- expository
- math
- set-theory
- lolbvious

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### Silly proof of nonisomorphic uncountable linear orders using ordertypes of nonstandard models of arithmetic

All nonstandard models of arithmetic have ordertypes N+Zθ. None has ordertype N+ZR.

### Being reals of a model of set theory a special property

Proof that reals in a model of set theory have inner measure zero if they are not all the reals

### Three funny proofs of the existence of incomparable Turing degrees

Nuking incomparable mosquitoes with forcing, measure and category, and absoluteness

### A perfect set of not-eventually-equal reals

clarification on a remark by Greg Hjorth

### What's difficult about forcing?

An introductory overview of forcing, from the learner's perspective

### Well-ordering of the reals is not measurable

An example of a nonmeasurable set that occurs in logic