Michael Wilson 400 words 16 Colchester Avenue Burlington, Vermont 05405 Phone: 802-656-4326. Fax: 802-656-2552. Email: wilson@math.uvm.edu. THREE THEORIES ABOUT THE MILLENNIUM PROBLEM By now, most of us have heard of the Millennium Problem, or Y2K: the programming glitch that will prevent many computers from recognizing dates after the year 1999. What will happen to the computers, and to the systems they control, when their calendars click over to "00"? Will power grids shut down? Phone networks collapse? Businesses fail? Even the experts disagree. I propose three theories. I call the first theory, "Aux armes, citoyens!" The alien invasion of Earth will begin in the early hours of January 1, 2000. Three independent lines of reasoning support this conclusion. 1. All early warnings of the approaching attack fleet will be dismissed as "millennium glitches." 2. Even when the danger is recognized (too late!), it will be impossible to mount an effective defense, since all of Earth's weapon systems will be down with the Y2K flu. 3. Who is responsible for the Y2K bug, anyway? Computer programmers in the 1960's, that's who. Does anybody seriously believe that those guys were human? They said they were storing dates in two-digit form to save memory: a likely story! Theory number two: "Da capo." At the stroke of midnight (Greenwich Mean Time), on December 31, 1999, the entire universe will be reset to January 1, 1900. The history of the Twentieth Century will be erased, to be lived again. Spandex and sport-utes, along with most of the people who use them, will vanish, to be replaced by corsets, Stanley Steamers, and horses. Not every trace of the current Twentieth Century will disappear. Random artifacts will survive to challenge the ingenuity of late-Victorian man. Since this is certain to happen, it must have happened before---and before that---and before that---possibly hundreds of times. So, the next time you see a compact disk being used as a reflector for a kerosene lamp, an aquarium made from a thousand-year-old picture tube, or an armchair's leather upholstery tacked down with transistors, do not say---do not even think---"Oh, how quaint!" Theory number three: "Harmonic convergence." It is most likely that both of the preceding theories have some truth, and that the aliens, in planting the Millennium Bug, have unwittingly sealed the doom of their invasion plot. What delicious irony! On that fateful New Year's Eve, as the Imperial Expeditionary Fleet crosses the orbit of Mars, a temporal shock wave from Earth will wipe it out of existence, and hurl the Galactic Empire a century back in time!