The scientists, hailing from the United States, Germany and Sweden, used extraordinarily short pulses of light to track the way electrons move in atoms and create the chemical bonds necessary for the formation of molecules.

It’s time for the 2023 Nobel Prizes. Here’s what you need to know.

“The reason we care about the electron is all chemistry … is all about how electrons interact,” American Physical Society President Robert Rosner said after the prize announcement. “All atoms are a nucleus surrounded by clouds of electrons, and it’s these clouds of electrons that interact with each other that allow you to make molecules, to assemble stuff.”

Agostini is a professor emeritus at Ohio State University. Krausz has positions at the Max Planck Institute of Quantum Optics and the Ludwig Maximilian University of Munich. L’Huillier is a professor at Lund University in Sweden.

L’Huillier is the fifth woman ever honored with a Nobel in physics. She was teaching at Lund University when her phone rang several times Tuesday, and she finally answered the call from the academy.

“The last half-hour of my lecture was difficult to do,” she said by phone during the Nobel news conference. “I am very touched at the moment. As you know, there are not so many women who get this prize, so it’s very, very special.”

Electrons are workhorses in the physical processes of the world as we know it, but they are small and elusive entities with the head-scratching quality of appearing to act like both a particle and a wave. At this incredibly tiny scale, the physical world has been difficult to describe except with approximations, but the three laureates found ways to track electrons with new technologies.

The work honored Tuesday comes from a discipline known as attosecond physics, so called because the pulses of light used in the experiments last only an attosecond, a period so brief that scientists say there are as many attoseconds in one second as there have been seconds since the dawn of time roughly 13.8 billion years ago.

“At this time scale, time stands still for everything except the electrons,” said Olle Eriksson, a physicist at Uppsala University in Sweden.

Attosecond physics holds the potential for scientists to better understand how electrons move through different materials, such as electrical conductors, and to help them better identify molecules in medical diagnostics. These breakthroughs are relevant across many scientific fields, including biology and chemistry.

Earlier advances in the field allowed scientists to scrutinize the motion of atoms within molecules and gain a better understanding of conductivity, said Susan L. Dexheimer, professor emerita at Washington State University and chair of the American Physical Society division of laser science. Attosecond pulses allow scientists to probe even deeper into the submicroscopic realm, to monitor electrons within atoms.

“Shorter-duration light pulses make possible measurements on faster time scales, acting like a strobe light to ‘freeze’ fast motions,” Dexheimer said Tuesday in an email.

Rosner offered the analogy of a ceiling fan: When it’s whirring away, the blades are not individually visible. But hit the fan with a strobe light, and you can see where each blade is at that moment. Now do the same with an atom and hit it with attosecond light pulses. The technique allows an understanding of what electrons are doing in narrow slices of time.

“It opens up a window to a world that to us before was just a blur,” Rosner said.

The ceiling fan analogy isn’t perfect, though. The problem with studying electrons isn’t that they move fast but that they move a very short distance, Rosner said.

It is hard to predict who or what will receive the Nobel in physics because there is such a wide range of disciplines in the field — including the study of subatomic particles, research on material properties, and the scrutiny of galaxies at the edge of the visible universe. The academy often honors work performed many decades earlier.

The Nobel rules are simultaneously restrictive in two ways: Only people who are still living can be awarded the prize, and no more than three people can receive the prize for any particular achievement.

Last year the Nobel physics prize went to three researchers for breakthroughs in quantum information science, a field that promises someday to revolutionize computing and the transfer of information via “quantum teleportation.” The 2021 prize honored research relevant to climate change, while the 2020 prize centered on discoveries about black holes.