Activity for Prime Mover
Type | On... | Excerpt | Status | Date |
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Comment | Post #286572 |
Added as suggested (more) |
— | almost 3 years ago |
Edit | Post #286572 |
Post edited: added definition of entropic structure |
— | almost 3 years ago |
Edit | Post #286572 | Initial revision | — | almost 3 years ago |
Question | — |
Endomorphisms on an entropic structure whose pointwise product is the identity automorphism - entropic idempotent structure? Context: self-study from Warner's "Modern Algebra (1965): Exercise 16.27. >Let (more) |
— | almost 3 years ago |
Edit | Post #286571 |
Post edited: |
— | almost 3 years ago |
Edit | Post #286571 | Initial revision | — | almost 3 years ago |
Answer | — |
A: In "if and only if" proofs, why's 1 direction easier to prove than the other? Here's a good one: Every set is well-orderable iff the Axiom of Choice holds. It is quite challenging to prove that the Axiom of Choice implies that every set is well-orderable. Smullyan and Fitting build up to it in a focused but leisurely manner over the course of 3 chapters in their "Set Theory... (more) |
— | almost 3 years ago |