Thomas Kahle
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 Sep 4 revised Graded-irreducible ideals are irreducible? expand a lot on different gradings. Sep 4 comment How can I include irreducibility in a Groebner basis calculation? And 3) The irreducibility is hard to model in this framework, but over an algebraically closed field there is of course the Nullstellensatz which can give infeasibility certificates. Sep 4 awarded Custodian Sep 4 comment How can I include irreducibility in a Groebner basis calculation? Two comments: 1) This depends very much on the field you want your solutions from. Real root finding for instance is a branch of real algebraic geometry. 2) Gröbner bases can't help you since you can't use them to decide if a single polynomial is irreducible. You need factorization algorithms and then 1) comes into play. Sep 4 reviewed Reviewed Help with notations from 2D to 3D FFT representations as 1D FFT Sep 3 answered Graded-irreducible ideals are irreducible? Aug 31 revised Is an irreducible ideal in $R$ also irreducible in $R[x]$? Streamline many small details, fix typos, make proof understandable to me. Aug 31 accepted Is an irreducible ideal in $R$ also irreducible in $R[x]$? Aug 31 comment Is an irreducible ideal in $R$ also irreducible in $R[x]$? Thank you! I've taken the liberty to edit your proof a little. As you say, it's not short, but quite elementary. Nice. Aug 31 suggested approved edit on Is an irreducible ideal in $R$ also irreducible in $R[x]$? Aug 31 comment Lattice Flatness Measure Can you give some more examples: How should that flatness measure be different from just height? Aug 31 awarded Quorum Aug 31 awarded Nice Question Aug 31 comment Is an irreducible ideal in $R$ also irreducible in $R[x]$? Thank you for your answer. There are a number of things that I don't understand yet. Can you please explain: Why can you saturate at X ("since X is indeterminate")? In Claim 1, are you saying that you want to choose f,g so that Claim 1 is satisfied? What do you mean by "then we replace"/why can you replace $f$? And then David Lamperts comment. It would be great if you could fill in some more detail. Thanks! Aug 27 asked Is an irreducible ideal in $R$ also irreducible in $R[x]$? Aug 5 awarded Tumbleweed Jul 31 revised almost diagonal Positive semidefinite Matrix Lambda (M) and other minor things. Jul 31 suggested approved edit on almost diagonal Positive semidefinite Matrix Jul 31 answered When is a power of an indeterminate in an ideal with 2 generators? Jul 29 revised The spring Markov chain on $\mathbb{N}$ Close votes are coming in without comments -> formulate a concrete question in the end.