Kevin Pitts: Questions and Quarks

In 1995, Kevin Pitts, dean of the College of Science, was part of a team of scientists and engineers at Fermilab who confirmed the existence of something called the “top quark.”

A physicist at Lawrence Berkeley National Laboratory called it “one of the ten most important accomplishments in this century in this field.”

We asked Pitts to explain what a quark is, and why it is important.

“In many ways, a quark is the fundamental building block of almost everything in our experience,” he began. 

But in school back in the day, they told us that atoms were the fundamental building block?

“Ok, well, 130 years ago or so we kind of had this sense that there were small particles that make up materials and they were the building blocks,” he said.

Scientists called those building blocks atoms, and then they found out about protons and electrons, then they learned about neutrons. In the 1960s, a series of experiments discovered particles inside protons and neutrons, and those were named quarks.

Quarks are naturally created when cosmic rays collide with particles in the air. They are created by scientists by forcing the collision of particles in an accelerator. Specifically, in the Collider Detector Fermilab (CDF), where Pitts spent much of his research career to this point. 

To create a top quark at Fermilab, the Tevatron — then the most powerful collider in the world — has to produce as many as 10 billion collisions to make one pair of quarks.

“Now you can say that a proton is a unit,” Pitts said, as he spreads the fingers of each hand and curves them to form a ball, “and it has these quarks that are circling around inside it.”

He gets very animated as he ponders it. Not the discovery, but from all the discoveries that are yet to be made.

“Where does it all end? How does this stuff fit together to make the universe as we know it, ranging from the iron in the earth’s crust to the hydrogen that makes the sun burn, to the oxygen? How does it fit together to make the stars, make planets, make people? 

“The list of outstanding questions is actually more fascinating than the list of questions that have been answered. This is what keeps us going, this is what keeps us dreaming and thinking about new experiments and new ideas.”

His face beams with excitement at this thought.