Scientists from the University of Copenhagen have studied what happened to a particular kind of plasma — the fundamental matter ever to be present — during the first microsecond of the Big Bang. Their discoveries give a bit of the puzzle to the evolution of the universe, as we know it today.
Nearly 14 billion years ago, our universe evolved from being a lot denser and hotter to diversify completely – a process that researchers have called ‘The Big Bang’.
And even though we know that this swift expansion produced atoms, particles, stars, galaxies, and life as we know it today, the details of how it all occurred are still unexplained.
Now the latest research conducted by scientists from the University of Copenhagen explains insights into how it all started.
“We have examined the particles know as Quark-Gluon Plasma that was the only matter, which existed when the first microsecond of Big Bang occurred. Our research reveals how the plasma appeared in the initial stage of the universe,” reveals You Zhou, Associate Professor at the Niels Bohr Institute, University of Copenhagen.
“First, the plasma that carries gluons and quarks was split up by the hot expansion of the universe. Then the particles of quark transformed into so-called hadrons. A hadron with three quarks produces a proton, which is an element of atomic cores. These cores are the elementary blocks that form Earth, ourselves, and the universe that surrounds us,” he adds.
The first microsecond of the Big Bang: From smooth and still to the mighty elementary blocks of life
The Quark-Gluon Plasma (QGP) was there only in the first 0.000001 seconds of the Big Bang, but it vanishes because of the expansion. However, scientists were able to regenerate this fundamental matter by using the Large Hadron Collider at CERN and trace back what happened to it.
“The collider shatter ions from the plasma with high velocity – nearly at the speed of light. This makes us able to understand how the QGP emerged from being its matter to the cores in atoms and the fundamental blocks of life,” says You Zhou.
“Furthermore, the scientists also developed an algorithm that can explain the combined expansion of more produced elements at once, than ever achievable before. Their outcomes reveal that the QGP used to be a fluent liquid form and that it separates itself from other matters by regularly switching its shape over time.
“For many years scientists assumed that the plasma was a kind of gas, but our study confirms the newest milestone measurement, where the Hadron Collider confirmed that QGP was fluent and had a steady soft texture like water. The latest details we provide is that the plasma has evolved its shape over time, which is quite remarkable and distinct from any other matter we know and what we would have anticipated,” says You Zhou.
One step closer to resolving the mystery of the Big Bang
Yet, this might look like a small detail, it leads us one step closer to resolving the mystery of the Big Bang and how the universe evolved in the first microsecond, he elaborates.
“Each finding is a fundamental brick that improves our possibilities of getting out the truth about Big Bang. It has taken us nearly 20 years to discover that the Quark-Gluon Plasma was fluent before it transformed into hadrons and the fundamental blocks of life. Hence, our latest information on the ever-changing form of the plasma is an important finding for us,” You Zhou concludes.
“Measurements of mixed harmonic cumulants in Pb–Pb collisions at TeV” by ALICE Collaboration, 11 May 2021, Physics Letters B.
The research has just been issued in the journal Physics Letters B and is conducted by You Zhou together with Zuzana Moravcova, who is a Ph.D. at the Niels Bohr Institute at the University of Copenhagen.