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Timeline for Embedding of graph classes

Current License: CC BY-SA 4.0

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Feb 26, 2022 at 10:24 comment added Ben Tom In one of the comments above, I wrote about the decidability of $A$ and $B$.
Feb 26, 2022 at 8:35 comment added 喻 良 How about $A[n]=\emptyset$ if the $n$-th Turing machine halts with input $n$, and $A[n]$is not empty otherwise. Then even for $(A, COM)$, the domain is undecidable.
Feb 25, 2022 at 12:28 comment added Ben Tom This is not a problem because the domain of this function is decidable.
Feb 25, 2022 at 11:15 comment added 喻 良 This is not even a total function. For example, what if $A[n]$ is empty for some $n$?
Feb 23, 2022 at 16:48 comment added Ben Tom @LeechLattice , what if for any $G \in A[n]$ there is no $H \in B$ such that $G$ embeds in $H$? How does the machine know when to stop?
Feb 23, 2022 at 16:39 comment added LeechLattice The machine can just enumerate all $n$-vertex graphs to find graphs that can play the role for $G$, and it can also enumerate graphs by increasing order of vertices to find which graph can play the role of $H$.
Feb 23, 2022 at 16:32 comment added Ben Tom @LeechLattice , I need the machine to be able to recognize both $A$ and $B$. The fact that max does not affect computability is not entirely clear, because the machine needs to know which graphs from $A[n]$ it can take to test for the maximum.
Feb 23, 2022 at 16:18 comment added LeechLattice How is the set $B$ given? The $\text{max}$ part is just finite and does not affect computability.
Feb 23, 2022 at 13:07 history asked Ben Tom CC BY-SA 4.0