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Cook's F-glider, backward velocity -c/9

Cook remarks that the F glider can be triggered from an A-C collision, the details of which are shown in Section 3.2.2.

Figure 2.29: The lackadasical F glider, which moves 4 left in 36 generations, for a velocity of -1/9 c. Left: the unit cell, expressed with T tiles. Right: presentation with S tiles, showing the different approach aspects. F gliders can be overpacked just as well as EBar gliders, but no such arrangement can arise from natural evolution.
\put(0,10){\epsfxsize = 140pt \...
...put(200,0){\epsfxsize = 150pt \epsffile{hfproach.eps}}

One period of an F glider occupies six ether files on the left, such as would be used in the approach of an A glider. However, it occupies only four files on the right, the path along which a B would approach. The difference is due, of course, to the differences in velocity between A's and B's, given that their orientations relative to the ether are different.

Jose Manuel Gomez Soto 2002-01-31