Refreshments will be served at 3:30 pm in Mudd 412A.

Abstract: When you push a phone key\, two tones are sent. How does the exchange decipher these tones to know which number you pushed? When you turn on your FM radio\, how does it know which station to choose? Filters.

This talk will look at some filters and the mathematics used to design those filters: calculus (the Fourier Transform\, the Laplace Transform)\, number theory (continued fractions)\, linear algebra (2×2 matrices)\, polynomials\, rational functions\, and complex numbers.

And for the students who remember me\, they know there will be pretty and interesting graphs and electronic gadgetry.

URL;VALUE=URI://www.colby.edu/events/viewevent?rID=67907&bID=557975 SUMMARY:Which Key Made That Touchtone? DTSTART;TZID=America/New_York:20091207T160000 END:VEVENT END:VCALENDAR