Timeline for "Effective gaps" in the c.e. degrees
Current License: CC BY-SA 4.0
5 events
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Apr 28 at 19:49 | history | edited | Noah Schweber | CC BY-SA 4.0 |
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Apr 27 at 20:10 | comment | added | Noah Schweber | @StevenStadnicki Certainly it's easy to embed $\omega+\omega^*$ in any interval, just using Sacks density. The issue is the second bulletpoint, the "unfillability" - put another way, I see no easy way to prevent an embedding $f:\omega+\omega^*\rightarrow\mathcal{R}$ from extending to an embedding $g: \omega+1+\omega^*\rightarrow\mathcal{R}$. (Here $\mathcal{R}$ is the set of c.e. Turing degrees.) | |
Apr 27 at 20:05 | comment | added | Steven Stadnicki | I suspect you might be able to modify the proof of the special case (of the theorem that all countable linear orders are embeddable in the c.e. degrees) that $\omega+\omega^*$ is embeddable to at least show that effective gaps exist. | |
Apr 27 at 19:11 | history | edited | Noah Schweber | CC BY-SA 4.0 |
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Apr 27 at 18:57 | history | asked | Noah Schweber | CC BY-SA 4.0 |