Matches in SemOpenAlex for { <https://semopenalex.org/work/W2893530259> ?p ?o ?g. }
- W2893530259 abstract "In [2], the authors prove Stillman's conjecture in all characteristics and all degrees by showing that, independent of the algebraically closed field $K$ or the number of variables, $n$ forms of degree at most $d$ in a polynomial ring $R$ over $K$ are contained in a polynomial subalgebra of $R$ generated by a regular sequence consisting of at most ${}^eta!B(n,d)$ forms of degree at most $d$: we refer to these informally as small subalgebras. Moreover, these forms can be chosen so that the ideal generated by any subset defines a ring satisfying the Serre condition R$_eta$. A critical element in the proof is to show that there are functions ${}^eta!A(n,d)$ with the following property: in a graded $n$-dimensional $K$-vector subspace $V$ of $R$ spanned by forms of degree at most $d$, if no nonzero form in $V$ is in an ideal generated by ${}^eta!A(n,d)$ forms of strictly lower degree (we call this a {it strength} condition), then any homogeneous basis for $V$ is an R$_eta$ sequence. The methods of cite{AH2} are not constructive. In this paper, we use related but different ideas that emphasize the notion of a {it key function} to obtain the functions ${}^eta!A(n,d)$ in degrees 2, 3, and 4 (in degree 4 we must restrict to characteristic not 2, 3). We give bounds in closed form for the key functions and the ${}^eta!A$ functions, and explicit recursions that determine the functions ${}^eta!B$ from the ${}^eta!A$ functions. In degree 2, we obtain an explicit value for ${}^eta!B(n,2)$ that gives the best known bound in Stillman's conjecture for quadrics when there is no restriction on $n$. In particular, for an ideal $I$ generated by $n$ quadrics, the projective dimension $R/I$ is at most $2^{n+1}(n - 2) + 4$." @default.
- W2893530259 created "2018-10-05" @default.
- W2893530259 creator A5033588315 @default.
- W2893530259 creator A5056285909 @default.
- W2893530259 date "2018-09-30" @default.
- W2893530259 modified "2023-09-27" @default.
- W2893530259 title "Strength conditions, small subalgebras, and Stillman bounds in degree $leq 4$" @default.
- W2893530259 cites W1519801683 @default.
- W2893530259 cites W15792735 @default.
- W2893530259 cites W1969062391 @default.
- W2893530259 cites W1999171802 @default.
- W2893530259 cites W2006766469 @default.
- W2893530259 cites W2028213871 @default.
- W2893530259 cites W2029366421 @default.
- W2893530259 cites W2054356605 @default.
- W2893530259 cites W2065549534 @default.
- W2893530259 cites W2077136168 @default.
- W2893530259 cites W2095378078 @default.
- W2893530259 cites W2133331905 @default.
- W2893530259 cites W2137326657 @default.
- W2893530259 cites W2170699085 @default.
- W2893530259 cites W2170793153 @default.
- W2893530259 cites W2184808114 @default.
- W2893530259 cites W2313163255 @default.
- W2893530259 cites W2808576644 @default.
- W2893530259 cites W2963502226 @default.
- W2893530259 cites W2964016782 @default.
- W2893530259 cites W2965853388 @default.
- W2893530259 cites W2164154628 @default.
- W2893530259 hasPublicationYear "2018" @default.
- W2893530259 type Work @default.
- W2893530259 sameAs 2893530259 @default.
- W2893530259 citedByCount "4" @default.
- W2893530259 countsByYear W28935302592019 @default.
- W2893530259 countsByYear W28935302592020 @default.
- W2893530259 countsByYear W28935302592021 @default.
- W2893530259 crossrefType "posted-content" @default.
- W2893530259 hasAuthorship W2893530259A5033588315 @default.
- W2893530259 hasAuthorship W2893530259A5056285909 @default.
- W2893530259 hasConcept C101044782 @default.
- W2893530259 hasConcept C111472728 @default.
- W2893530259 hasConcept C114614502 @default.
- W2893530259 hasConcept C118615104 @default.
- W2893530259 hasConcept C121332964 @default.
- W2893530259 hasConcept C134306372 @default.
- W2893530259 hasConcept C136119220 @default.
- W2893530259 hasConcept C138885662 @default.
- W2893530259 hasConcept C14036430 @default.
- W2893530259 hasConcept C17103678 @default.
- W2893530259 hasConcept C17744445 @default.
- W2893530259 hasConcept C178790620 @default.
- W2893530259 hasConcept C185592680 @default.
- W2893530259 hasConcept C199539241 @default.
- W2893530259 hasConcept C200288055 @default.
- W2893530259 hasConcept C202444582 @default.
- W2893530259 hasConcept C203701370 @default.
- W2893530259 hasConcept C24890656 @default.
- W2893530259 hasConcept C2775997480 @default.
- W2893530259 hasConcept C2776639384 @default.
- W2893530259 hasConcept C2778112365 @default.
- W2893530259 hasConcept C2780378348 @default.
- W2893530259 hasConcept C2780990831 @default.
- W2893530259 hasConcept C32834561 @default.
- W2893530259 hasConcept C33923547 @default.
- W2893530259 hasConcept C54355233 @default.
- W2893530259 hasConcept C67996461 @default.
- W2893530259 hasConcept C78458016 @default.
- W2893530259 hasConcept C86803240 @default.
- W2893530259 hasConcept C90119067 @default.
- W2893530259 hasConcept C9485509 @default.
- W2893530259 hasConceptScore W2893530259C101044782 @default.
- W2893530259 hasConceptScore W2893530259C111472728 @default.
- W2893530259 hasConceptScore W2893530259C114614502 @default.
- W2893530259 hasConceptScore W2893530259C118615104 @default.
- W2893530259 hasConceptScore W2893530259C121332964 @default.
- W2893530259 hasConceptScore W2893530259C134306372 @default.
- W2893530259 hasConceptScore W2893530259C136119220 @default.
- W2893530259 hasConceptScore W2893530259C138885662 @default.
- W2893530259 hasConceptScore W2893530259C14036430 @default.
- W2893530259 hasConceptScore W2893530259C17103678 @default.
- W2893530259 hasConceptScore W2893530259C17744445 @default.
- W2893530259 hasConceptScore W2893530259C178790620 @default.
- W2893530259 hasConceptScore W2893530259C185592680 @default.
- W2893530259 hasConceptScore W2893530259C199539241 @default.
- W2893530259 hasConceptScore W2893530259C200288055 @default.
- W2893530259 hasConceptScore W2893530259C202444582 @default.
- W2893530259 hasConceptScore W2893530259C203701370 @default.
- W2893530259 hasConceptScore W2893530259C24890656 @default.
- W2893530259 hasConceptScore W2893530259C2775997480 @default.
- W2893530259 hasConceptScore W2893530259C2776639384 @default.
- W2893530259 hasConceptScore W2893530259C2778112365 @default.
- W2893530259 hasConceptScore W2893530259C2780378348 @default.
- W2893530259 hasConceptScore W2893530259C2780990831 @default.
- W2893530259 hasConceptScore W2893530259C32834561 @default.
- W2893530259 hasConceptScore W2893530259C33923547 @default.
- W2893530259 hasConceptScore W2893530259C54355233 @default.
- W2893530259 hasConceptScore W2893530259C67996461 @default.
- W2893530259 hasConceptScore W2893530259C78458016 @default.
- W2893530259 hasConceptScore W2893530259C86803240 @default.
- W2893530259 hasConceptScore W2893530259C90119067 @default.