Biometric systems are currently used by intelligence and security services to detect criminals. In Level of Confidence (2015), Rafael Lozano-Hemmer’s work was used a similar system so that the public could recognize themselves in one of the 43 missing students from Ayotzinapa, Guerrero, México. The appearance of the students, who mostly had indigenous features, leads one to wonder whether their disappearance has to do with the racist and classist idea of eliminating from the earth everything that is different, opposite or singular. In 2018, Level of Confidence was presented at the 12th Symposium of Visual Arts of the Institute of Arts of the Autonomous University of the State of Hidalgo, which gave rise to the community’s commentary and reflection on this crime against humanity and the role of the Mexican State.
An embedding of arbitrary Heyting algebra H into a reduct from the variety of Kuznetsov-Muravitsky algebras is constructed. An algebraic proof is given that this reduct belongs to the variety of Heyting algebras generated by H.
We present a rooted hypersequent calculus for modal propositional logic S5. We show that all rules of this calculus are invertible and that the rules of weakening, contraction, and cut are admissible. Soundness and completeness are established as well.
We prove that $\ omega $-categorical dp-minimal groups are nilpotent-by-finite. We also show that in dp-minimal definably amenable groups, f-generic global types are strongly f-generic.
We prove that the automorphism group of a Fraïssé structure M equipped with a notion of stationary independence is universal for the class of automorphism groups of substructures of M. Furthermore, we show that this applies to certain homogeneous n-gons.
Using Kripke models, it is shown that CZF does not prove Power Set, and that CZF with Subset Collection substituted by Exponentiation does not prove Subset Collection.
We give a characterization of the validity of the distributive law in a solid. There exists equivalence between the characterization and the modified axiom of distibutivity valid in a solid.
In this thesis, we will look at some known and some previously uninvestigated notions of effective undecidability. We try to discover how far we can stretch effective undecidability in the hope to get a more tractable solution to Post's problem, than that of Friedberg and Muchnik.
In this paper, we will generalize the definition of partially random or complex reals, and then show the duality of random and complex, i.e., a generalized version of Levin-Schnorr's theorem. We also study randomness from the view point of arithmetic using the relativization to a complete $Π^0_1$-class.
We augment LP with a strong conditional operator, to yield a logic we call "strong LP," or LP=>. The resulting logic can speak of consistency in more discriminating ways, but introduces new possibilities for trivializing paradoxes.
We give a sufficient condition that implies that SNr_nCA_{n+k}, n\geq 3, k\geq 3 (both finite)is not closed under completions. We compare this condition to existing results in literature.
I give a proof of the confluence of combinatory strong reduction that does not use the one of lambda-calculus. I also give simple and direct proofs of a standardization theorem for this reduction and the strong normalization of simply typed terms.
We continue the investigation of Gregory trees and the Cantor Tree Property carried out by Hart and Kunen. We produce models of MA with the Continuum arbitrarily large in which there are Gregory trees, and in which there are no Gregory trees.
We show that there are semi-Cohen Boolean algebras which cannot be completely embedded into Cohen Boolean algebras. Using the ideas from this proof, we give a simpler argument for a theorem of S. Koppelberg and S. Shelah, stating that there are complete subalgebras of Cohen algebras which are not Cohen themselves.
Shelah's own proof to his recent polarized partition theorem involving a singular strong limit that violates the GCH is presented. The proof is slightly re-arranges so that no use of the ideal I[λ] is made. The proof should be readabel to any student with knowledge of set theory.
We deal with an iteration theorem of forcing notion with a kind of countable support of nice enough forcing notion which is proper aleph_2-c.c. forcing notions. We then look at some special cases (Q_D 's preceded by random forcing).