About

Krystal Lynn Tronboll

I started in theoretical mathematics at San Diego State, then moved into computational population genetics. My master's work mapped the genomes of Channel Island slender salamanders — collecting samples in the field, running PCRs in the lab, modeling the results against the tectonic history of Southern California and northern Baja. What the data said, in the end, is that the Channel Island populations are genetically pure descendants of a lineage that was cut off when the land shifted. The mathematics matched the geology, and the geology matched what the animals had been doing on their own for millions of years.

Before and during graduate school I taught in the cadaver lab at SDSU for ten semesters. Later I was an adjunct professor at the University of San Diego, where I built and taught the Evolutionary Biology curriculum. I was a field biologist for the National Park Service at Cabrillo. I homeschooled three children all the way to college readiness — and past. My eldest started at UCSD at sixteen and finished a degree in computer engineering with a minor in EE; my middle became a technologist and educator; my youngest has circumnavigated the globe twice, worked at a sea turtle preserve in Panama, and ridden horseback across the Mongolian Steppes.

Now I live in a desert in Ranchita, California. I run an animal sanctuary with my husband. And I write.

The writing is investigative. The through-line is not the animals or the desert or the family, though all of those are in it. The through-line is mathematics — specifically, what happens when mathematics is given institutional authority. I was trained to build models. I know what it takes to build one that reflects reality, and I know what it takes to build one that reflects a budget, a policy, or a comforting story.

Most of what governs modern life is the second kind. Clinical risk scores, eligibility cutoffs, maternal-mortality definitions, calibration curves on medical devices, categorization systems for cause of death — these are not neutral descriptions of the world. They are decisions. Someone chose what to count and what to leave out. Someone chose the time window and the denominator and the category boundaries. Those choices ripple through lives. And in almost every case I've investigated so far, the people whose lives are shaped most by the choice had no part in making it.

Maths Casualtiesis the long project. It proceeds case by case: a definition that dissolved a question, a proxy that hid a population, an algorithm whose optimization target betrayed its stated purpose. I write about historical cases (Galois, Ramanujan) to teach the pattern without contemporary political interference, and modern cases (the Optum risk algorithm, pulse oximeter calibration) to show that the pattern is not historical. Future sections will extend the project to my arc through academia, the sanctuary years, the homeschooling curriculum I built, and a series of books I'm writing — including Wisdom in the Margins: Professor Harold's Guide to the Grammar of Life, whose central character is a turkey.

I read technical documents the way an adversary reads a brief. I don't defer to credentials, and I don't extend charity to claims I can check. I try to be explicit about what I know, what I'm inferring, and what I don't yet. When I get something wrong, I want to hear about it — which is why there's an address for correspondence at the bottom of every case, and why my open questions are published as a register rather than hidden until they're answered.

— Krystal Lynn Tronboll