by Rqia May 17, 2022
Get the Sigmamug. A sigma algebra (or σ-algebra) is to set algebras what sigma males are to males. The Borel hierarchy (the analog of the male hierarchy) is not a σ-algebra at any countable rank; instead the σ-algebra has the largest possible rank -- ω_1, the least uncountable ordinal (under suitable conditions e.g. the Polish space is uncountable. This is known as the non-collapse of the Borel hierarchy).
A σ-algebra is closed under countable union, countable intersection, and relative complement. This means σ-algebras arise naturally in the study of measure theory, where the measurable sets form a σ-algebra.
A σ-algebra is closed under countable union, countable intersection, and relative complement. This means σ-algebras arise naturally in the study of measure theory, where the measurable sets form a σ-algebra.
The algebra of Lebesgue-measurable subsets of R (i.e. the sets of real numbers with a well-defined "length", which is possibly infinity) form a sigma algebra.
by sigma_algebra_grindset June 5, 2022
Get the sigma algebramug. by Tyler durden2333 August 12, 2022
Get the None Based Sigmamug. by Rocket0203 May 20, 2024
Get the Sigmamug. 
by Spiritwolf8 May 30, 2024
Get the Erm, what the sigmamug. by YEEHAWBRIDGES July 4, 2024
Get the Erm what the sigma?mug.