PostDoc position in the research group of Algebra and Discrete Mathematics. Strong background in one or more of the areas discrete and combinatorial geometry, combinatorial commutative algebra, topological, geometric or algebraic combinatorics and discrete mathematics.

PostDoc Stelle in der AG Geometrie verfügbar - Sie haben Freude an der Bearbeitung aktueller Forschungsprojekte und bringen sich gerne engagiert in der Lehre ein? Bewerben Sie sich mit einem Forschungsprofil in einem der folgenden Fachgebiete: metrische Geometrie, geometrische Gruppentheorie, algebraische Kombinatorik oder geometrische/kombinatorische Darstellungstheorie

The Institute of Algebra, Number Theory and Discrete Mathematics invites applications for the position of a Research Assistant (Postdoc, m/f/d) in Algebra and/or Combinatorics (Salary Scale 13 TV-L, 100 %).

The Max Planck Institute for Mathematics in the Sciences (MPI MiS) is a research center for pure and applied mathematical research located in Leipzig, Germany. The institute is committed to innovative fundamental research, and to transferring concepts and structures from mathematics into other academic fields. The broader scientific environment in Leipzig includes two other Max Planck Institutes (Cognitive Science and Evolutionary Anthropology) as well as the University of Leipzig. For our upcoming research group "Interdisciplinary Frontiers of Algebraic Geometry" led by İrem Portakal, we offer a 3-year PhD position. The expected starting date of the position is January 1st, 2024. We seek outstanding students who enjoy working in a collaborative environment. Applicants should have a degree in mathematics or related fields with an interest in algebra, geometry and computation.

Applicants should hold, or be about to complete, a doctorate in a relevant mathematical subject area such as algebra or combinatorics. Research experience in asymptotic group theory will be an advantage, but is not essential. The appointee will be required to contribute to the Faculty of Mathematics' teaching portolio (4 hours per week). German language skills are not a necessary requirement, but the ability and willingness to learn German to be able to teach in German after a year is. Support for language tuition is available.

We seek open-minded scholars with an exceptional research record. Strong computational skills are desirable. For our new ERC-Synergy project Universe+, we are especially interested in candidates who are excited about connections with physics.

The Faculty of Mathematics at Bielefeld University (joint with MPI MiS Leipzig) invites applications for one PhD position for the project "Convexity and Grassmannians in Statistical Inference" which is a project at the interface of Statistics and Combinatorics. The position will be based at Bielefeld University, but the doctoral researcher will also work for two semesters in the Nonlinear Algebra group at MPI MiS in Leipzig. Applicants should have expertise in one of the following areas and high motivation to learn more about the other area:

• statistics, in particular high-dimensional statistics, algebraic statistics, matrix and tensor methods, and manifold learning

• combinatorics, in particular convex bodies, Grassmannians, matroids, and connections to algebraic geometry

The Faculty of Mathematics at the Ruhr-Universität Bochum invites applications for the position of a Junior Professor (without tenure track) (m/f/d) for Combinatorics (Salary Scale W 1) to start on as soon as possible. The successful candidate will represent the subject of Combinatorics in research and teaching. Applicants should have demonstrated excellence in an active area of Combinatorics. Preference will be given to applicants working at interconnections of the following fields: enumerative combinatorics, reflections and symmetries, commutative algebra, discrete geometry, matroid theory, convexity and lattices, applications such as the theory of amplituhedra and positive geometry. We are looking for a junior scientist with an internationally visible research profile who complements the existing research expertise and fundings at the Faculty of Mathematics. A close collaboration with the priority program SPP2458 "Combinatorial Synergies" will be expected. The teaching duties will include mathematics courses at undergraduate and graduate level. The teaching load is reduced.

The department of mathematics at OvGU Magdeburg seeks to fill a W2 professorship in Geometry, in particular algebraic geometry, non-linear algebra, tropical geometry, and discrete geometry.

We are advertising a PhD position (75% E13) in the joint project "K-Theory and Normal Complexes" of FU Berlin and EPF Lausanne within the framework of the DFG Priority Programme SPP 2458 "Combinatorial Synergies".

This is a project at the interface of Algebraic Geometry and Combinatorics. The position will be based in Berlin in the group of Christian Haase, but the doctoral researcher will be co-advised by Leonid Monin in Lausanne.

No teaching obligation, Master's degree or equivalent required. Deadline is May 20, 2024.

We are advertising three PhD positions (75% E13) in the project "Simpliciality in Arrangements and Matroids", a cooperation between the Universities of Bielefeld, Frankfurt, and Hannover within the DFG priority program "Combinatorial Synergies" (SPP 2458). One doctoral position is advertised at each of the three locations. The successful candidates will work on broad research topics in the areas of algebraic and geometric combinatorics, discrete geometry, and algebra in close cooperation with the other projects members. The positions come without teaching duties.

More information about the project can be found here. If you have further questions, feel free to get in touch with any of the PIs.

See the official listings (Bielefeld, Frankfurt, Hannover) for the application process. Please send only one application. Application deadline is June 10, 2024.

The Institute of Mathematics at Goethe University Frankfurt is advertising a position as a

Postdoctoral Researcher (E 13 TV-G-U)

in the group of Martin Ulirsch for the duration of 2 years. The salary is based on the rules of TV-G-U. The earliest possible starting date is 1. July 2024.

The appointment is funded by the project of the German Research Foundation (DFG) with the title “Rethinking Tropical Linear Algebra: Bimatroids, Buildings, and Applications”, which is part of the newly establish DFG priority program SPP 2458 "Combinatorial Synergies".

The successful candidate must have completed a Ph.D. at the time of employment. Candidates with prior knowledge in tropical geometry, the theory of matroids, the geometry of buildings, or, more generally, in combinatorial algebraic geometry are particularly encouraged to apply.

Applications with the usual documents (letter including your preferred starting date, CV, research statement, addresses of two referees willing to provide recommendation letters upon request) should be sent by 11. June 2024 to

ulirsch@math.uni-frankfurt.de

We are advertising a new PhD position (75% E13) in the "Algebraic and Geometric Methods in Data Analysis" group at the Institute of Mathematics of TU Berlin. The position is part of the Combinatorial Synergies (SPP 2458) project "Combinatorial Methods for Learning Max-Linear Bayesian Networks" which is a cooperation between TU Berlin and TU Munich. This research project involves synergies between combinatorics, in particular graph theory and tropical geometry, and statistics. It is focused on developing new combinatorial algorithms which can be used to reconstruct graphs which represent causal relationships between extreme events. The deadline is June 14, 2024. Please send your application with the reference number and the usual documents (all combined in a single pdf file, max 5 MB) by email to Beate Nießen (niessen@math.tu-berlin.de).

The Applied Algebra Group at TU Braunschweig is opening PhD student for my group in the area of nonnegativity and polynomial optimization as part of the project "Sums of Nonnegative Circuit Polynomials and Combinatorics in Polynomial Optimization" Our group pursues the project in cooperation with the group of Thorsten Theobald at Goethe University, Frankfurt am Main, Germany.

Further Information about the project is provided here and here.

Deadline for applications is June 14th. The earliest starting date is August 1st, but it is negotiable. Please reach out to Timo de Wolff in case that you need further information.

The Combinatorics Group at Ruhr-University Bochum invites applications for 1-2 PhD positions in enumerative and algebraic combinatorics, with a particular emphasis on introducing machine learning techniques within this area. Please check the job announcement and a brief summary of the project.

If you are interested in pursuing a PhD in this area, with a very strong background in research areas related to our research group and/or in machine learning, please get in contact with us. The positions come without teaching load and the starting date is negotiable.

In their recent paper, Cuntz and Kühne introduced a special class of hyperplane arrangements stemming from a given (connected) graph G, so called connected subgraph arrangements A(G). They include such prominent classes such as the braid arrangements, Shi arrangements, and resonance arrangements among countless many others. The aims of this project are fourfold. Firstly, we intend to answer some of the questions raised in the work of Cuntz and Kühne. Secondly we aim to strengthen several of the results from their paper. Thirdly we hope to prove some new results for this class of arrangements, e.g. over finite fields. In their work, Cuntz and Kühne classified all connected subgraph arrangements over the rationals which are free, factored, simplicial or supersolvable. In this project we aim to extend and strengthen these results as follows. We aim to show that a connected subgraph arrangement A(G) over the rationals is free if and only if it is inductively free; that it is factored if and only if it is inductively factored. Cuntz and Kühne specifically raise the question of classifying members among the arrangements A(G) over the rationals that are aspherical. This is probably a hopeless task, as determining asphericity for a given set of ar- rangements is a notoriously difficult undertaking. However, our further aim is to compile a comprehensive list of graphs G for which A(G) is not aspherical. As asphericity is a local property, this then allows us to conclude that large classes of connected subgraph arrangements are not aspherical. These in particular encompass the aforementioned resonance arrangements of rank at least 5.

The classes of free arrangements and free multiarrangments play pivotal roles in the theories of hyperplane arrangements and multiarrangements, respectively. Ziegler showed in his seminal work that a free arrangement A gives rise to a canonical free multiarrangement on any restiction of A with exponents only depending on the exponents of A. We refer to this construction as a Ziegler restriction. In 2010, Yoshinaga asked for a reverse procedure, which he coins as extension: given a free multiarrangement is this the Ziegler restriction of a free arrangement A? In general this is not the case. We call this a Ziegler extension. The ultimate goal of Yoshinaga's work in this context is a complete description of all free intermediate arrangements between the extended Shi and extended Catalan arrangements for simply laced underlying root systems. There is a long history and continued interest in the literature regarding questions of freeness of the families of extended Shi and extended Catalan arrangements. Among other aspects, this proposal is a contribution to this theory. The goal of this project is to continue Yoshinaga's investigation about extensions of free multiarrangements.

Firstly, we aim to answer some of the questions and conjectures raised in Yoshinaga's paper. Secondly, we intend to extend the classification from this work to all intermediate free arrangements between extended Shi and extended Catalan arrangements for arbitrary Coxeter types, i.e. to also include non-simply laced ones. Thirdly, we plan to investigate extensions of free multiarrangements over finite fields, a topic which has not been studied in the literature as of yet. Finally, in a fourth research stand we aim at studying free extensions of various natural free complex multireflection arrangements which were defined and studied in earlier work of the PI and his coauthors. These extensions then might be thought of as complex (non-real) analogues of extended Shi and extended Catalan arrangements.

The project aims at a deeper understanding of several recently discovered mechanisms from the theory of Lorentzian polynomials that preserve log-concavity. Beyond the intrinsic interest, our main motivation for this investigation is to obtain precise information about the equality cases in log-concave inequalities. The project will explore connections and synergies between combinatorics, convexity, and algebraic geometry.

At the University of Greifswald’s Institute of Mathematics and Computer Science, Junior Professorship Stochastic Analysis, in the Faculty of Mathematics and Natural Sciences, there is a job vacancy that is, subject to budgetary regulations, available at the earliest possible date, for a part-time (75 %) Research Assistant.

The fixed-term contract is for a period of 3 years. Payment will be made according to pay group 13 TV-L Wissenschaft.

The position is part of the project "Counting Permutation and Chirotope Patterns: Algorithms, Algebra, and Applications", which is part of the DFG Priority Programme SPP 2458 "Combinatorial Synergies".

Job Description:

• research on the combinatorial, algebraic and algorithmic structure of permutation and chirotope patterns

Job Requirements:

• a degree (master’s, or equivalent) in mathematics, computer science, or physics
• fluency in the English language
• prior experience with algebraic combinatorics, algorithmic combinatorics, (higher) category theory or statistics is beneficial

This vacancy is open to all persons, irrespective of gender. Severely disabled applicants with the same qualifications will be considered with preference.

Goethe University Frankfurt am Main invites applications for the position of Professor (W2) of Computer-Oriented Discrete Mathematics in the Institute of Mathematics at the Faculty of Computer Science and Mathematics. This civil servant or public employee position will start as soon as possible.

We are seeking a candidate whose interests complement the existing capabilities of the Institute of Mathematics in the focus unit Discrete Mathematics and who offers possibilities for cooperation in this surround. The professional profile should be documented by relevant highly ranked mathematical publications.

Current application perspectives, e.g. in one of the areas Optimization or Machine learning, are welcome. Experience in acquiring third-party funding are expected, as is the willingness to cooperate with existing working groups in mathematics and computer science, with the research profile areas of Goethe University and the interdisciplinary Center for Critical Computational Studies (C3S) as well as within the strategic alliance of the Rhine-Main-Universities (RMU). Furthermore, the successful applicant will participate in the teaching tasks of the department, which include, in particular, courses for first and second year students in mathematics and computer science.

The formal hiring requirements are defined in sections 67, and 68 of the Hessian Higher Education Act (Hessisches Hochschulgesetz). Goethe University is an equal opportunity employer, committed to diversity and inclusion. In particular, we are welcoming applications by qualified women and people with a migrant background. At Goethe University, a special emphasis is placed on creating and sustaining a family-friendly work and research environment. Where applicants are otherwise equally qualified, preference is given to candidates with disabilities or equivalent. The same applies to women in fields in which they are under-represented.

To apply, please send a CV, a list of publications, an overview of your research and teaching activities as well as transcripts and a selection of recent course evaluations as a single PDF document by 09 July 2024 to the Dean of the Department of Computer Science and Mathematics, e-mail: application@fb12.uni-frankfurt.de. If you have any questions, please contact Prof. Dr. Thorsten Theobald at theobald@math.uni-frankfurt.de. Further information about the appointment process, the legal framework and data protection: www.professorship-vacancies.uni-frankfurt.de

The Faculty of Mathematics at Bielefeld University is looking to appoint a researcher ("wissenschaftlicher Mitarbeiterin" (m/f/d)) to work with Christopher Voll within the remit of the TRR 358 Integral Structures in Geometry and Representation Theory on a project on Zeta functions of integral quiver representations.

The appointment will be made for two years.

For details about C. Voll's research interests, see

https://www.uni-bielefeld.de/fakultaeten/mathematik/ag/voll/research/

The starting date is negotiable, but preferably 01 January 2025. A part-time appointment may be negotiated. The relevant pay scale is E 13 TV-L.

Applicants should hold, or be about to complete, a doctorate in a relevant mathematical subject area such as algebra or combinatorics. Research experience in asymptotic group theory will be an advantage, but is not essential.

The appointee will be invited to contribute to the Faculty of Mathematics' teaching portolio (at most 4 hours per week).

German language skills are not a necessary requirement, but the ability and willingness to learn German to be able to teach in German after a year is. Support for language tuition is available.

Applications should comprise, in a single pdf-file, the following:

• a detailed Curriculum Vitae,

• a concise research plan,

• addresses of up to three academics who may be contacted for academic references,

• relevant papers and theses, as relevant.

Applications should be made via this form.

The closing date for applications is 16 July 2024. Interested candidates may contact Christopher Voll to discuss further details.