CERN's Large Hadron Collider (LHC), currently the world's most powerful accelerator, collided heavy nuclei together at the highest energies ever.

The LHC has been colliding protons at high energy levels all summer, but it has only recently started colliding large lead nuclei. CERN is conducting this research with the intention of further understanding the state of matter of the universe after the occurrence of the Big Bang.

"It is a tradition to collide ions over one month every year as part of our diverse research programme at the LHC," CERN Director-General Rolf Heuer said in a press release. "This year however is special as we reach a new energy and will explore matter at an even earlier stage of our universe."

Scientists believe that a few billionths of a second after the Big Bang, the universe was made up of a very hot, dense "primordial soup" that was made up of basic particles like quarks and gluons, according to However, one millionth of a second after the Big Bang, these particles became trapped inside protons and neutrons to create atomic nuceli. With CERN's current experiments with lead nuclei reaching the highest temperatures ever, they are closer to recreating a state of liquid matter that imitates the "primordial soup" found in the early seconds of the Universe.

"The collision energy between two nuclei reaches 1000 TeV. This energy is that of a bumblebee hitting us on the cheek on a summer day," explained Jens Jørgen Gaardhøje, head of the Danish research group at CERN. "But the energy is concentrated in a volume that is approximately 10-27 (a billion-billion-billion) times smaller. The energy concentration (density) is therefore tremendous and has never been realised before under terrestrial conditions."

In addition to insights into the Big Bang, the experiments have also allowed researchers to confirm the existence of "jet quenching," a phenomenon that occurs when the subatomic particles created during collisions lose energy as they make their way through the quark-gluon plasma, according to The International Business Times.