Timeline for Conservativity of language extension
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 24, 2018 at 20:30 | vote | accept | Floris van Doorn | ||
| Nov 24, 2018 at 7:16 | answer | added | Emil Jeřábek | timeline score: 4 | |
| Nov 24, 2018 at 5:55 | comment | added | Marc Hoyois | There is an elementary proof of this on page 14 of www-bcf.usc.edu/~hoyois/papers/logic.pdf (an old undegraduate essay of mine). | |
| Nov 24, 2018 at 1:34 | comment | added | Floris van Doorn | Yes, it seems related to the Craig Interpolation Theorem. A formulation of Craig Interpolation Theorem I know is that if $\Gamma$ proves $\varphi$, then there is a formula $\psi$ which contains only constants/function symbols/relation symbols which occur in both $\Gamma$ and $\varphi$ such that $\Gamma\vdash\psi$ and $\psi\vdash\varphi$. However, since these new proof trees are still in $L'$, I don't know if that actually helps. | |
| Nov 24, 2018 at 1:23 | comment | added | Gerhard Paseman | Perhaps the Craig Interpolation Theorem would help? Or are you looking for prerequisites in order to prove CIT? Gerhard "Taking An Approximate Stab Here" Paseman, 2018.11.23. | |
| Nov 24, 2018 at 1:15 | review | First posts | |||
| Nov 24, 2018 at 7:54 | |||||
| Nov 24, 2018 at 1:14 | history | asked | Floris van Doorn | CC BY-SA 4.0 |