-- The Purest Light and a Resonance Hero – Ken Evenson (1932-2002) --
When travelers punch up their GPS coordinates they owe a debt of gratitude to an under sung hero who, alongside his colleagues and students, often toiled 18 hour days deep inside a laser laboratory lit only by the purest light in the universe.
Ken was an “Indiana Jones” of modern physics. While he may never have been called “Montana Ken,” such a name would describe a real life hero from Bozeman, Montana, whose extraordinary accomplishments in many ways surpass the fictional characters in cinematic thrillers like Raiders of the Lost Arc.
Indeed, there were some exciting real life moments shared by his wife Vera, one together with Ken in a canoe literally inches from the hundred-foot drop-off of Brazil’s largest waterfall. But, such outdoor exploits, of which Ken had many, pale in the light of an in-the-lab brilliance and courage that profoundly enriched the world.
Ken is one of few researchers and perhaps the only physicist to be twice listed in the Guinness Book of Records. The listings are not for jungle exploits but for his lab’s highest frequency measurement and their speed of light determination that made c many times more precise due to his pioneering work in laser resonance and metrology.
Then the meter-kilogram-second (mks) system of units underwent a redefinition largely because of Ken’s efforts. Thereafter, the speed of light c was set to 299,792,458ms-1. The meter was defined in terms of c, instead of the other way around since his time precision had so far trumped that for distance. Without such resonance precision, the Global Positioning System (GPS), the first large-scale wave space-time coordinate system, would not be possible.
Ken’s courage and persistence at the Time and Frequency Division of the Boulder Laboratories in the National Bureau of Standards (now the National Institute of Standards and Technology or NIST) are legendary as are his railings against boneheaded administrators who seemed bent on thwarting his best efforts. Undaunted, Ken’s lab painstakingly exploited the resonance properties of metal-insulator diodes, and succeeded in literally counting the waves of near-infrared radiation and eventually visible light itself.
Those who knew Ken miss him terribly. But, his indelible legacy resonates today as ultra-precise atomic and molecular wave and pulse quantum optics continue to advance and provide heretofore unimaginable capability. Our quality of life depends on their metrology through the Quality and Finesse of the resonant oscillators that are the heartbeats of our technology.
Before being taken by Lou Gehrig’s disease, Ken began ultra-precise laser spectroscopy of unusual molecules such as HO2, the radical cousin of the more common H2O. Like Ken, such radical molecules affect us as much or more than better known ones. But also like Ken, they toil in obscurity, illuminated only by the purest light in the universe.