The Mad-Stone.

Mad spectra

The mad spectrum is the set of all cardinalities of infinite maximal almost disjoint families on ω. We treat the problem to characterize those sets A which, in some forcing extension of the universe, can be the mad spectrum. We give a complete solution to this problem under the assumption θ = θ, where θ = min(A). §0. Introduction. Recall that A ⊆ [ω] is called almost disjoint (a. d. for short),...

MAD families and the rationals

Rational numbers are used to classify maximal almost disjoint (MAD) families of subsets of the integers. Combinatorial characterization of indestructibility of MAD families by the likes of Cohen, Miller and Sacks forcings are presented. Using these it is shown that Sacks indestructible MAD family exists in ZFC and that b = c implies that there is a Cohen indestructible MAD family. It follows th...

Very Mad Families

The notion of very mad family is a strengthening of the notion of mad family of functions. Here we show existence of very mad families in different contexts.

On healing the epidemic of MAD.

Mad dogs: the new rabies plague

letters reproduced here, the book's main focus is on the work of Rayer: five chapters are devoted to meticulous analysis of his contributions to nineteenth-century medical science. It is an impressive collection of observations on a wide variety of subjects: from his doctoral thesis on the history of morbid anatomy to the observations on human and animal teratology. His pioneering studies in co...