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Timeline for Free monoids on posets

Current License: CC BY-SA 4.0

26 events
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Apr 21, 2021 at 22:16 comment added Benjamin Steinberg OK. So if S is not totally ordered we can't first make the order total.
Apr 21, 2021 at 18:44 comment added Jeff Strom @BenjaminSteinberg I definitely want the order on $S$ to remain unchanged.
Apr 21, 2021 at 16:06 comment added Benjamin Steinberg Does the order on F(S) have to restrict to the original order on S or can it extend the order?
Apr 21, 2021 at 16:04 comment added Benjamin Steinberg I don't know a description of that space. It might be massive
Apr 21, 2021 at 15:58 comment added Jeff Strom @BenjaminSteinberg Sure! If you make it an answer, I'll certainly upvote it.
Apr 21, 2021 at 15:53 comment added Benjamin Steinberg The compatible partial orders on the free monoid form a compact totally disconnected space and the space of such orders that agree with the original order on S is a closed subspace. If S is finite it is even clopen. Do you want a description of that space?
Apr 21, 2021 at 15:48 comment added Benjamin Steinberg This looks a bit like term orderings except that they often require total orders.
Apr 21, 2021 at 15:23 comment added Jeff Strom @SamHopkins Yes, that's right.
Apr 21, 2021 at 15:22 history edited Jeff Strom CC BY-SA 4.0
added 280 characters in body
Apr 21, 2021 at 15:19 comment added Sam Hopkins I see, thanks. So as Benjamin Steinberg notes you are not really talking about a single construction.
Apr 21, 2021 at 15:19 comment added Jeff Strom @SamHopkins I said if and did not mean only if -- clarified now.
Apr 21, 2021 at 15:18 history edited Jeff Strom CC BY-SA 4.0
more clarification on inequality
Apr 21, 2021 at 15:15 comment added Benjamin Steinberg I thought you were defining the order that way. Then your question is ambiguous since there are many orderings extending the ordering on S.
Apr 21, 2021 at 15:10 comment added Jeff Strom @BenjaminSteinberg I don't think so. For example, say $S = \{ x,y,z\}$ with $x< z$ and $y< z$. Then in the extended partial order, it can happen that $xy< z$ or not.
Apr 21, 2021 at 15:01 history edited YCor CC BY-SA 4.0
fixed typo
Apr 21, 2021 at 15:01 comment added Benjamin Steinberg This seems to just be the disjoint union of the product orders on the sets $S^n$ and then observing that concatenation obviously respects this.
Apr 21, 2021 at 14:56 comment added Benjamin Steinberg Do you mean $s_i\leq t_i$?
Apr 21, 2021 at 14:55 comment added Sam Hopkins It seems that the poset you defined is just the disjoint union of $S^n$ over all $n\geq 0$; how much more could there be to say about it?
Apr 21, 2021 at 14:53 comment added Jeff Strom @BenjaminSteinberg It's like I've found a new gadget, and I'm looking for the instruction book. I don't specifically have in mind that left adjoint, but I'd be happy to read about it.
Apr 21, 2021 at 14:52 comment added Jeff Strom @SamHopkins No, it is genuinely free.
Apr 21, 2021 at 14:51 comment added Jeff Strom @YCor Clarified!
Apr 21, 2021 at 14:51 history edited Jeff Strom CC BY-SA 4.0
clarified order preservation
Apr 21, 2021 at 14:31 comment added Benjamin Steinberg Are you looking for a left adjoint to the forgetful functor from pomonoids to posets?
Apr 21, 2021 at 14:12 comment added Sam Hopkins Do you mean a quotient of the free monoid?
Apr 21, 2021 at 14:11 comment added YCor What do you mean by "multiplication respects the partial order"? the order is a priori on $S$, not on $F(S)$.
Apr 21, 2021 at 14:10 history asked Jeff Strom CC BY-SA 4.0