What happened in first microsecond of Big Bang?

Researchers at the University of Copenhagen – Faculty of Science have investigated what happened to a specific kind of plasma – the first matter ever to be present – during the first microsecond of the Big Bang. Their findings provide a piece of the puzzle to the evolution of the universe, as people know it today.

About 14 billion years ago, our universe changed from being a lot hotter and denser to expanding radically- a process that scientists have named ‘The Big Bang’. And even though we know that this fast expansion created particles, atoms, stars, galaxies and life as we know it today, the details of how it all happened are still unknown.

Now a new study performed by researchers from the University of Copenhagen reveals insights into how it all began.

“We have studied a substance called Quark-Gluon Plasma that was the only matter, which existed during the first microsecond of Big Bang. Our results tell us a unique story of how the plasma evolved in the early stage of the universe,” explains You Zhou, Associate Professor at the Niels Bohr Institute, University of Copenhagen.

“First the plasma that consisted of quarks and gluons was separated by the hot expansion of the universe. Then the pieces of quark reformed into so-called hadrons. A hadron with three quarks makes a proton, which is part of atomic cores. These cores are the building blocks that constitute earth, ourselves and the universe that surrounds us,” he adds. The Quark-Gluon Plasma (QGP) was present in the first 0.000001 seconds of the Big Bang and thereafter it disappeared because of the expansion.