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1 answer
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Is there anyway to formulate the Alexandrov topology algebraically?

One knows that the Alexandrov topology on a preordered set is the finest topology that induces the same [specialization] preorder on the set. Given this, one finds a one-to-one correspondence between ...
Bastam Tajik's user avatar
2 votes
1 answer
158 views

Adjoints of the interval topology functor

Given a poset $(P,\leq)$ the interval topology $\tau_i(P)$ on $P$ is generated by $$\{P\setminus{\downarrow x} : x\in P\} \cup \{P\setminus{\uparrow x} : x\in P\},$$ where $\downarrow x = \{y\in P: y\...
Dominic van der Zypen's user avatar
3 votes
0 answers
130 views

Duality for continuous lattices based on [0, 1]

A continuous lattice may be defined as a complete lattice in which arbitrary meets distribute over directed joins. A continuous lattice is naturally regarded as an algebraic structure where the ...
Ronnie's user avatar
  • 133
2 votes
0 answers
177 views

A categorical analogue of Debreu's independent factors theorem

Background A major question in Decision Theory is that of the cardinal meaning of a utility function. That is, given a set $X$, a utility function $u:X\rightarrow \mathbb{R}$ represents the choices ...
Henrique de Oliveira's user avatar
8 votes
1 answer
599 views

What should the morphisms in the Category of Directed Sets be?

Directed sets are defined to be sets equipped with a preorder that admit (finitary) upper bounds e.g. pairs $(D, \preceq)$ such that $\forall p,q \in D$ there exists $r \in D$ such that $p \preceq r$ ...
Tyler Bryson's user avatar
17 votes
3 answers
1k views

Is there a natural measurable structure on the $\sigma$-algebra of a measurable space?

Let $(X, \Sigma)$ denote a measurable space. Is there a non-trivial $\sigma$-algebra $\Sigma^1$ of subsets of $\Sigma$ so that $(\Sigma, \Sigma^1)$ is also a measurable space? Here is one natural ...
Tom LaGatta's user avatar
  • 8,322