Members: Prof. Dr. Holger Brenner,  Prof. Dr. Winfried Bruns,  Prof. Dr. Tim Römer 

Former Members: Dr. Peter Schenzel (Martin-Luther-Universität Halle-Wittenberg), Dr. Bogdan Ichim

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Projects:

Affine semigroups, toric rings and varieties

We are interested in:

• Ring theoretic properties of affine semigroup rings (normality, Koszul property, numerical invariants).
• Structure of affine semigroups, in particular normality and covering properties.
• Divisorial linear algebra.
• Polyhedral K-theory, which is derived from the automorphismgroups of polytopal semigroup rings.

Cooperation with:

• M. Brun, University of Bergen (Norway)
• J. Gubeladze, San Francisco State University (USA)
• J. Herzog, University of Duisburg-Essen (Germany)
• N. V. Trung, Institute of Mathematics Hanoi (Vietnam)

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Determinantal and related rings

We are interested in:

• Structure of determinantal rings of Rees- and associated graded rings of determinantal ideals by initial methods.
• F-rationality, canonical modules, divisor class groups

Cooperation with:

• A. Conca, University of Genua (Italy)
• J. Herzog, University of Duisburg-Essen (Germany)

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Homological commutative algebra

We are interested in:

• Cohen-Macaulay rings and canonical module
• Extended degree functions
• Structure of free resolutions
• The multiplicity conjecture

Cooperation with:

• M. Brun, University of Bergen (Norway)
• J. Herzog, University of Duisburg-Essen (Germany)
• J. C. Migliore, University of Notre Dame (USA)
• U. Nagel, University of Kentucky (USA)
• W. V. Vasconcelos, Rutgers University (USA)
• U. Vetter, University of Oldenburg (Germany)