Big Bang Query: Mapping how matter became a mysterious liquid - Phys.org

Big Bang Query: Mapping how matter became a mysterious liquid - Phys.org

A new perspective of the STAR detector at RHIC, seen through crystal ball refraction photography. The photo was a finalist for the Photowalk of the Brookhaven National Laboratory in 2018. Source: Joe Caggiano

The leading theory of the beginning of the universe is the Big Bang, which states that the universe existed as a singularity 14 billion years ago, a one-dimensional point with a large number of fundamental particles. Extremely high heat and energy caused it to bloat and then expand into the cosmos as we know it – and the expansion continues today.


The first result of the Big Bang was an intense hot and energetic liquid that lasted for only microseconds and was about 10 billion degrees Fahrenheit (5.5 billion Celsius). This liquid contained nothing less than the building blocks of all matter. As the universe cooled, the particles disintegrated or united, which led to … well, everything.

Quark-Gluon-Plasma (QGP) is the name for this mysterious substance, which is so named because it consists of quarks – the fundamental particles – and gluons, which the physicist Rosi J. Reed describes as "what quarks talk to each other" ,

Scientists like Reed, an assistant professor at Lehigh University's Institute of Physics, whose research includes experimental high-energy physics, can not go back to study how the universe began. Thus, they re-create the circumstances by colliding heavy ions like gold at near-light speed, creating an environment 100,000 times hotter than the sun's interior. The collision mimics how the quark-gluon plasma became matter after the Big Bang, but the other way round: The heat melts the protons and neutrons of the ions, releasing the quarks and gluons hidden inside.

Currently, there are only two accelerators worldwide that are capable of colliding heavy ions – and only one in the USA: the Relativistic Heavy Ion Collider (RHIC) of the Brookhaven National Lab. It is about three hours drive from Lehigh in Long Island, New York.