WOLFS M Creating a Little Big Bang on

ANKIND HAS ALWAYS been fascinated with looking back in time. Historians and archaeologists use historical records and artifacts to trace back the evolution of mankind. Biologists use evolutionary theory to describe the development of life on Earth. The Earth is relatively young by astronomical standards, about 4.6 billion years, and the Universe is even older. It is believed that the Universe was created about 15 billion years ago, in an event that is often referred to as the “ Big Bang.” Astronomers provide us with a wealth of information about the evolution of Universe by probing it at ever-increasing distances from the Earth. These observations can take us back in time by about 14 billion years, at which time star formation started to occur. Nuclear and atomic physicists provide us with a detailed description of the evolution of the early Universe, between a few seconds after the Big Bang and the start of star formation. During this period, the basic building blocks of matter, protons and neutrons, were formed, and light nuclei and atoms were created. Although these different areas of science allow us to look back billions of years in time, much uncertainty remains about the evolution of the Universe during the fi rst few seconds after the Big Bang. Many fundamental questions, such as why the Universe is dominated by matter instead of having equal amounts of matter and antimatter, can only be answered if we know in detail what happened during the fi rst few seconds after the Big Bang. To recreate the conditions that existed a few microseconds after the Big Bang, a new accelerator facility was built at Brookhaven National Laboratory (BNL) in New The Relativistic Heavy-Ion Collider