[FOM] Undecidability in geometry

[José Félix Costa]

Dear Fred,

In fact you can build up an abstract computer using a ruler and a compass
(as types of commands). Some Euclidean proofs turn to be programs for this
abstract computer. I will ask to my former student Francisco to send you a
draft of a paper on this matters.

Thanks,

Felix

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J. Felix Costa
Departamento de Matematica
Instituto Superior Tecnico
Av. Rovisco Pais, 1049-001 Lisboa, PORTUGAL
tel:      351 - 21 - 841 71 45
fax:     351 - 21 - 841 75 98
e-mail:   fgc at math.ist.utl.pt
www:    http://fgc.math.ist.utl.pt/jfc.htm
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