longer easily combine. “You couldn’t really form stars in that stuff,” says Marcelo Alvarez, lead author of the Kavli study.

Even as Alvarez’s computer model offered a glimpse into the universe’s childhood, it sowed confusion about what happened next. In 2007, scientists spotted a billion-solar-mass black hole that existed some 840 million years after the Big Bang, the earliest and most distant one ever observed. Last September another research team announced it had found a large, star-forming galaxy surrounding it. These discoveries were puzzling. About 400 million years after the Big Bang, the universe still consisted of spread out stars and small starving black holes. Less than 500 million years later, it was full of monster black holes embedded in vast galaxies. How did things change so rapidly?

The answer is in Yuexing Li’s recent work. Her work shows that the first holes were enveloped by halos of dense, invisible matter tens of thousands of times more massive. Together, these constituted “protogalaxies” that is building blocks of today’s galaxies.

During a period of frequent, violent collisions among the protogalaxies, their resident black holes experienced rapid growth spurts by merging with one another and gobbling up new supplies of gas and dust. A 100-solar-mass black hole ballooned into a billion-mass beast within 800 million years, and in dense regions that growth could have occurred even more quickly. During this dynamic period, Li’s model shows, black holes suddenly became a lot more star-friendly.

Merging protogalaxies sent out shockwaves that compressed dense clumps of gas, helping trigger widespread star birth even in regions previously dominated by black hole radiation. In a remarkably short period of time, black holes shifted from lightweight bullies to super-massive centrepieces of star-breeding galaxies.

“There are aggressive campaigns to search for the first supermassive black holes,” Li says. The recently refurbished Hubble Space Telescope will aid this search. Hubble’s successor, the James Webb Space Tele­scope, will delve deeper following its 2014 launch.

The writer is a doctoral candidate at Carnegie Mellon University, Pittsburgh, PA and also knowledge editor at Financial Chronicle