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    Circular Polarization and the Search for Semi-Intelligent Life

    It took me a little while to wrap my head around circularly polarized light, or more specifically how this can be done "passively". Wikipedia didn't do much help until I found the article at Polarizer, if any of you were wondering how the new 3D movie technology works. My first question is...
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    Where do neutrinos go?

    Neutrinos have mass... insignificant mass, we are told, as their speed is so near that of light we can't even observe the difference. On the other hand, there are a lot of them. Every year the Sun produces something like half a tredecillion neutrinos, if my math is right. Depending on the mass...
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    Brain Teaser #98

    I heard this one a while back: A Hungarian community of married mathematicians has the following tradition: should any man determine that his wife cheated on him, he shall hang himself at noon. The townsfolk being rather introverted, there is little gossip except when there is an affair. In...
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    Brain Teaser #94

    Brain Thumper #8 The Pacific Proprietary Production Plant has the capacity to manufacture straight sections of miniature railroad track on two machines, each of which produces a specific length of track. For instance, suppose that the company had initially configured the machines to make...
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    Brain Teaser #93

    Brain Thumper #7 What is the greatest number of knights that can be placed on a chessboard such that no two pieces are in a position to attack each other? Please provide your solution.
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    Brain Teaser #92

    Brain Thumper #6 Find the smallest positive integer that does not evenly divide any Fibonacci number in the sequence starting 1, 1, 2, 3, 5, 8, 13, 21, etc.
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    Brain Teaser #91

    Brain Thumper #5 Five transit centers are evenly spaced near the perimeter of a small city. Any two transit centers are connected by exactly one route. Additionally, from each transit center there is one route that extends into the suburbs in the shape of a large colorful lollipop. The five...
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    Brain Teaser #89

    Brain Thumper #4 First some definitions. A bloc of voters is a group who cooperate to achieve their common goals. In other words, they have the same preferences and vote strategically, which means that they coordinate their votes so as to maximize the outcome. We will assume political party...
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    ReTurn Time - 3

    Brain Thumper #3 The apocryphal Mayan clock has two faces. The left face is divided into 13 equal sections partitioned by marks that include one pointing straight down. Each section is labeled with a number 1 to 13, starting with a dot at the very top and proceeding clockwise with three dots, a...
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    Brain Teaser #87

    Brain Thumper #2 Three reasonably thin ropes of more than sufficient length are specially made so that they connect seamlessly at the ends. One is red, one white, and one blue. They are floated in a large kiddie pool which is then drained for the following game. A person picks a location in...
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    Brain Teaser #84

    It's time to study ancient Laurasian civilization. Here's an important formula that may or may not look familiar: L = J'6oAL EL5J YCAQ JC5C 68oL -> 5'TYoA QELL |6T5 LLC5 J5dd i Some common numerical sequences are encoded below: J, d, E, o, Q, LL, Ld, L8, dQ, E2, 56, o8, J|2, JE8, T88...
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    Non-arbitrary units

    What units in the physical universe are not arbitrary? E.g. time (as measured in seconds and years) is arbitrary since it's based on the changing orbit of this little planet in some odd solar system on the edge of an insignificant galaxy. Atomic mass is arbitrary since it relies on which...