Author Archives: jgl

This month, we will start to do Exercise V-5.25 of the red book (Continuous Lattices and Domains), which gives an example of a core-compact, not locally compact space.  That is pretty hard to obtain, really.  This month, we will do … Continue reading →

Let me first wish you a Merry Christmas, and since I will not post again next week, a Happy New Year 2019 as well.  I have no specific present this year, sorry… This month’s post is about a few thoughts … Continue reading →

Last time, we embarked on proving that the projective limit of a projective system of compact sober (resp., and non-empty) spaces is compact and sober (resp., and non-empty), a theorem that Fujiwara and Kato call Steenrod’s Theorem.  However, instead, we … Continue reading →

Last time, I explained some of the strange things that happen with projective limits of topological spaces: they can be empty, even if all the spaces in the given projective system are non-empty and all bonding maps are surjective, and … Continue reading →

This month, let me investigate projective limits of topological spaces.  That is an area of mathematics that is fraught with pitfalls, and I will describe a number of odd situations that can occur in that domain.  You will have to … Continue reading →

I thought I would devote my blog this month to the Domains workshop, but a sudden health problem prevented me to go there.  Instead, I will talk about a curious alternative to Stone duality, which, instead of an adjunction between Top … Continue reading →

Let us continue last month’s story.  We had define various structures of convergence spaces on a dcpo, which were all admissible in the sense that their topological modification is the Scott topology.  We shall see that equipping dcpos with their … Continue reading →

Every dcpo can be seen as a topological space, once we equip it with the Scott topology. And every topological space can be seen as a convergence space, so every dcpo can be seen as a convergence space.  In 2003, Reinhold … Continue reading →

Only a short post this month: I would like to explain Lawson’s construction of an FS-domain that is not known to be an RB-domain. Roughly speaking, this is the domain of closed discs of the under with reverse inclusion, and … Continue reading →