Dr Moty Katzman
School of Mathematics and Statistics
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Director of Computing
+44 114 222 3710
Full contact details
School of Mathematics and Statistics
J16
Hicks Building
Hounsfield Road
Sheffield
S3 7RH
 Research interests

Dr Katzman's research is in the area of commutative algebra. Specifically, he is interested in the following.
Characteristic p methods
Certain theorems in algebra can be proved by showing that they hold in positive characteristic, and in characteristic p one has extra structure given by the Frobenius map x↦xp. There are several tools, notably tight closure, which exploit this extra structure to prove some remarkable theorems.
Local cohomology modules
This modules derive their importance partly from the fact that they detect interesting properties of modules over commutative rings (e.g., depth.) Unfortunately, these objects tend to be very big are rather mysterious. It is very difficult to describe them in any detail even in seemingly easy cases. Dr. Katzman has recently been producing both examples showing that these objects are more complicated than previously conjectured but also instances where they can be understood fairly well.
Combinatorial aspects
One of the simplest family of modules imaginable are monomial ideals in polynomial rings and, perhaps surprisingly, these objects have a very rich structure, in some sense richer than the structure of graphs. Dr Katzman has recently been studying certain monomial ideals associated with graphs a discovering some surprising connections between the algebraic and combinatorial properties of these objects.
 Publications

Show: Featured publications All publications
Featured publications
Journal articles
 The support of local cohomology modules. International Mathematics Research Notices, 2018(23), 71377155. View this article in WRRO
 Dmodule and Fmodule length of local cohomology modules. Transactions of the American Mathematical Society, 370, 85518580. View this article in WRRO
 Global parameter test ideals. Journal of Algebra. View this article in WRRO
 An extension of a theorem of Hartshorne. Proceedings of the American Mathematical Society, 144(3), 955962. View this article in WRRO
 Rings of Frobenius operators. Mathematical Proceedings of the Cambridge Philosophical Society, 157(1), 151167. View this article in WRRO
All publications
Journal articles
 View this article in WRRO Lyubeznik numbers, $F$modules and modules of generalized fractions.
 A datadriven approach for predicting printability in metal additive manufacturing processes. Journal of Intelligent Manufacturing. View this article in WRRO
 The TestIdeals package for Macaulay2. Journal of Software for Algebra and Geometry, 9(2), 89110. View this article in WRRO
 FFRT properties of hypersurfaces and their Fsignatures. Journal of Algebra and its Applications. View this article in WRRO
 Strong Fregularity and generating morphisms of local cohomology modules. Journal of Algebra, 525, 1941. View this article in WRRO
 Multiplicity bounds in prime characteristic. Communications in Algebra, 47(6), 24502456. View this article in WRRO
 The support of local cohomology modules. International Mathematics Research Notices, 2018(23), 71377155. View this article in WRRO
 Dmodule and Fmodule length of local cohomology modules. Transactions of the American Mathematical Society, 370, 85518580. View this article in WRRO
 Global parameter test ideals. Journal of Algebra. View this article in WRRO
 An extension of a theorem of Hartshorne. Proceedings of the American Mathematical Society, 144(3), 955962. View this article in WRRO
 An algorithm for producing Fpure ideals. Archiv der Mathematik, 103(5), 421433. View this article in WRRO
 Rings of Frobenius operators. Mathematical Proceedings of the Cambridge Philosophical Society, 157(1), 151167. View this article in WRRO
 CastelnuovoMumford regularity and the discreteness of Fjumping coefficients in graded rings. Transactions of the American Mathematical Society, 7(366), 35193533.
 Annihilators of Artinian modules compatible with a Frobenius map. Journal of Symbolic Computation, 60, 2946. View this article in WRRO
 Two interesting examples of Dmodules in characteristic p>0. Bulletin of the London Mathematical Society, 44(6), 11161122.
 An algorithm for computing compatibly Frobenius split subvarieties. Journal of Symbolic Computation, 47(8), 9961008.
 An upper bound on the number of Fjumping coefficients of a principal ideal. Proceedings of the American Mathematical Society, 139(12), 41934197.
 A NONFINITELY GENERATED ALGEBRA OF FROBENIUS MAPS. P AM MATH SOC, 138(7), 23812383.
 Frobenius maps on injective hulls and their applications to tight closure. J LOND MATH SOC, 81, 589607.
 On the discreteness and rationality of Fjumping coefficients. J ALGEBRA, 322(9), 32383247. View this article in WRRO
 Parametertestideals of CohenMacaulay rings. COMPOS MATH, 144(4), 933948.
 On ideals of minors of matrices with indeterminate entries. COMMUN ALGEBRA, 36(1), 104111. View this article in WRRO
 Frobenius test exponents for parameter ideals in generalized CohenMacaulay local rings. J ALGEBRA, 305(1), 516539. View this article in WRRO
 Characteristicindependence of Betti numbers of graph ideals. J COMB THEORY A, 113(3), 435454. View this article in WRRO
 View this article in WRRO On the arithmetic of tight closure. J AM MATH SOC, 19(3), 659672.
 Uniform behaviour of the Frobenius closures of ideals generated by regular sequences. J ALGEBRA, 295(1), 231246. View this article in WRRO
 Counting monomials. J ALGEBR COMB, 22(3), 331341. View this article in WRRO
 The Hilbert series of algebras of the Veronese type. COMMUN ALGEBRA, 33(4), 11411146. View this article in WRRO
 View this article in WRRO Some properties of top graded local cohomology modules. J ALGEBRA, 259(2), 599612.
 View this article in WRRO An example of an infinite set of associated primes of a local cohomology module. J ALGEBRA, 252(1), 161166.
 View this article in WRRO Associated primes of graded components of local cohomology modules. T AM MATH SOC, 354(11), 42614283.
 Weak FRegularity Deforms in QGorenstein Rings. Journal of Algebra, 204(1), 281285.
 The Complexity of Frobenius Powers of Ideals. Journal of Algebra, 203(1), 211225.
 The Cohomological Dimension of a Resultant Variety in Prime Characteristicp. Journal of Algebra, 191(2), 510517.
 Finite criteria for weak $mathrm{F}$regularity. Illinois Journal of Mathematics, 40(3), 453463.
 Some properties and applications of $F$finite $F$modules.
 View this article in WRRO Finiteness of $bold{bigcup_e Ass F^e(M)}$ and its connections to tight closure. Illinois Journal of Mathematics 40 (1996) pp. 330337.
 View this article in WRRO Bipartite graphs whose edge algebras are complete intersections. Journal of Algebra, 220 (1999) pp. 519530.
Conference proceedings papers
 The support of top graded local cohomology modules. Commutative Algebra: Geometric, Homological, Combinatorial and Computational Aspects, Vol. 244 (pp 165174)
Preprints
 Lyubeznik numbers, $F$modules and modules of generalized fractions, arXiv.
 The TestIdeals package for Macaulay2, arXiv.
 Strong $F$regularity and generating morphisms of local cohomology modules, arXiv.
 FFRT Properties of hypersurfaces and their Fsignature, arXiv.
 Global parameter test ideals, arXiv.
 An extension of a theorem of Hartshorne, arXiv.
 An algorithm for producing Fpure ideals, arXiv.
 Rings of Frobenius operators, arXiv.
 An algorithm for computing compatibly Frobenius split subvarieties, arXiv.
 Two interesting examples of $mathcal{D}$modules in characteristic $p>0$, arXiv.
 An upper bound on the number of Fjumping coefficients of a principal ideal, arXiv.
 Research group
 Grants

Past grants, as Principal Investigator
Common threads in the theories of Local Cohomology, Dmodules and Tight Closure and their interactions EPSRC Prime characteristic methods in commutative algebra EPSRC Graded components of local cohomology modules EPSRC Past grants, as Coinvestigator
Tailorable Adaptive Connected Digital Additive Manufacturing (TACDAM)
 Teaching activities

MAS346 Groups and Symmetry MAS348 Game Theory