Math and statistics help explain the FBI's “missing scientists” cases

May 7, 2026

4 min read

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Math and statistics help explain the FBI's “missing scientists” cases

Statistical principles show you don’t need a nefarious plot to explain clusters of missing scientists and lab workers

By Faye Flam edited by Dan Vergano

J. Edgar Hoover FBI wall emblem on the side of the FBI Building.

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In April a writer friend e-mailed me a story from the U.K.-based tabloid Daily Mail—“Mystery surrounds death of NINTH scientist tied to US secrets as disturbing pattern grows”—with the comment, “and they’re just starting to notice?” But I didn’t see the pattern, even after reading it twice.

Now the FBI has launched an investigation, and the list has grown to 11 or maybe 12 people seemingly linked through their “mysterious” deaths or disappearances. Yet some simple statistical principles suggest any connection is likely an illusion.

One idea that comes in handy in cases like this is statistician David Hand’s “improbability principle.” Random numbers, words or distributions of events, he says, can appear to clump and cluster in patterns if you make the numbers big enough. And the missing scientist situation, he says, “is a case for the improbability principle.”

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The principle is rooted in what Hand and others have called the law of truly large numbers. In a series of trillions of random numbers, for example, a string of seven 7’s would be almost certain to show up. In a world of more than eight billion busy people, a few will bump into a neighbor traveling in a distant country, for example. The world has so many moving parts that extraordinary and even unheard-of things happen all the time.

It’s not even particularly improbable that of the thousands of Americans who disappear or are murdered every year, a few would include prominent scientists or people who’ve worked at large laboratories.

Hand says that a couple of errors that can make randomly occurring patterns look deceptively connected. One is the “near-enough” effect. This often shows up in surprising stories about repeat lottery winners when the definition of “win” is expanded to include people who won second or third prizes of relatively small value. Suddenly a double win doesn’t seem astronomically improbable at all.

In the missing scientist investigation, it helps to consider how the allegedly disturbing pattern was first identified. CNN ran a helpful story tracing the index case to the late Massachusetts Institute of Technology physicist Nuno Loureiro. He died on December 16 after being shot by the same person who had opened fire on a group of students at Brown University days earlier, killing two people. The shooter was soon identified as a former physics classmate thought to have been jealous of Loureiro’s success.

Elsewhere, however, people speculated that Loureiro was targeted because of his work in nuclear fusion. Fusion—uniting small atomic nuclei into larger ones—promises more abundant, cleaner energy once scientists perfect it. Some fusion research is connected to weapons, but Loureiro was part of a large network of scientists working on big experimental reactors and sharing ideas at meetings and in papers. If a breakthrough had motivated his murder, his colleagues should have known about it.

Were other fusion scientists being murdered? A writer named Jessica Reed Kraus noted that another scientist, Carl Grillmair, was shot at his home north of Los Angeles in February. Grillmair, however, was an astrophysicist who worked on observations of exoplanets—planets orbiting other stars in the galaxy.

Kraus wrote that both murdered scientists were “versed in planetary catastrophes.” What fusion and exoplanets have to do with planetary catastrophes is unclear, but for some, it’s near enough.

The victim list grew to a “NINTH” person, as the Daily Mail would have it, through another improbability principle error called the “look-elsewhere” effect, which was named by particle physicists to explain a hazard of attempting to interpret the debris they capture by smashing particles together in