Physicists using the Large Hadron Collider have detected the first clear evidence of a wake left by a quark slicing through trillion-degree nuclear matter, suggesting the primordial soup of the universe was more liquid-like than previously thought. The discovery, published December 25, 2025, in Physics Letters B, comes from the CMS collaboration at CERN.

The experiment recreated conditions from microseconds after the Big Bang by colliding heavy atomic nuclei at near-light speed. These collisions briefly melt nuclei into an exotic state called quark-gluon plasma, where quarks and gluons flow collectively like an ultrahot liquid rather than behaving as separate particles. The plasma droplet, about 10,000 times smaller than an atom, vanishes almost instantly but provides crucial insights into early-universe physics.

By analyzing correlations between Z bosons and hadrons, researchers identified a less-than-1% suppression in particle production behind high-energy quarks as they traversed the plasma. This subtle dip represents the first clear detection of a wake in Z-tagged events, offering a new window into the properties of the primordial matter that filled the early universe before cooling into protons, neutrons, and eventually atoms.