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This is a blog where a professor from Northeastern University's Math department posts mathematical comments on the television show "Numb3rs". To comment, write to bridger@neu.edu.
Unique visitors since 6/14/2005:
October 31, 2009
Last night's episode, as you may have noticed, had no mathematics in it. I was hoping that it would at least be exciting after a spooky beginning, but no -- it petered out into the usual foot and car chases. The one moment of tension, when Charlie and Floyd (see below) are confronted by the death-ray drone, ends with the plane inexplicably simply flying away... continued »
October 24, 2009
Charlie claims that he can create a "sound signature" for a car that identifies that car uniquely -- or nearly uniquely. I'm not entirely convinced, because the sound a car emits varies a lot with conditions: the speed of the engine, the incline of the road, the condition of the muffler etc. It may even depend on the ambient temperature and the kind of gas. However, I am not an automotive expert, so I won't deny the possibility... continued »
October 22, 2009
The most interesting math on last Friday's show involved Charlie's analysis of the drying agent or desiccant (silica gel is probably the most common one). Charlie points out that the way the desiccant works is not simply linear. This means the it is not true, for example, that it takes three times the time to remove three times the amount of water... continued »
October 10, 2009
Last night's episode was pretty much a loser.
There was almost no mathematics, and what there was contained a careless mistake, caught by, among others, blog readers P.J. Campbell and J. Simonoff. In describing the "game" of Russian Roulette, Larry says the following: "The chances of the gun going off are 1 out of 6, or 6-to-1 odds." The probability is indeed 1 out of 6, since there is exactly 1 bullet in one of the 6 chambers. However, the odds are 1 to 5: 1 shot to 5 clicks... continued »
October 5, 2009
Charlie uses laser imaging to reconstruct the scene of the shootout central to last Friday's episode. Laser imaging is in many ways similar in principle to radar (see the blog Radar ).
The basic idea of both is to bounce a signal, traveling at the speed of light, off an object, and time how long it takes the signal to return... continued »