LHC creates world's smallest liquid droplets

Scientists at the Large Hadron Collider (LHC) claim to have recreated the world's tiniest droplets of a primordial state of matter that last existed moments after the Big Bang, some 13.8 billion years ago.
Evidence of the minuscule droplets was extracted from the results of colliding protons with lead ions at velocities approaching the speed of light.
According to the scientists, these short-lived droplets are the size of three to five protons.
"With this discovery, we seem to be seeing the very origin of collective behaviour," said Julia Velkovska, professor of physics at Vanderbilt University who serves as a co-convener of the heavy ion program of the CMS detector.

"Regardless of the material that we are using, collisions have to be violent enough to produce about 50 sub-atomic particles before we begin to see collective, flow-like behaviour," said Velkovska.
These tiny droplets "flow" in a manner similar to the behaviour of the quark-gluon plasma, a state of matter that is a mixture of the sub-atomic particles that makes up protons and neutrons and only exists at extreme temperatures and densities.

Cosmologists propose that the entire universe once consisted of this strongly interacting elixir for fractions of a second after the Big Bang when conditions were dramatically hotter and denser than they are today.

Now that the universe has spent billions of years expanding and cooling, the only way scientists can reproduce this primordial plasma is to bang atomic nuclei together with tremendous energy.
Scientists have been trying to recreate the quark-gluon plasma since the early 2000s by colliding gold nuclei using the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory.
This exotic state of matter is created when nuclei collide and dump a fraction of their energy into the space between them. When enough energy is released, it causes some of the quarks and gluons in the colliding particles to melt together to form the plasma.

The RHIC scientists had expected the plasma to behave like a gas, but were surprised to discover that it acts like a liquid instead.
The new observations are contained in a paper submitted to the journal Physical Review D.