Pursuing purpose through physics
Gary Wall, a 1970 CU Boulder physics graduate, won the Los Alamos Medal in recognition of more than 50 years of distinguished work at Los Alamos National Laboratory
During the summer of 1970, his first year working at the Los Alamos National Laboratory in New Mexico, Gary Wall was something of a hippie and wore a large peace sign pendant to work most days. He still has it, and there’s nothing subtle about it.
“I initially had reservations about working there,” Wall recalls of his graduate research assistant position at the physical and scientific home of the Manhattan Project. “I applied because my girlfriend at the time was from Los Alamos.”
However, it wasn’t very long before “I became convinced the nuclear deterrent is what is keeping us out of world wars,” he says. “The purpose of a nuclear deterrent is to keep the peace. I did struggle that first summer when I found out that I was going to be working in the nuclear weapons group—I struggled with whether that’s really what I wanted to do—but every day I learned more about how we’re supporting the work of protecting the country and protecting the world from a third world war, hopefully.”
Since that summer of 1970, a month after he graduated the University of Colorado Boulder with a bachelor’s degree in physics, Wall has become one of the most distinguished designers in the Los Alamos National Laboratory (LANL) Weapons Physics group. In recognition of his more than 50 years of work, he won the Los Alamos Medal, the laboratory’s highest honor.
The Los Alamos Medal recognizes recipients who have made contributions that changed the course of science, made major enhancement to the laboratory’s ability to achieve its mission or established a major direction for the laboratory and the nation.
“All the fields in physics are challenging, and they’re stimulating,” Wall says. “National labs are great places to work, and physics is a great field. There are always new frontiers to investigate in physics, and even 50 years later, I’m still making discoveries in physics.”
A love for science
Growing up in Englewood, Colorado, Wall was always drawn to science—charting his own path in a family in which his father did construction and remodeling work and his mother was a homemaker. He joined his father on jobs during summer months and dove back into the solution-finding and figuring-things-out of science when he resumed classes at Englewood High School.
He won a —“the only way I could attend college, because we couldn’t have afforded it otherwise,” Wall says—and began classes at CU Boulder in 1965, studying physics and math. The math was to help him keep up with the physics, he says.
His junior year abroad in England explains why he graduated in 1970 instead of 1969, he says, “but it was a fun year out. It was really interesting to study American history from a British perspective and to study British literature in the country where it was written.”
After graduating, and encouraged by his girlfriend, Wall applied for and received a graduate research-assistant position at LANL. He thought it would just be for the summer, since an advisor at CU recommended he pursue graduate studies at a different university than where he completed his undergraduate work. So, in the fall of 1970, he headed to the University of Minnesota.
“I didn’t like the big city, and I definitely didn’t like six months of winter,” he says, so the following summer he headed back to Los Alamos, and that’s where he stayed. He earned his master’s degree in mathematics from the University of New Mexico in 1976.
Balancing physics and engineering
In his undergraduate studies at CU, Wall had been fascinated with nuclear physics. As he learned in his second summer at LANL, and through the span of his five decades of work there, all areas of physics are involved in designing nuclear weapons—not just nuclear physics.
It’s a little difficult to describe what his work has entailed because the bulk of it is classified (Wall has a Q security clearance, the equivalent of top secret), “but the idea is that there is a requirement from the Department of Defense for some new weapon to go on some new delivery system and they set requirements for what they want,” Wall explains. “We take those requirements and put together ideas for what kind of device will meet them.
“Then, there’s a lot of physics design and engineering design to put together a device. Then, there’s a lot of testing of the function of the device, and at least until 1992 (when LANL conducted its last underground test at the Nevada Test Site), we’d go out to Nevada and do underground tests to verify that what we designed will work.”
On his first test at the Nevada Test Site, Wall was a junior member of the design team and had been tasked with writing a pre-shot report for a particular nuclear test his team had been working on. When it came time to do the test in Nevada, “I was on the spot having to say how well it was going to work,” he says. “As a junior member of the team, that was a lot of responsibility.”
Over the years, there were designs that didn’t work the way they were supposed to, but failures are also part of scientific learning, Wall says. As computer technology advanced, the LANL nuclear design group grew its capacities—using computer design calculations to look at variations and uncertainties. Plus, every design went through a battery of internal peer review and sometimes even inter-lab peer review with other national laboratories.
“The internal peer review was pretty intense, so that by the time we got to fielding tests in Nevada, we were reasonably confident that the design was sound,” Wall says.
“In this work, there’s physics and there’s engineering. We can design things in the computer, but then engineers have to figure out how to build it. It’s a give and take between the computer design and what can actually be built.
“The piece we do is called physics design, and we use all the different areas of physics that feed into the function of a nuclear weapon—codes, high explosives, hydrodynamics, material properties. Then, the design that gets finalized also has to meet requirements for being transported and actually being put on a delivery system, it has to meet environmental requirements. So, those are requirements we have to meet as well.”
Still learning
Though Wall technically retired in 2018, he still works half-time when he and his wife aren’t traveling. In 2005, he was named a laboratory fellow in recognition of special achievement, so now his title is lab associate fellow. One of the things he relishes most in his position now is mentoring the next generation of scientists.
“Gary’s commitment to mentoring the next generation of nuclear weapons scientists is just as—if not more—impressive than his long list of accomplishments,” Bob Webster, deputy laboratory director for weapons at LANL, said in a statement about the award.
“Los Alamos Laboratory has been a wonderful place to learn to be a scientist,” Wall says. “The lab does a lot beyond weapons, so there’s lots of opportunity to focus on various aspects of physics and fielding experiments that focus on different parts of physics. It’s a place where I’m still learning.”
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