Year: 2024

A Countable Prime Avoidance Theorem and Its Generalization to Prime Submodules

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M. R. Pournaki, Sharif University of Technology. Date: 29th of March, 2024, Friday, Time: 13.00 – 14.00. Place: Dokuz Eylül Univ., Tınaztepe Campus, Faculty of Science, Department of Mathematics, Classroom B255.

Abstract: One of the fundamental cornerstones of commutative ring theory is the prime avoidance theorem, which states that, if \frak{p_1},\ldots,\frak{p_n} are prime ideals of R and \frak{a} is an ideal of R such that \frak{a}\subseteq {\bigcup_{i=1}^n} \frak{p_i}, then \frak{a}\subseteq \frak{p_i} for some 1\leq i\leq n. In this talk, we give a proof for the countable version of this theorem due to Sharp and Vamos. The proof uses the celebrated Baire’s category theorem in metric spaces. We then discuss its generalization to the prime submodules.

A Glimpse to the Stanley Depth: A Geometric Invariant for Modules

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M. R. Pournaki, Sharif University of Technology. Date: 22nd of March, 2024, Friday, Time: 13.00 – 14.00. Place: Dokuz Eylül Univ., Tınaztepe Campus, Faculty of Science, Department of Mathematics, Classroom B255.

Abstract: Stanley depth is a geometric invariant of a module which has some common properties with the homological depth invariant. In this talk, we first review briefly the basic concepts of Stanley depth and then discuss some of the recent developments in the theory.

 

 

 

A Glimpse to Unit Graphs: The Graphs Arising From Rings

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M. R. Pournaki, Sharif University of Technology. Date: 15th of March, 2024, Friday, Time: 13.00 – 14.00. Place: Dokuz Eylül Univ., Tınaztepe Campus, Faculty of Science, Department of Mathematics, Classroom B255.

Abstract: The ring \mathbb{Z}_2\times\mathbb{Z}_2, having only one unit, cannot be generated by its units. It turns out, in the general theory of rings, that this is essentially the only example. In this talk, we give an elementary proof of “A finite commutative ring with nonzero identity is generated by its units if and only if it cannot have \mathbb{Z}_2\times\mathbb{Z}_2 as a quotient.” The proof uses graph theory and pointed out to the story of how unit graphs have been arisen. At the end, we discuss some of the recent developments in the theory.

When Three Subjects of Mathematics Meet Each Other

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M. R. Pournaki, Sharif University of Technology. Date: 8th of March, 2024, Friday, Time: 13.00 – 14.00. Place: Dokuz Eylül Univ., Tınaztepe Campus, Faculty of Science, Department of Mathematics, Class B255.

Abstract: Fermat’s little theorem states that if p is a prime number, then a^p \equiv a (mod p) holds true for any integer a. One may ask what happens when p is not a prime. The answer to this question seems little known to mathematicians, even to number theorists (as Dickson said in his “History of the Theory of Numbers”). In this talk, we discuss the missing result which is essentially due to Gauss and its generalizations.

Quantitative unique continuation or “If we don’t know everything, how much do we actually know”?

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Matthias Täufer, Analysis group, FernUniversität in Hagen, Germany Date: 1th March 2024, Friday Time: 13:00 Place: DEU, Faculty of Science, Department of Mathematics, Room B255

Abstract: Unique continuation is a basic property of many partial differential equations stating that solutions vanishing on subsets must be identically zero. In many cases one would like to have a quantitative version of that, meaning that one can bound the norm of solutions by their norm on subsets. In this talk, we review some history of quantitative unique continuation and present several results on quantitative unique continuation in unbounded domains. Based on joint works with Ivica Nakic (Zagreb), Martin Tautenhahn (Leipzig), Sedef Özcan (Dokuz Eylül), Paul Pfeiffer (Hagen), Albrecht Seelmann (Dortmund) and Ivan Veselic (Dortmund).

How I Succeeded? From Student to Academician

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This month’s theme of our career event, which we organized in cooperation with DEU Career Planning Center and DEU Faculty of Science Department of Mathematics, is “How I Succeeded”. The talk titled “From Student to Academician”, which we will hold under the moderation of our Mathematics Department KPMI Student Representative Ayşenur YAZICI and with the participation of Mathematics Department faculty member Asst.Prof. Dr. Murat ALTUNBULAK, is open to everyone and everyone who is interested is welcome.

Speaker: Asst.Prof.Dr. Murat ALTUNBULAK
Moderator: Ayşenur YAZICI
Date and Time: 23.02.2023, 12:00
Location: Classroom B256 (Faculty of Science, Department of Mathematics)

Computing eigenvalues of the discrete p-Laplacian via graph surgery

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Matthias Hofmann, Texas A&M University Date: 16th February 2024, Friday Time: 13:00 Place: DEU, Faculty of Science, Department of Mathematics, Room B255

Abstract: We discuss the dependence of the eigenvalues and eigenfunctions for the discrete signed p-Laplacian under perturbation by a cut parameter. In particular, we prove a formula for the derivative of the eigenvalues and show that the eigenvalues of the discrete signed p-Laplacian on the original graph can be characterized via extremal points of the perturbed system. In this context, we elaborate on how graph surgery can be used in order to compute eigenvalues of the discrete (signed) p-Laplacian by looking at some examples. The derivation formula is reminiscent of the formula for linear eigenvalue problems given by the Hellmann-Feynman theorem and our results extend previous results for the linear case p=2 attained by [Berkolaiko, Anal. PDE 6 (2013), no. 5, 12131233].

AES Encryption Surrounds Us; We Surround AES Encryption

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Orhun Kara, İzmir Institute of Technology . Date: 31th of January, 2024, Wednesday, Time: 10.30 – 12.00. Place: Dokuz Eylül Univ., Tınaztepe Campus, Faculty of Science, Department of Mathematics, Room B206 (Online-Sakai-Graduate Meetings).

Abstract:

The NIST Advanced Encryption Standard, AES, is without doubt the most used encryption algorithm all over the world. AES supplies confidentiality in almost all the ubiquitous cryptographic protocols including Whatsapp security, TLS, WPA. In this talk, we introduce algebraic aspects and the design philosophy of AES. Moreover, we try to convince the audience that AES appears sufficiently secure to protect our data by presenting supporting security evidence and introducing some unsuccessful attack attempts.