From itabrunke@zedat.fu-berlin.de Mon Jul 04 18:49:06 2022 Received: from outpost1.zedat.fu-berlin.de ([130.133.4.66]) by list1.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1o8PFt-001dOr-BT; Mon, 04 Jul 2022 18:49:01 +0200 Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1o8PFt-000HyM-8p; Mon, 04 Jul 2022 18:49:01 +0200 Received: from ip5f5af788.dynamic.kabel-deutschland.de ([95.90.247.136] helo=[192.168.0.2]) by inpost2.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtpsa (TLS1.3) tls TLS_AES_128_GCM_SHA256 (envelope-from ) id 1o8PFs-000sQ7-Ve; Mon, 04 Jul 2022 18:49:01 +0200 From: Ita Brunke To: facets-of-complexity@lists.fu-berlin.de Message-ID: <11c7cf6d-3ece-a25d-b424-f0467adadd0d@fu-berlin.de> Date: Mon, 4 Jul 2022 18:49:00 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0 SeaMonkey/2.53.12 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="------------E9189D12200AC3D0AE8DDCAE" X-Original-Sender: i.brunke@fu-berlin.de X-Originating-IP: 95.90.247.136 X-ZEDAT-Hint: A X-purgate: clean X-purgate-type: clean X-purgate-ID: 151147::1656953341-23B84EE9-C11DFC02/0/0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.483639, version=1.2.4 X-Spam-Flag: NO X-Spam-Status: No, score=-50.0 required=5.0 tests=ALL_TRUSTED,HTML_MESSAGE, T_SCC_BODY_TEXT_LINE X-Spam-Checker-Version: SpamAssassin 3.4.6 on Tokelau.ZEDAT.FU-Berlin.DE X-Spam-Level: Subject: [Facets-of-complexity] Invitation to Monday's Lecture & Colloquium July 11. X-BeenThere: facets-of-complexity@lists.fu-berlin.de X-Mailman-Version: 2.1.29 Precedence: list List-Id: announcements of Monday lectures and other events List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 04 Jul 2022 16:49:06 -0000 This is a multi-part message in MIME format. --------------E9189D12200AC3D0AE8DDCAE Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Dear all, next Monday's Lecture and Colloquium will take place on July 11 at 14:15 & 16:00 at TU Berlin. *You all are cordially invited. * *_Location_**: ** * *Room MA 041 - Ground Floor* Technische Universität Berlin Straße des 17. Juni 136 10623 Berlin *_Time_: **Monday, July 11 - 14:15* *_Lecture_: Bill Zwicker (Union College, USA)* *_Title_: Higher-order Condorcet cycles* *_Abstract_:* In an ordinary Condorcet cycle one can identify, for each candidate, a second candidate preferred, by a majority of voters, to the first.  In a */Condorcet cycle of order 2/* one can identify, for each pair of candidates, a third candidate preferred, by a majority of voters, to both.  We construct two Condorcet cycles of order 2.  The first, with 11 alternatives and 11 voters, improves the example of 15 alternatives and 15 voters given in [1].  The second, with 7 alternatives and 21 voters, shows that the lower bound on alternatives established in [4] and [3] (and independently in [1]) is sharp. Both our constructions use the method of */horizontal rotation/*, introduced here, which generalizes the more typical form of rotation used to construct standard Condorcet cycles. The second example also makes use of a beautifully symmetric tournament constructed in [3]. William S. Zwicker^a (joint work with Davide P. Cervone^b ) keywords: Condorcet cycle of order 2, Condorcet winning set, tournament [1] Elkind, E., Lang, J., and Saffidine, A., Condorcet Winning Sets, /Soc Choice Welf /44, 493-517 (2015) [2] Erdös, P., On a problem of graph theory, /Math Gaz/ 47, 220-223 (1963) [3] Graham, R.L. and Spencer, J.H., A constructive solution to a tournament problem, /Can Math Bul/ 14, 45-48 (1971) [4] Szekeres, E. and Szekeres,G., On a problem of Schütte and Erdös, /Math Gaz/ 49, 290-293 (1965) ^a William D Williams Professor of Mathematics Emeritus, Union College, New York; and Murat Sertel Center for Advanced Economic Studies, Istanbul Bilgi University ^b Mathematics Department, Union College, New York _*Coffee & Tea Break*_*:* *R**oom MA 316 - Third Floor* *_Time_: **Monday, July 11 **- 16:00 s.t.* *_Colloquium_: Warut Suksompong (National University of Singapore)* *_Title_: The Price of Connectivity in Fair Division* *_Abstract_:* We study the allocation of indivisible goods that form an undirected graph and quantify the loss of fairness when we impose a constraint that each agent must receive a connected subgraph. Our focus is on well-studied fairness notions including envy-freeness and maximin share fairness. We introduce the price of connectivity to capture the largest gap between the graph-specific and the unconstrained maximin share, and derive bounds on this quantity which are tight for large classes of graphs in the case of two agents and for paths and stars in the general case. For instance, with two agents we show that for biconnected graphs it is possible to obtain at least 3/4 of the maximin share with connected allocations, while for the remaining graphs the guarantee is at most 1/2. In addition, we determine the optimal relaxation of envy-freeness that can be obtained with each graph for two agents, and characterize the set of trees and complete bipartite graphs that always admit an allocation satisfying envy-freeness up to one good (EF1) for three agents. Our work demonstrates several applications of graph-theoretic tools and concepts to fair division problems. Joint work with Xiaohui Bei, Ayumi Igarashi, and Xinhang Lu. --------------E9189D12200AC3D0AE8DDCAE Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit

Dear all,

next Monday's Lecture and Colloquium will take place on July 11 at 14:15 & 16:00 at TU Berlin.

You all are cordially invited.

Location:

Room MA 041 - Ground Floor
Technische Universität Berlin
Straße des 17. Juni 136
10623 Berlin

Time: Monday, July 11 - 14:15

Lecture: Bill Zwicker (Union College, USA)

Title: Higher-order Condorcet cycles

Abstract:

In an ordinary Condorcet cycle one can identify, for each candidate, a second candidate preferred, by a majority of voters, to the first.  In a Condorcet cycle of order 2 one can identify, for each pair of candidates, a third candidate preferred, by a majority of voters, to both.  We construct two Condorcet cycles of order 2.  The first, with 11 alternatives and 11 voters, improves the example of 15 alternatives and 15 voters given in [1].  The second, with 7 alternatives and 21 voters, shows that the lower bound on alternatives established in [4] and [3] (and independently in [1]) is sharp. Both our constructions use the method of horizontal rotation, introduced here, which generalizes the more typical form of rotation used to construct standard Condorcet cycles. The second example also makes use of a beautifully symmetric tournament constructed in [3].

William S. Zwickera (joint work with Davide P. Cervoneb)

keywords: Condorcet cycle of order 2, Condorcet winning set, tournament

[1] Elkind, E., Lang, J., and Saffidine, A., Condorcet Winning Sets, Soc Choice Welf 44, 493-517 (2015)

[2] Erdös, P., On a problem of graph theory, Math Gaz 47, 220-223 (1963)

[3] Graham, R.L. and Spencer, J.H., A constructive solution to a tournament problem, Can Math Bul 14, 45-48 (1971)

[4] Szekeres, E. and Szekeres,G., On a problem of Schütte and Erdös, Math Gaz 49, 290-293 (1965)

aWilliam D Williams Professor of Mathematics Emeritus, Union College, New York; and Murat Sertel Center for Advanced Economic Studies, Istanbul Bilgi University

bMathematics Department, Union College, New York



Coffee & Tea Break :

Room MA 316 - Third Floor


Time: Monday, July 11 - 16:00 s.t.

Colloquium: Warut Suksompong (National University of Singapore)

Title: The Price of Connectivity in Fair Division

Abstract:

We study the allocation of indivisible goods that form an undirected graph and quantify the loss of fairness when we impose a constraint that each agent must receive a connected subgraph. Our focus is on well-studied fairness notions including envy-freeness and maximin share fairness. We introduce the price of connectivity to capture the largest gap between the graph-specific and the unconstrained maximin share, and derive bounds on this quantity which are tight for large classes of graphs in the case of two agents and for paths and stars in the general case. For instance, with two agents we show that for biconnected graphs it is possible to obtain at least 3/4 of the maximin share with connected allocations, while for the remaining graphs the guarantee is at most 1/2. In addition, we determine the optimal relaxation of envy-freeness that can be obtained with each graph for two agents, and characterize the set of trees and complete bipartite graphs that always admit an allocation satisfying envy-freeness up to one good (EF1) for three agents. Our work demonstrates several applications of graph-theoretic tools and concepts to fair division problems. Joint work with Xiaohui Bei, Ayumi Igarashi, and Xinhang Lu.
--------------E9189D12200AC3D0AE8DDCAE-- From itabrunke@zedat.fu-berlin.de Thu Jul 14 00:26:14 2022 Received: from outpost1.zedat.fu-berlin.de ([130.133.4.66]) by list1.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1oBko5-000fxw-Gq; Thu, 14 Jul 2022 00:26:09 +0200 Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1oBko5-001wiX-EC; Thu, 14 Jul 2022 00:26:09 +0200 Received: from [95.90.244.183] (helo=[192.168.0.2]) by inpost2.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtpsa (TLS1.3) tls TLS_AES_128_GCM_SHA256 (envelope-from ) id 1oBko1-0012t5-Na; Thu, 14 Jul 2022 00:26:09 +0200 From: Ita Brunke To: facets-of-complexity@lists.fu-berlin.de Message-ID: Date: Thu, 14 Jul 2022 00:26:06 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0 SeaMonkey/2.53.12 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="------------3148DE9D6317A94A000310CB" X-Original-Sender: i.brunke@fu-berlin.de X-Originating-IP: 95.90.244.183 X-ZEDAT-Hint: A X-purgate: clean X-purgate-type: clean X-purgate-ID: 151147::1657751169-2B8B2E82-0254887D/0/0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.002328, version=1.2.4 X-Spam-Flag: NO X-Spam-Status: No, score=-50.0 required=5.0 tests=ALL_TRUSTED,HTML_MESSAGE, T_SCC_BODY_TEXT_LINE X-Spam-Checker-Version: SpamAssassin 3.4.6 on Niue.ZEDAT.FU-Berlin.DE X-Spam-Level: Subject: [Facets-of-complexity] Invitation to Monday's Lecture & Colloquium July 18. X-BeenThere: facets-of-complexity@lists.fu-berlin.de X-Mailman-Version: 2.1.29 Precedence: list List-Id: announcements of Monday lectures and other events List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jul 2022 22:26:14 -0000 This is a multi-part message in MIME format. --------------3148DE9D6317A94A000310CB Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Dear all, our next and last Monday's Lecture and Colloquium will take place on July 18 at 14:15 & 16:00 at FU Berlin. *You are all cordially invited. * *_Location_**: ** * *Room 005 - Ground Floor* Freie Universität Berlin Takustr. 9 14195 Berlin *_Time_: **Monday, July 18 - 14:15* *_Lecture_: Herman Haverkort (Universität Bonn)* *_Title_: Space-filling curves: properties, applications and challenges* *_Abstract_:* A space-filling curve is a continuous, surjective map from [0,1] to a d-dimensional unit volume (for example, a cube or a simplex). Space-filling curves are usually constructed following a recursive tessellation of the unit volume that gives the curve useful structural properties. The most prominent of these properties is that the curve tends to preserve locality: points that are close to each other along the curve are (usually) close to each other in d-dimensional space and (usually) vice versa. This can be exploited to speed up algorithms, in practice and sometimes even in theory, by processing or storing data points in order along the curve. In this lecture I will show how space-filling curves can be described, how they get their useful properties, and I will show examples of their applications. This brings us to the question what would be the optimal space-filling curves for these applications. We will encounter a number of open questions on tessellations in 2D and 3D and on how to measure the quality of a space-filling curve. _*Coffee & Tea Break*_*:* *Room 134 - 1st Floor * *_Time_: **Monday, July 18 **- 16:00 s.t.* *_Colloquium_: Andrea Jiménez (Universidad de Varparaíso, Chile)* *_Title_: Groundstates of the Ising Model on antiferromagnetic triangulations* *_Abstract_:* We discuss a dual version of a problem about perfect matchings in cubic graphs posed by Lovasz and Plummer. The dual version is formulated as follows "Every triangulation of an orientable surface has exponentially many groundstates'', where groundstates are the states at the lowest energy in the antiferromagnetic Ising Model. According to physicists, this dual formulation holds. In this talk, I show a counterexample to the dual formulation, a method to count groundstates which gives a better bound (for the original problem) on the class of Klee-graphs, the complexity of the related problems and, if time allows, some open problems. This is joint work with Marcos Kiwi and Martin Loebl. --------------3148DE9D6317A94A000310CB Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit

Dear all,

our next and last Monday's Lecture and Colloquium will take place on July 18 at 14:15 & 16:00 at FU Berlin.

You are all cordially invited.

Location:

Room 005 - Ground Floor
Freie Universität Berlin
Takustr. 9
14195 Berlin

Time: Monday, July 18 - 14:15

Lecture: Herman Haverkort (Universität Bonn)

Title: Space-filling curves: properties, applications and challenges

Abstract:

A space-filling curve is a continuous, surjective map from [0,1] to a d-dimensional unit volume (for example, a cube or a simplex). Space-filling curves are usually constructed following a recursive tessellation of the unit volume that gives the curve useful structural properties. The most prominent of these properties is that the curve tends to preserve locality: points that are close to each other along the curve are (usually) close to each other in d-dimensional space and (usually) vice versa. This can be exploited to speed up algorithms, in practice and sometimes even in theory, by processing or storing data points in order along the curve. In this lecture I will show how space-filling curves can be described, how they get their useful properties, and I will show examples of their applications. This brings us to the question what would be the optimal space-filling curves for these applications. We will encounter a number of open questions on tessellations in 2D and 3D and on how to measure the quality of a space-filling curve.


Coffee & Tea Break :

Room 134 - 1st Floor


Time: Monday, July 18 - 16:00 s.t.

Colloquium: Andrea Jiménez (Universidad de Varparaíso, Chile)

Title: Groundstates of the Ising Model on antiferromagnetic triangulations

Abstract:

We discuss a dual version of a problem about perfect matchings in cubic graphs posed by Lovasz and Plummer. The dual version is formulated as follows "Every triangulation of an orientable surface has exponentially many groundstates'', where groundstates are the states at the lowest energy in the antiferromagnetic Ising Model.

According to physicists, this dual formulation holds. In this talk, I show a counterexample to the dual formulation, a method to count groundstates which gives a better bound (for the original problem) on the class of Klee-graphs, the complexity of the related problems and, if time allows, some open problems.

This is joint work with Marcos Kiwi and Martin Loebl.

--------------3148DE9D6317A94A000310CB-- From itabrunke@zedat.fu-berlin.de Thu Jul 14 00:34:09 2022 Received: from outpost1.zedat.fu-berlin.de ([130.133.4.66]) by list1.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1oBkvk-000h4N-AJ; Thu, 14 Jul 2022 00:34:04 +0200 Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1oBkvj-001yBq-OF; Thu, 14 Jul 2022 00:34:03 +0200 Received: from [95.90.244.183] (helo=[192.168.0.2]) by inpost2.zedat.fu-berlin.de (Exim 4.95) with esmtpsa (TLS1.3) tls TLS_AES_128_GCM_SHA256 (envelope-from ) id 1oBkvg-0013Wy-Na; Thu, 14 Jul 2022 00:34:03 +0200 To: facets-of-complexity@lists.fu-berlin.de Cc: Andrea Jimenez From: Ita Brunke Message-ID: Date: Thu, 14 Jul 2022 00:34:01 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0 SeaMonkey/2.53.12 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="------------3DA271733B18AC3E0DC96E4B" X-Original-Sender: i.brunke@fu-berlin.de X-Originating-IP: 95.90.244.183 X-ZEDAT-Hint: A X-purgate: clean X-purgate-type: clean X-purgate-ID: 151147::1657751644-7B232F4B-C2AD4C73/0/0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 X-Spam-Flag: NO X-Spam-Status: No, score=-50.0 required=5.0 tests=ALL_TRUSTED,HTML_MESSAGE, T_SCC_BODY_TEXT_LINE X-Spam-Checker-Version: SpamAssassin 3.4.6 on Niue.ZEDAT.FU-Berlin.DE X-Spam-Level: Subject: [Facets-of-complexity] Invitation to Monday's Lecture & Colloquium July 18. Program. X-BeenThere: facets-of-complexity@lists.fu-berlin.de X-Mailman-Version: 2.1.29 Precedence: list List-Id: announcements of Monday lectures and other events List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jul 2022 22:34:09 -0000 This is a multi-part message in MIME format. --------------3DA271733B18AC3E0DC96E4B Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Dear all, there may be a change of program for the colloquium. Our next and last Monday's Lecture and Colloquium will take place on July 18 at 14:15 & 16:00 at FU Berlin. *You are all cordially invited. * *_Location_**: ** * *Room 005 - Ground Floor* Freie Universität Berlin Takustr. 9 14195 Berlin *_Time_: **Monday, July 18 - 14:15* *_Lecture_: Herman Haverkort (Universität Bonn)* *_Title_: Space-filling curves: properties, applications and challenges* *_Abstract_:* A space-filling curve is a continuous, surjective map from [0,1] to a d-dimensional unit volume (for example, a cube or a simplex). Space-filling curves are usually constructed following a recursive tessellation of the unit volume that gives the curve useful structural properties. The most prominent of these properties is that the curve tends to preserve locality: points that are close to each other along the curve are (usually) close to each other in d-dimensional space and (usually) vice versa. This can be exploited to speed up algorithms, in practice and sometimes even in theory, by processing or storing data points in order along the curve. In this lecture I will show how space-filling curves can be described, how they get their useful properties, and I will show examples of their applications. This brings us to the question what would be the optimal space-filling curves for these applications. We will encounter a number of open questions on tessellations in 2D and 3D and on how to measure the quality of a space-filling curve. _*Coffee & Tea Break*_*:* *Room 134 - 1st Floor * *_Time_: **Monday, July 18 **- 16:00 s.t.* *_Colloquium_: Andrea Jiménez (Universidad de Varparaíso, Chile)* *_Title_: Grid subdivisions, wall minors and treewidth in planar graphs* *_Abstract_:* Minors, subdivisions and treewidth are classical notions that appear for example in the seminal characterization of planar graphs by Kuratowski and in the celebrated Graph Minor Theorem by Robertson and Seymour. The importance of grid/wall minors comes from one of the results of Robertson and Seymour, which roughly claims that a graph of large treewidth necessarily contains a large grid/wall minor. The concept of treewidth is fundamental in algorithmic graph theory since many problems which are hard to solve in general, can be efficiently solved when restricted to classes of graphs with bounded treewidth. In this talk, we discuss the computational complexity of the Minor Problem, the Subdivision Problem and the Treewidth Problem with input: grids/walls and planar graphs. Surprisingly, some of these problems are still open. We describe two reductions which prove that the respective GridSubdivision Problem and the WallMinor Problem are NP-complete problems. This is joint work with//Tina Janne Schmidt and with Carla Lintzmayer and Maycon Sambinelli. --------------3DA271733B18AC3E0DC96E4B Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit

Dear all,

there may be a change of program for the colloquium.

Our next and last Monday's Lecture and Colloquium will take place on July 18 at 14:15 & 16:00 at FU Berlin.

You are all cordially invited.

Location:

Room 005 - Ground Floor
Freie Universität Berlin
Takustr. 9
14195 Berlin

Time: Monday, July 18 - 14:15

Lecture: Herman Haverkort (Universität Bonn)

Title: Space-filling curves: properties, applications and challenges

Abstract:

A space-filling curve is a continuous, surjective map from [0,1] to a d-dimensional unit volume (for example, a cube or a simplex). Space-filling curves are usually constructed following a recursive tessellation of the unit volume that gives the curve useful structural properties. The most prominent of these properties is that the curve tends to preserve locality: points that are close to each other along the curve are (usually) close to each other in d-dimensional space and (usually) vice versa. This can be exploited to speed up algorithms, in practice and sometimes even in theory, by processing or storing data points in order along the curve. In this lecture I will show how space-filling curves can be described, how they get their useful properties, and I will show examples of their applications. This brings us to the question what would be the optimal space-filling curves for these applications. We will encounter a number of open questions on tessellations in 2D and 3D and on how to measure the quality of a space-filling curve.


Coffee & Tea Break :

Room 134 - 1st Floor


Time: Monday, July 18 - 16:00 s.t.

Colloquium: Andrea Jiménez (Universidad de Varparaíso, Chile)

Title: Grid subdivisions, wall minors and treewidth in planar graphs

Abstract:

Minors, subdivisions and treewidth are classical notions that appear for example in the seminal characterization of planar graphs by Kuratowski and in the celebrated Graph Minor Theorem by Robertson and Seymour. The importance of grid/wall minors comes from one of the results of Robertson and Seymour, which roughly claims that a graph of large treewidth necessarily contains a large grid/wall minor. The concept of treewidth is fundamental in algorithmic graph theory since many problems which are hard to solve in general, can be efficiently solved when restricted to classes of graphs with bounded treewidth.

In this talk, we discuss the computational complexity of the Minor Problem, the Subdivision Problem and the Treewidth Problem with input: grids/walls and planar graphs. Surprisingly, some of these problems are still open. We describe two reductions which prove that the respective GridSubdivision Problem and the WallMinor Problem are NP-complete problems.

This is joint work with Tina Janne Schmidt and with Carla Lintzmayer and Maycon Sambinelli.
--------------3DA271733B18AC3E0DC96E4B-- From szabo@zedat.fu-berlin.de Thu Sep 22 12:06:29 2022 Received: from outpost1.zedat.fu-berlin.de ([130.133.4.66]) by list1.zedat.fu-berlin.de (Exim 4.95) for facets-of-complexity@lists.fu-berlin.de with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (envelope-from ) id 1obJ68-000UYk-Ld; Thu, 22 Sep 2022 12:06:24 +0200 Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1obJ68-002f0C-Ho; Thu, 22 Sep 2022 12:06:24 +0200 Received: from ip5f5aeaf2.dynamic.kabel-deutschland.de ([95.90.234.242] helo=[192.168.0.8]) by inpost2.zedat.fu-berlin.de (Exim 4.95) with esmtpsa (TLS1.3) tls TLS_AES_128_GCM_SHA256 (envelope-from ) id 1obJ68-001PJy-Ba; Thu, 22 Sep 2022 12:06:24 +0200 Content-Type: multipart/alternative; boundary="------------mcYTkca8NEGbD2Z1TcmIiEuE" Message-ID: Date: Thu, 22 Sep 2022 12:06:23 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:91.0) Gecko/20100101 Thunderbird/91.13.0 Content-Language: en-US From: Tibor Szabo To: facets-of-complexity@lists.fu-berlin.de, m-profs@math.fu-berlin.de, i-prof@inf.fu-berlin.de, m-wimis@math.fu-berlin.de, i-wimi@inf.fu-berlin.de Cc: Olaf Parczyk , Sabrina Nordt , =?UTF-8?Q?Let=c3=adcia_Mattos?= References: <3ccff1fb-a2d2-6b82-3b7f-d84fc31f8f1c@zedat.fu-berlin.de> <89eedbfd-db19-8a0d-3f4e-90d7cb5c756d@zedat.fu-berlin.de> In-Reply-To: <89eedbfd-db19-8a0d-3f4e-90d7cb5c756d@zedat.fu-berlin.de> X-Originating-IP: 95.90.234.242 X-ZEDAT-Hint: A X-purgate: clean X-purgate-type: clean X-purgate-ID: 151147::1663841184-BFB59D5B-43C6D654/0/0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.009103, version=1.2.4 X-Spam-Flag: NO X-Spam-Status: No, score=-50.0 required=5.0 tests=ALL_TRUSTED,HTML_MESSAGE X-Spam-Checker-Version: SpamAssassin 3.4.6 on Niue.ZEDAT.FU-Berlin.DE X-Spam-Level: X-Mailman-Approved-At: Thu, 22 Sep 2022 12:10:00 +0200 Subject: [Facets-of-complexity] Aigner 80 X-BeenThere: facets-of-complexity@lists.fu-berlin.de X-Mailman-Version: 2.1.29 Precedence: list List-Id: announcements of Monday lectures and other events List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Sep 2022 10:06:29 -0000 This is a multi-part message in MIME format. --------------mcYTkca8NEGbD2Z1TcmIiEuE Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Dear Colleagues, in 2022 Martin Aigner has turned 80. On the afternoon (14:00-18:00) of the 7th of November we will celebrate this occasion with a Festkolloquium. Invited speakers include Mathias Schacht (Hamburg), Emo Welzl (Zurich), and Günther Ziegler (Berlin). There is no registration fee, however, if you are interested in attending, please indicate this *by the end of September:* **https://docs.google.com/forms/d/e/1FAIpQLSfEsxz0FD9RDZQT2PosE86UD-HFHjgGFDBQTE8hvD4ETsb-dg/viewform so we can estimate the number of participants. Best regards, Tibor Szabó --------------mcYTkca8NEGbD2Z1TcmIiEuE Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit

Dear Colleagues,

in 2022 Martin Aigner has turned 80. On the afternoon (14:00-18:00) of the 7th of November we will celebrate this occasion with a Festkolloquium. Invited speakers include Mathias Schacht (Hamburg), Emo Welzl (Zurich), and Günther Ziegler (Berlin). There is no registration fee, however, if you are interested in attending, please indicate this by the end of September:

https://docs.google.com/forms/d/e/1FAIpQLSfEsxz0FD9RDZQT2PosE86UD-HFHjgGFDBQTE8hvD4ETsb-dg/viewform

so we can estimate the number of participants.

Best regards,

Tibor Szabó

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