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Timeline for Convex hull of total orders

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Aug 12, 2014 at 2:50 comment added Lev Borisov I have a feeling that the number of facets of the total order polytope grows faster than a polynomial in $n$. As a result, the polytope can not be described by relations with a bounded set of indices.
S Aug 11, 2014 at 19:52 history suggested Mostafa - Free Palestine CC BY-SA 3.0
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S Aug 11, 2014 at 19:52
Aug 11, 2014 at 18:55 vote accept Mostafa - Free Palestine
Aug 11, 2014 at 18:54 vote accept Mostafa - Free Palestine
Aug 11, 2014 at 18:54
Aug 11, 2014 at 18:49 history bounty ended Per Alexandersson
Aug 11, 2014 at 18:41 comment added Per Alexandersson @EmilJeřábek: Good question! I feel this is related to the Birkhoff polytope, and also the convex hull of all Alternating Sign matrices of a fixed size. There is an article by J. Striker, giving the inequalities/equalities for the latter case, it is not a trivial task. So it might be that the inequalities for partial orders can be tricky to find. Perhaps some actual experimentation in Sage is in order...
Aug 11, 2014 at 18:36 comment added Emil Jeřábek Nice! The inequalities are valid for any partial order if we put $w_{ij}=0$ when $i,j$ are incomparable, and your example shows that some partial orders are not in the convex hull of total orders. A natural follow-up question is then whether the inequalities describe the convex hull of partial orders.
Aug 11, 2014 at 18:35 history edited David E Speyer CC BY-SA 3.0
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Aug 11, 2014 at 18:22 history edited David E Speyer CC BY-SA 3.0
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Aug 11, 2014 at 18:08 history undeleted David E Speyer
Aug 11, 2014 at 18:08 history edited David E Speyer CC BY-SA 3.0
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Aug 11, 2014 at 16:31 history deleted David E Speyer via Vote
Aug 11, 2014 at 16:30 history answered David E Speyer CC BY-SA 3.0