Harry Soodak (1920–2008): Architect of Reactor Physics and Master of Classical Mechanics
Harry Soodak was a central figure in the mid-20th-century transformation of physics, transitioning from the secretive laboratories of the Manhattan Project to the lecture halls of the City College of New York (CCNY). A theoretical physicist of remarkable range, Soodak’s work spanned the foundational mathematics of nuclear reactors, the whimsical physics of spinning tops, and the complex thermodynamic rhythms of biological systems.
1. Biography: From the Bronx to Oak Ridge
Harry Soodak was born on December 24, 1920, in New York City. A product of the city’s rigorous public education system, he attended the City College of New York (CCNY), graduating with a B.S. in 1940. He then moved to Duke University for his graduate studies, earning his Ph.D. in 1944.
His doctoral research was interrupted by the exigencies of World War II. Soodak was recruited into the Manhattan Project, where he worked at the Clinton Laboratories (now Oak Ridge National Laboratory) in Tennessee. It was here that he worked under the legendary Eugene Wigner, the future Nobel laureate often called the "father of nuclear engineering." Soodak was part of the elite group of theorists tasked with calculating how to sustain and control a nuclear chain reaction.
In 1949, Soodak returned to his alma mater, CCNY, joining the faculty of the Physics Department. He remained there for the rest of his career, serving as a Professor of Physics for over four decades until his retirement in 1991, after which he continued as Professor Emeritus until his death in 2008.
2. Major Contributions: Piles, Tops, and Homeokinetics
Soodak’s intellectual contributions can be divided into three distinct phases:
The Mathematics of Nuclear Reactors
During and immediately after the war, Soodak helped develop "Pile Theory." In the 1940s, nuclear reactors were called "piles" (literally piles of graphite and uranium). Soodak developed the mathematical frameworks for neutron diffusion and slowing-down theory, which allowed engineers to predict the behavior of a reactor before it was built. His work provided the essential bridge between pure nuclear physics and practical nuclear engineering.
Classical Mechanics and the "Tippe Top"
Soodak possessed a rare ability to find profound physics in everyday objects. He became a world authority on the "Tippe Top"—a mushroom-shaped toy that, when spun, mysteriously flips over to spin on its stem. While it seems like a simple toy, the mathematics of its inversion involves complex friction-induced instabilities. Soodak’s rigorous analysis of the mechanics of rolling and sliding objects remains a benchmark in classical mechanics pedagogy.
Homeokinetics
In his later career, Soodak collaborated with Arthur Iberall to develop "Homeokinetics," a branch of physics that applies the laws of thermodynamics to complex, self-organizing systems—including biological organisms and social structures. They proposed that life is maintained not by static equilibrium, but by a series of rhythmic, cyclic processes (oscillators) that keep an organism within a viable operating range.
3. Notable Publications
- Elementary Pile Theory (1950): Co-authored with Edward Campbell, this was one of the first textbooks to declassify and explain the physics of nuclear reactors. It became the "bible" for the first generation of nuclear engineers.
- Reactor Handbook (1962): Soodak served as the editor for the "Physics" volume of this massive AEC (Atomic Energy Commission) project, which served as the definitive reference for the global nuclear industry for decades.
- "A Geometric Theory of the Tippe Top" (Am. J. Phys., 1976): A classic paper that provided a clear, geometric explanation for a phenomenon that had puzzled physicists for a century.
- "Homeokinetics: A Physical Descriptor for Complex Systems" (Science, 1978): Co-authored with Iberall, this paper introduced the broader scientific community to the idea of using physics to model the "internal government" of living things.
4. Awards & Recognition
While Soodak did not seek the limelight, his peers recognized his profound influence:
- Fellow of the American Physical Society (APS): Elected for his contributions to nuclear reactor theory.
- The Townsend Harris Medal (1984): Awarded by the CCNY Alumni Association for outstanding postgraduate achievement.
- Distinguished Teacher Awards: Soodak was repeatedly honored by CCNY for his pedagogy. He was known for his "Socratic" method, often answering a student's question with a more profound question that led them to the answer.
5. Impact & Legacy
Soodak’s primary legacy is twofold: the birth of nuclear engineering and the "Golden Age" of physics at CCNY.
His work at Oak Ridge helped transition nuclear energy from a weapon of war to a source of civilian power. More personally, he was a pillar of the CCNY Physics Department during an era when it produced more future Nobel laureates than almost any other institution. Soodak was the "physicist’s physicist"—the man other professors went to when they were stuck on a mathematical problem.
His influence lives on through the Harry Soodak Scholarship and Fund, established at CCNY to support promising physics students, ensuring that his commitment to accessible, high-level education continues.
6. Collaborations
- Eugene Wigner: Soodak’s mentor during the Manhattan Project. Wigner’s influence is evident in Soodak’s rigorous, symmetry-based approach to physical problems.
- Arthur Iberall: A long-term partnership that pushed Soodak into the realms of biophysics and systems science.
- The CCNY Faculty: He worked alongside greats like Mark Zemansky (thermodynamics) and Herman Z. Cummins, contributing to a department that was a powerhouse of mid-century theoretical research.
7. Lesser-Known Facts
- The Slinky Expert: Soodak was fascinated by the physics of the "Slinky" toy. He famously analyzed the "suspended Slinky" problem—noting that when a stretched Slinky is dropped, the bottom of the coil remains perfectly stationary in mid-air until the collapsing top of the coil reaches it.
- A "Human Calculator": Colleagues recalled that Soodak could perform complex spherical harmonic calculations in his head, a skill honed in the days before digital computers when "computers" were people with slide rules.
- The Blackboard Artist: He was known for his impeccably neat blackboard work. Students often remarked that his lectures were so logically structured that they felt like they were watching a mathematical proof unfold in real-time.
- Late-Night Philosophy: Soodak was known to engage in marathon sessions at CCNY, staying late into the night to discuss the philosophical implications of thermodynamics and the arrow of time with students and faculty alike.