4 papers
math.HO2012
Todas as afirmações verdadeiras são demonstráveis
Jaime Gaspar
In this instructional exposition in Portuguese for the popularisation of mathematics, we state and prove the completeness theorem.
math.LO2012
Copies of classical logic in intuitionistic logic
Jaime Gaspar
Classical logic (the logic of non-constructive mathematics) is stronger than intuitionistic logic (the logic of constructive mathematics). Despite this, there are copies of classic…
math.HO2012
A theorem with constructive and non-constructive proofs
Jaime Gaspar
We present a very simple example of a theorem with constructive and non-constructive proofs: the equation c^2 x^2 - (c^2 + c)x + c = 0 has a solution.
math.LO2010
Negative translations not intuitionistically equivalent to the usual ones
Jaime Gaspar
We refute the conjecture that all negative translations are intuitionistically equivalent by giving two counterexamples. Then we characterise the negative translations intuitionist…