2024
- Special Session on Singularities, Joint Meeting of the NZMS, AustMS, and AMS, Auckland, New Zealand, December 9–13, 2024.
- Workshop on Polyhedral Products, Fields Institute, Toronto, July 29–August 2, 2024.
- Suzhou Workshop on Matroid Theory, Soochow University, Suzhou, China, July 8–12, 2024.
- Workshop on Arrangements, matroids and logarithmic vector fields, Mathematisches Forshungsinstitut, Oberwolfach, Germany, June 16–21, 2024.
- Cohomology jump loci in geometry and topology
Master class on Hodge theory and cohomological jump loci, Stockholm University and KTH, Sweden, May 27–31, 2024. - Artin kernels and Milnor fibrations of arrangements
Workshop on Artin groups and arrangements: topology, geometry, and combinatorics, SLMath, Berkeley, CA, March 11–15, 2024. [abstract] [slides] [video] - On the geometry and topology of polynomials
Representation Theory and Related Topics Seminar, Northeastern University, February 23, 2024. [announcement] [slides]
2023
- On the topology and combinatorics of decomposable arrangements
Topology Seminar, Osaka University, December 20, 2023. [announcement] [slides] - Hyperplane arrangements with trivial algebraic monodromy
Hyperplane Arrangements 2023, Rykkio University, Tokyo, Japan, December 11–15, 2023. [slides] - Resonance schemes of simplicial complexes
GASC Seminar, Northeastern University, September 11, 2023. [slides] - Lower central series and Alexander invariants in group extensions
Moduli and Friends Seminar, IMAR, Bucharest, Romania, July 26, 2023. [slides] - Conference on Geometry, Topology and Algebra of Singular Spaces, IMAR, Bucharest, Romania, July 7–11, 2023.
- Towards an integral version of rational homotopy theory
The Tenth Congress of Romanian Mathematicians, Pitești, Romania, July 1, 2023. [slides] - Topology of hyperplane arrangements
Research School on Singularities and Applications, University of Lille, France, June 23, 2023. [extended abstract] [slides] - The work of Enrique Artal Bartolo on the topology of singularities
Conference on Algebraic and topological interplay of algebraic varieties, Jaca, Spain, June 14, 2023. [slides] - Resonance schemes, Koszul modules, and Hilbert series
Topology Seminar, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, May 26, 2023. [announcement] [slides] - Poincaré duality algebras and resonance varieties
Maurice Auslander International Conference, Woods Hole, MA, April 27, 2023. [slides] - Resonance schemes and Hilbert series for Koszul modules
MIT-Harvard-MSR Combinatorics Seminar, Harvard University, April 26, 2023. [announcement] [slides] - Tropical bounds for the Bieri-Neumann-Strebel-Renz invariants
Geometric Group Theory and Topology Seminar, Tufts University, April 11, 2023. [slides] - Algebra and topology of group extensions
Algebra and Topology Seminar, University of Strasbourg, France, March 28, 2023. [slides] - Tropical bounds for the BNSR invariants
Algebraic Topology Seminar, UC Louvain, Belgium, March 22, 2023. [slides] - Lie algebras associated to hyperplane arrangements
Workshop on Various guises of reflection arrangements, International Centre for Mathematical Sciences, Edinburgh, UK, March 14, 2023. [slides] - Poincaré duality and resonance
Pure Math Seminar, University of New South Wales Sydney, Australia, February 23, 2023. [announcement][slides] - Topological invariants of groups and tropical geometry
Recent Progress in Mathematics and Statistics Seminar, University of Sydney, Australia, February 9, 2023. [announcement] [slides]
2022
- Cohomology jump loci, Poincaré duality, and Pfaffians
Workshop on Pfaffians, tensors, and applications, Max Planck Institute for Mathematics in the Sciences, Leipzig, Germany, November 30, 2022. [slides] - Polyhedral products, duality properties, and cohomology jump loci
Discrete Geometry and Topological Combinatorics Seminar, Freie University Berlin, Germany, November 25, 2022. [slides] - Topological invariants of groups and tropical geometry
Algebraic Geometry Seminar, Humboldt University Berlin, Germany, November 23, 2022. [slides] - Resonance varieties of differential graded algebras
Conference on Resonance, topological invariants of groups, moduli, Humboldt University Berlin, Germany, November 18, 2022. [slides] - Cohomology, Bocksteins, and resonance
Topology Seminar, Northeastern University, Boston, MA, September 27, 2022. - Arrangements and lower central series
Arrangements in Ticino, Università della Svizzera italiana, July 1, 2022. [slides] - Alexander invariants of commutative differential graded algebras
Algebraic Geometry and Algebraic Topology Seminars, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, April 7, 2022. - Cohomology jump loci of 3-dimensional manifolds
Colloquium, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, April 6, 2022. [announcement] [slides] - Arrangements, duality, and local systems
Workshop on Braids in symplectic and algebraic geometry, at ICERM, Brown University, Providence, RI, March 24, 2022. [slides] - Cohomology jump loci of 3-dimensional manifolds
Topology Seminar, University of Michigan, February 24, 2022. [slides] - Alexander invariants of algebraic models for spaces
Graduate/Postdoc Topology and Singularities Seminar, University of Wisconsin-Madison, February 7, 2022.
2021
- Braids, configurations, and polynomials
Math Club, Northeastern University, December 3, 2021. [flyer] - Braids and line arrangements—old and new
Conference on Braids, Links, and Applications, Institute of the Mathematical Sciences of the Americas, University of Miami, November 15, 2021. [slides] - Braids and configuration spaces
Playing with Braids, Institute of the Mathematical Sciences of the Americas, University of Miami, November 14, 2021. [slides] - Duality, finiteness, and cohomology jump loci [slides]
The work of Alexandru Dimca in algebra, geometry, and topology [slides]
Conference in Algebraic Geometry for Alexandru Dimca’s retirement, Ischia, Italy, October 11–14, 2021. - On the topology of Milnor fibrations of hyperplane arrangements
TIBĂR60 Conference, University of Wisconsin-Madison, September 11, 2021. [video] [slides] - Algebra and topology of group extensions. Part II.
Topology Seminar, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, July 2, 2021. [slides] - Algebra and topology of group extensions. Part I.
Topology Seminar, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, June 25, 2021. [slides] - Tropical upper bounds for the BNSR invariants
Topology Seminar, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, May 21, 2021. [slides] - Finiteness properties, cohomology jump loci, and tropical varieties
Topology Seminar, Northeastern University, Boston, MA, April 13, 2021. [announcement] [slides] - Ab-exact extensions and Milnor fibrations of arrangements
Graduate/Postdoc Topology and Singularities Seminar, University of Wisconsin-Madison, February 15, 2021. [slides] - Milnor fibrations of arrangements with trivial algebraic monodromy
Workshop on Logarithmic Vector Fields and Freeness of Divisors and Arrangements, Mathematisches Forshungsinstitut, Oberwolfach, Germany, January 24-30, 2021. [slides]
2020
- Sigma-invariants and tropical geometry
Online Geometry and Combinatorics Seminar, University of Western Ontario, London, ON, Canada, September 28, 2020. [slides] - Poincaré duality and cohomology jump loci
Online Algebraic Geometry Seminar, Humboldt University, Berlin, Germany, July 15, 2020. [slides] - Workshop on Geometry, Combinatorics and Representation Theory, Soochow University, Suzhou, China, July 6-9, 2020. [Cancelled due to COVID-19]
- Summer School and Workshop on Arrangements, University of Fribourg, Switzerland, June 25-July 3, 2020. [Cancelled due to COVID-19]
- Workshop on Configuration Spaces of Graphs, American Institute of Mathematics, San Jose, CA, February 3-7, 2020.
- Finiteness and formality obstructions
Workshop on Polyhedral Products in Homotopy Theory, The Fields Institute, Toronto, ON, January 21, 2020. [slides]
2019
- Sigma-invariants, cohomology jump loci, and tropicalization
Hyperplane Arrangements and Singularities, University of Tokyo, Japan, December 2, 2019. [slides] - Poincaré duality and resonance varieties
GASC Seminar, Northeastern University, November 25, 2019. [slides] - BNSR-invariants and tropical varieties
Special Session on Geometry and Topology of Singularities, AMS Fall Central Sectional Meeting, University of Wisconsin, Madison, WI, September 14, 2019. [slides] - Cohomology jump loci in geometry and topology
Donu Arapura’s 60th Birthday Conference, University of Wisconsin, Madison, WI, September 12, 2019. [slides] - Germs of representation varieties and cohomology jump loci
Conference on Non-Isolated Singularities and Derived Geometry, UNAM-Cuernavaca, Mexico, August 1, 2019. [slides] - Duality, finiteness, and cohomology jump loci
Colloquium, University of Notre Dame, April 5, 2019. [poster] [slides] - Arrangement groups, lower central series, and Massey products
Workshop at the CIMPA Research School on Hyperplane Arrangements, Institute of Mathematics, Vietnam Academy of Science and Technology, Hanoi, Vietnam, March 22, 2019. [slides] - Topology and combinatorics of hyperplane arrangements
Colloquium, University of Nevada at Reno, February 22, 2019. [slides] - Braids, hyperplane arrangements, and Milnor fibrations
Workshop on Braids, Resolvent Degree and Hilbert’s 13th Problem, Institute for Pure and Applied Mathematics, UCLA, Los Angeles, CA, February 21, 2019. [video] [slides]
2018
- On the topology of complex line arrangements
Conference on Knotted Surfaces in 4-Manifolds, University of Massachusetts Amherst, October 27, 2018. - Geometry and topology of cohomology jump loci (3 lectures)
Summer School: New Trends in Topology and Geometry, Mediterranean Institute for the Mathematical Sciences, Tunis, Tunisia, July 9-12, 2018. [lecture 1] [lecture 2] [lecture 3] - Cohomology jump loci and duality properties
Topology Seminar, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, June 1, 2018. [slides] - The work of Stefan Papadima in topology and geometry
Topology and Geometry: A conference in memory of Stefan Papadima, Institute of Mathematics of the Romanian Academy, Bucharest, Romania, May 28, 2018. [slides] - Duality and cohomology jump loci
Geometry & Topology Seminar, University of Western Ontario, London, ON, Canada, May 21, 2018. [slides] - Abelian duality spaces
Special Session on Algebraic, Geometric and Topological Methods in Combinatorics, AMS Spring Eastern Sectional Meeting, Northeastern University, Boston, MA, April 21, 2018. [slides] - Algebraic models, duality, and resonance
Topology Seminar, MIT, March 5, 2018. [slides]
2017
- Duality and resonance
Topology Seminar, University of Rochester, Rochester, NY, November 8, 2017. [announcement] [slides] - Geometric and homological finiteness properties
Mini-Workshop on Interactions between low-dimensional topology and complex algebraic geometry, Mathematisches Forshungsinstitut, Oberwolfach, Germany, October 27, 2017. [slides] - Algebraic models, cohomology jump loci, and finiteness properties
Topology Seminar, University of California, Berkeley, Berkeley, CA, October 11, 2017. [announcement] [slides] - A quick introduction to cohomology jump loci
Topology Seminar, University of California, Berkeley, Berkeley, CA, October 11, 2017. [announcement] [slides] - Poincaré duality, abelian duality, and resonance
Geometry and Topology Seminar, San Francisco State University, San Francisco, CA, October 6, 2017. [announcement] [slides] - Resonance varieties for matroids
Thematic week Matroids in Boston, Northeastern University, Boston, MA, September 13, 2017 - Polyhedral products, duality properties, and Cohen-Macaulay complexes
Special Session on Geometry and Combinatorics of Cell Complexes, Mathematical Congress of the Americas, Montréal, Canada, July 28, 2017. [abstract] [slides] - Arrangement complements and Milnor fibrations
Special Session on Advances in Arrangement Theory, Mathematical Congress of the Americas, Montréal, Canada, July 25, 2017. [abstract] [slides] - Formality notions for spaces and groups
Workshop on Nilpotent Fundamental Groups, Banff International Research Station, Alberta, Canada, June 22, 2017. [slides] [video] - Duality and resonance
Colloquium, University of Bremen, Germany, June 13, 2017 [announcement] [slides] - Resonance varieties
Summer School and Workshop ET’nA 2017: Encounter in Topology and Algebra, Scuola Superiore di Catania, Italy, May 31, 2017. [slides] - Algebraic invariants of pure braid-like groups
Workshop on Braids in Algebra, Geometry, and Topology, International Centre for Mathematical Sciences, Edinburgh, UK, May 23, 2017. [slides] - Representation varieties and polyhedral products
Special Session on Representation Spaces and Toric Topology, AMS Spring Eastern Sectional Meeting, Hunter College, CUNY, New York, NY, May 6, 2017 [slides] - Representation varieties and cohomology jump loci
Singularities in the Midwest, IV, University of Wisconsin, March 17, 2017. [slides]
2016
- On the topology of line arrangements
Summer Conference on Hyperplane Arrangements, at Hokkaido University, Sapporo, Japan, August 8-12, 2016. [slides] - The pure braid groups and their relatives
Topology Seminar, Mathematics Institute of the Romanian Academy, Bucharest, Romania, June 17, 2016. [slides] - An introduction to resonance varieties (2 lectures)
Doctoral School and Workshop on Topology and Geometry of Arrangements, University of Fribourg, Switzerland, June 8, 2016. - Fundamental groups in algebraic geometry and three-dimensional topology
Colloquium, University of Fribourg, Switzerland, June 7, 2016. [announcement] [poster] [slides] - Residual finiteness properties of fundamental groups
Number Theory and Algebraic Geometry Seminar, KU Leuven, Belgium, May 18, 2016. [abstract] [slides] - Fundamental groups in complex geometry and 3-dimensional topology
Topology Seminar, Brandeis University, March 29, 2016. [abstract] [slides] - Algebraic models for Sasakian manifolds and weighted-homogeneous surface singularities
Workshop on Singularities and Topology, at Université de Nice, France, March 7-9, 2016. [abstract] [slides] - The pure braid groups and their relatives
Algebra and Geometry Seminar, University of Caen, France, January 5, 2016. [slides]
2015
- Complex geometry and 3-dimensional topology
Workshop on Geometric Group Theory and Geometric Topology, at the University of Virginia, Charlottesville, VA, October 17, 2015. [slides] - Group actions on manifolds and formality properties
30th British Topology Meeting, at Queen’s University Belfast, Belfast, Northern Ireland, UK, September 8, 2015. - Sigma-invariants and tropical varieties
Conference on Finiteness Conditions in Topology and Algebra, at Queen’s University Belfast, Belfast, Northern Ireland, UK, September 1, 2015. [slides] - Hyperplane arrangements: at the crossroads of topology and combinatorics
PIMS Distinguished Lecture, University of Regina, Saskatchewan, Canada, August 14, 2015. [announcement] [slides] - Hyperplane arrangements: Cohomology jump loci and Milnor fibrations
Workshop on Computational Geometric Topology in Arrangement Theory, at ICERM, Brown University, Providence, RI, July 6-10, 2015. Talk 1: [slides] [video]. Talk 2: [slides] [video]. - Topology of complex arrangements
The Eighth Congress of Romanian Mathematicians, Iași, Romania, June 30, 2015 [slides] - Deconstructing formality
Topology Seminar, Mathematics Institute of the Romanian Academy, Bucharest, Romania, June 19, 2015 [abstract] - Hyperplane arrangements and Milnor fibrations
Geometry & Topology Seminar, University of Western Ontario, London, ON, Canada, June 1, 2015 [slides] - Resonance, representations, and the Johnson filtration
Geometry/Topology Seminar, University of Chicago, May 8, 2015 [slides] - Geometry and topology of cohomology jump loci (8 lectures)
Geometric Literacy course, University of Chicago, April 20-May 8, 2015. - Algebraic models and the Tangent Cone theorem
Representation Theory and Related Topics Seminar, Northeastern University, April 10, 2015 [abstract] [slides] - Fundamental groups in topology and geometry
Math Club Lecture Series, Northeastern University, March 26, 2015 - Algebraic models and cohomology jump loci
Intensive research period on Algebraic Topology, Geometric and Combinatorial Group Theory, at the Centro di Ricerca Matematica Ennio De Giorgi, Pisa, Italy, February 24, 2015 [announcement] [slides]
2014
- Topology of line arrangements
Conference on Configuration Spaces–Geometry, Topology and Representation Theory, Palazzone di Cortona, Italy, September 1, 2014 [slides] - Combinatorial covers, abelian duality, and propagation of resonance
Conference on Topology of Torus Actions and Applications to Geometry and Combinatorics, Korea Advanced Institute of Science and Technology, Daejeon, Korea, August 7, 2014 [video] [slides] - Complex geometry and three-dimensional topology
Algebra and Geometry Seminar, University of Caen, France, June 17, 2014. [slides] - Hyperplane arrangements, Milnor fibrations, and boundary manifolds
Algebra, Geometry and Topology Seminar, Université de Nice, France, June 10, 2014. [slides] - Combinatorial covers, abelian duality, and propagation of resonance
Algebra, Topology and Combinatorics Seminar, Università di Pisa, Italy, May 29, 2014. [slides] - Topology of hyperplane arrangements
Baby Geometry Seminar, Università di Pisa, Italy, May 28, 2014. [slides] - Milnor fibrations of hyperplane arrangements
Focused Research Group on Hyperplane Arrangements, Wonderful Compactifications, and Tropicalization, Banff International Research Station, Alberta, Canada, April 20, 2014. [slides] - Homological finiteness in the Johnson filtration
Geometry & Topology Seminar, Yale University, February 4, 2014. [slides] - Abelian duality and propagation of resonance
Special Session on Hyperplane Arrangements and Applications, Joint Mathematics Meetings, Baltimore, MD, January 14, 2014 [abstract] [slides]
2013
- Milnor fibrations of hyperplane arrangements
Geometry Colloquium, Hokkaido University, Sapporo, Japan, November 22, 2013. [slides] - Topology and combinatorics of Milnor fibrations of hyperplane arrangements
Conference on Hyperplane Arrangements and Characteristic Classes, Research Institute for Mathematical Sciences, Kyoto, Japan, November 13, 2013 [slides] - Complex geometry and low-dimensional topology
Geometry and Topology Seminar, Max Planck Institute for Mathematics, Bonn, Germany, October 28, 2013. [abstract] [slides] - Hyperplane arrangements: at the crossroads of topology and combinatorics
Colloquium, Goethe University Frankfurt, Germany, October 25, 2013 [slides] - Milnor fibrations of hyperplane arrangements
Colloquium, University of Bremen, Germany, October 22, 2013 [slides] - Topology and geometry of cohomology jump loci
Conference on Experimental and Theoretical Methods in Algebra, Geometry and Topology, Eforie Nord, Romania, June 24, 2013 [slides] - Milnor fibrations of hyperplane arrangements
Algebraic Geometry and Topology Seminars, Mathematics Institute of the Romanian Academy, Bucharest, Romania, June 14, 2013 [announcement] [slides] - Automorphism groups, Lie algebras, and resonance varieties
Colloquium, University of Western Ontario, London, ON, Canada, April 25, 2013 [slides] - Multinets, parallel connections, and Milnor fibrations of arrangements
Special Session on Singular Spaces in Geometry, Topology, and Algebra, AMS Spring Western Sectional Meeting, Boulder, CO, April 14, 2013 [abstract] [slides]
2012
- Complex geometry and 3-dimensional topology
GTA Mini-Workshop on Geometry and Topology, University of Sydney, December 10, 2012 [abstract] [slides] - The rational homology of smooth real toric varieties
Geometry Topology and Analysis Seminar, University of Sydney, November 26, 2012 [abstract] [slides] - The rational homology of real toric manifolds
Mini-Workshop on Cohomology Rings and Fundamental Groups of Hyperplane Arrangements, Wonderful Compactifications, and Real Toric Varieties, Mathematisches Forshungsinstitut, Oberwolfach, Germany, October 5, 2012 [extended abstract] - Resonance varieties
Mini-Workshop on Cohomology Rings and Fundamental Groups of Hyperplane Arrangements, Wonderful Compactifications, and Real Toric Varieties, Mathematisches Forshungsinstitut, Oberwolfach, Germany, October 2, 2012 [extended abstract] - Resonance and representations
GASC Seminar, Northeastern University, September 17, 2012 [abstract] - Moment-angle complexes, toric manifolds, and twisted cohomology
Topology Seminar, Mathematics Institute of the Romanian Academy, Bucharest, Romania, June 22, 2012 [slides] - Topology of Milnor fibrations of hyperplane arrangements (3 lectures)
School and Workshop on Hyperplane Arrangements and Related Topics, University of Pau, Pau, France, June 11-15, 2012 - Green-Lazarsfeld sets and the topology of smooth algebraic varieties
Workshop on Singularities of Differential Equations in Algebraic Geometry, Centre International de Rencontres Mathématiques, Luminy, France, June 8, 2012 [slides] - The rational cohomology of smooth, real toric varieties
Workshop on Arrangements and Configuration Spaces, University of Bremen, Bremen, Germany, May 25, 2012 [slides] - Fundamental groups and cohomology jumping loci
Geometric Topology Seminar, Max Planck Institute for Mathematics, Bonn, Germany, May 7, 2012 [abstract] - Polyhedral products, quasi-toric manifolds, and twisted cohomology
Princeton–Rider workshop on Homotopy Theory and Toric Spaces, Princeton University, February 23, 2012 [abstract] [slides] - Sigma invariants of hyperplane arrangements
Colby-Bates-Bowdoin Collaborative Conference on Geometry, Topology, and Group Theory, Bates College, Lewiston, ME, January 10, 2012 - Geometric and homological finiteness in free abelian covers
Special Session on Geometric Invariants of Groups and Related Topics, Joint Mathematics Meetings, Boston, MA, January 7, 2012 [abstract] [slides]
2011
- The rational cohomology of real quasi-toric manifolds
Conference on Toric Methods in Homotopy Theory, Queen’s University Belfast, Northern Ireland, UK, July 20, 2011 [slides] - Homological finiteness in the Andreadakis-Johnson filtration
Algebra and Geometry Seminar, University of Caen, June 21, 2011. [slides] - The algebra and topology of partial products of circles
Groups and Braids Seminar, University of Caen, June 8, 2011 [slides] - Abelian Galois covers and rank one local systems
Topology of Algebraic Varieties, Université de Nice, France, May 25, 2011 [slides] - Betti numbers of abelian covers
Geometry and Topology Seminar, University of Wisconsin, May 6, 2011 [abstract] [slides] - On the Johnson filtration of the automorphism group of a free group
Mathematics Seminar Series, U. Mass Boston, March 30, 2011 [abstract] [slides] - Betti numbers of abelian covers
Alumni Conference, Northeastern University, March 12, 2011
2010
- Dwyer-Fried invariants
The Worldwide Center of Mathematics, Cambridge, MA, July 9, 2010 [poster] [video] - Free abelian covers and arrangements of Schubert varieties
Workshop on combinatorial and geometric aspects of Hyperplane Arrangements, Centro di Ricerca Matematica Ennio De Giorgi, Pisa, Italy, May 25, 2010 [abstract] [slides] - Cohomology jumping loci and homological finiteness properties
Intensive research period on Configuration Spaces: Geometry, Combinatorics and Topology, Centro di Ricerca Matematica Ennio De Giorgi, Pisa, Italy, May 10-14, 2010 [lecture 1] [lecture 2] [lecture 3] - Topological methods in geometry, algebra, singularities, and combinatorics
Alumni Conference, Northeastern University, March 20, 2010 - Homological finiteness and the incidence correspondence
GASC Seminar, Northeastern University, February 22, 2010 [abstract]
2009
- Geometry and topology of cohomology jumping loci
Colloquium, University at Albany, December 4, 2009 [announcement] [slides] - How to compute the homology of the Milnor fibre of a non-isolated weighted homogeneous singularity
Singularities Seminar, University of Warwick, United Kingdom, November 23, 2009 - Cohomology jump loci, Sigma-invariants, and fundamental groups of algebraic varieties
Topology Seminar, University of Oxford, United Kingdom, November 16, 2009 [announcement] [slides] - The Alexander polynomial and its friends
Geometry and Topology Seminar, University of Warwick, United Kingdom, November 5, 2009 [abstract] - Fundamental groups of smooth, (quasi-) projective varieties
Singularity Day, University of Warwick, United Kingdom, November 4, 2009 - Algebra and topology of right-angled Artin groups
Algebra Seminar, University of Leeds, United Kingdom, October 19, 2009 [slides] - Partial products of circles
Algebra and Geometry Seminar, VU University Amsterdam, The Netherlands, October 13, 2009 [slides] - Fundamental groups and cohomology support loci
Colloquium, University of Liverpool, United Kingdom, October 2, 2009 [slides] - On the geometry and topology of cohomology jump loci
MSJ Seasonal Institute on Arrangements of Hyperplanes, Hokkaido University, Sapporo, Japan, August 9, 2009 [slides] - Characteristic varieties and homological finiteness properties
LIB60BER – Topology of Algebraic Varieties, Jaca, Spain, June 24, 2009 [abstract] [slides] - Jump loci and homological finiteness properties
Workshop on Fundamental Groups in Algebraic Geometry, Université de Nice, France, May 26, 2009 - Introduction to toric topology (with Alvise Trevisan)
Tapas Seminar, Northeastern University, May 14, 2009 - A look at polyhedral products
Special Session on Topological Robotics, AMS Spring Eastern Section Meeting, Worcester, MA, April 24, 2009 [abstract]
2008
- Geometry and topology of cohomology jumping loci
Topology Seminar, CUNY Graduate Center, November 20, 2008 - Finiteness properties of groups and homology jumping loci
GASC Seminar, Northeastern University, October 27, 2008 [abstract] - Bieri-Neumann-Strebel-Renz invariants and homology jumping loci
Special Session on Low-Dimensional Topology, AMS Fall Eastern Section Meeting, Middletown, CT, October 12, 2008 [abstract] - Cohomology jumping loci
Topology Seminar, MIT, October 6, 2008 - Spectral sequences and homology with local coefficients
Conference in honour of Peter Orlik, Fields Institute, Toronto, ON, August 19, 2008 [abstract ] [audio] - Which Kähler groups are 3-manifold groups?
International Conference in Algebraic Geometry, Mathematics Institute of the Romanian Academy, Bucharest, Romania, July 3, 2008 [abstract] [slides] - Polyhedral products
Tapas Seminar, Northeastern University, June 19, 2008 [abstract] [slides] - Topology and combinatorics of polyhedral products
Algebra and Geometry Seminar, Stockholm University, Sweden, June 5, 2008 [announcement] [slides] - Minimal models in algebra, combinatorics and topology
Report on the Ph.D. Thesis of Alexander Berglund, Stockholm University, Sweden, June 3, 2008 [announcement] - Homotopy-type invariants of polyhedral products
Algebraic Topology Seminar, Université Catholique de Louvain, Louvain la Neuve, Belgium, May 27, 2008 - Which 3-manifold groups are Kähler groups?
Special Session on Arrangements and Related Topics, AMS Spring Southeastern Meeting, Baton Rouge, LA, March 29, 2008 [abstract] [slides]
2007
- Which Kähler groups are 3-manifold groups?
Analysis and Geometry Seminar, Northeastern University, November 30, 2007 [abstract] - Cohomology jumping loci and quasi-projective varieties
Topology Seminar, Mathematics Institute of the Romanian Academy, Bucharest, Romania, October 12, 2007 [announcement] - The topology of the boundary manifold of a projective hypersurface
D-Modules and Singularities Seminar, Université de Nice, France, September 27, 2007 - Generalized moment angle complexes
Algebra and Topology Seminar, Université de Nice, France, September 24, 2007 - The equivariant spectral sequence and cohomology with local coefficients
Mini-Workshop on Topology of Closed One-Forms and Cohomology Jumping Loci, Mathematisches Forshungsinstitut, Oberwolfach, Germany, August 16, 2007 [extended abstract] - Jumping loci and finiteness properties of groups
Mini-Workshop on Topology of Closed One-Forms and Cohomology Jumping Loci, Mathematisches Forshungsinstitut, Oberwolfach, Germany, August 13, 2007 [extended abstract] - Fundamental groups and geometry
Tapas Seminar, Northeastern University, June 6, 2007 - Quasi-projective Bestvina-Brady groups
Conference on Braids and their Ramifications, Palazzone di Cortona, Italy, May 23, 2007 [abstract] [slides] - Cohomology support loci, formality, and fundamental groups of quasi-projective varieties
Colloquium, Purdue University, West Lafayette, IN, March 7, 2007 [abstract] - Cohomology jumping loci
Alumni Conference, Northeastern University, February 24, 2007
2006
- Some combinatorial constructions in topology and group theory
Topology Seminar, Università di Pisa, Italy, November 9, 2006 - Boundary manifolds of complex hypersurfaces
Math Seminar, ICTP, Trieste, Italy, November 6, 2006 [announcement] - Fundamental group computations in the theory of arrangements and related spaces
Workshop on Topological Methods in Combinatorics, Computational Geometry, and the Study of Algorithms, MSRI, Berkeley, CA, October 2, 2006 [video] - Cohomology jumping loci and fundamental groups of projective varieties
Topology Seminar, University of Oregon, Eugene, OR, September 25, 2006 [abstract] - Cohomology jumping loci, formality, and quasi-projectivity
Workshop on Recent Developments in Arrangements and Configuration Spaces, MSRI, Berkeley, CA, August 8, 2006 [video]
2005
- Configuration spaces and non-formality
Algebra Seminar, University of Western Ontario, London, ON, Canada, November 21, 2005 - Boundary manifolds of complex projective hypersurfaces
GASC Seminar, Northeastern University, November 7, 2005 [abstract] - On the algebra and topology of right-angled Artin groups
Algebraic Topology Seminar, Université Catholique de Louvain, Louvain la Neuve, Belgium, October 24, 2005 - Algebraic invariants for Bestvina-Brady groups
Hyperplane Arrangements Workshop, Pacific Institute for the Mathematical Sciences, Vancouver, Canada, August 21, 2005 - Free partially commutative groups and Lie algebras
Arrangements of Hyperplanes – Algebra, Combinatorics, Geometry, and Topology, Ascona, Switzerland, May 19, 2005 [abstract] - Configuration spaces and embedding obstructions (with David Wilson)
Tapas Seminar, Northeastern University, May 11, 2005 - Borsuk-Ulam theorem and applications (with Marcus Fries)
Tapas Seminar, Northeastern University, May 9, 2005 [notes] - Graphs, groups, and polynomials (with Marcus Fries)
Research & Technology Expo 2005, Northeastern University, March 16, 2005 - Graphs, groups, and cohomology
GASC Seminar, Northeastern University, February 14, 2005 [abstract]
2004
- A look at right-angled Artin groups
Workshop on Combinatorial Aspects of Hyperplane Arrangements, MSRI, Berkeley, CA, November 5, 2004 [video] - Topology of complex line arrangements
MSRI-Evans talk, University of California, Berkeley, CA, October 25, 2004 [abstract] - Lie algebras associated to arrangements
Introductory Workshop in Hyperplane Arrangements and Applications, MSRI, Berkeley, CA, August 26, 2004 [video] - Fundamental groups and characteristic varieties
Introductory Workshop in Hyperplane Arrangements and Applications, MSRI, Berkeley, CA, August 24, 2004 [video] - Topology of complex line arrangements (7 lectures)
MSRI Summer Graduate Program on Hyperplane Arrangements and Applications, University of Oregon, Eugene, OR, August 2-13, 2004 - Counting homomorphisms to finite groups
Tapas Seminar, Northeastern University, May 20, 2004 [notes] - What is a hyperplane arrangement?
Student Seminar, Northeastern University, February 10, 2004 - On the decomposability of the holonomy Lie algebra of an arrangement
Special Session on Geometry and Combinatorics, Joint Mathematics Meetings, Phoenix, AZ, January 8, 2004 [abstract]
2003
- Arrangements of hyperplanes and graded Lie algebras
Topology Seminar, University of Lille 1, Villeneuve d’Ascq, France, November 7, 2003 [abstract ] - Graded Lie algebras associated to hyperplane arrangements
GASC Seminar, Northeastern University, October 20, 2003 [abstract] - Systolic inequalities and Massey products
Fifth Congress of Romanian Mathematicians, University of Pitești, Romania, June 25, 2003 - Free abelian covers and systolic inequalities
Analysis and Geometry Seminar, Northeastern University, May 16, 2003 [abstract] - Alexander invariants and lower central series
Topology Seminar, Yale University, April 24, 2003 - Fundamental groups of complex hyperplane arrangements
Special Session on Algebraic and Topological Combinatorics, AMS Spring Eastern Section Meeting, New York, NY, April 12, 2003 [abstract]
2002
- Counting finite-index subgroups and subalgebras
Algebra Seminar, University of Western Ontario, London, ON, Canada, December 6, 2002 - Rational homotopy groups, lower central series, and Koszul algebras
Colloquium, University of Western Ontario, London, ON, Canada, December 5, 2002 [abstract] - Counting finite-index subgroups via p-adic integration
Basic Notions Seminar, Northeastern University, October 31, 2002 - Zeta functions of groups
Basic Notions Seminar, Northeastern University, October 17, 2002 - Chen Lie algebras and combinatorics of arrangements
Special Session on Arrangements of Hyperplanes, AMS Fall Central Section Meeting, Madison, WI, October 13, 2002 [abstract] - Chen ranks of arrangements
Special Session on Algebraic Geometry and Combinatorics, AMS Spring Western Section Meeting, Portland, OR, June 21, 2002 - Fundamental groups of complex hyperplanes arrangements
Topology Seminar, The Ohio State University, Columbus, OH, May 24, 2002 - Virtual jumping loci
Mini-Workshop on Cohomology Jumping Loci, Mathematisches Forshungsinstitut, Oberwolfach, Germany, March 9, 2002 - Torsion in the homology of the Milnor fiber of a multi-arrangement
Mini-Workshop on Cohomology Jumping Loci, Mathematisches Forshungsinstitut, Oberwolfach, Germany, March 6, 2002 - Zeta functions of Orlik-Solomon algebras
Mini-Workshop on Cohomology Jumping Loci, Mathematisches Forshungsinstitut, Oberwolfach, Germany, March 5, 2002 - Lower central series, free resolutions, and homotopy Lie algebras of arrangements
NSF-CBMS Regional Research Conference Arrangements and Mathematical Physics, LSU, Baton Rouge, January 11, 2002. [abstract] [slides]
2001
- Fundamental groups of hyperplane arrangements
Colloquium, University of Rochester, Rochester, NY, November 9, 2001 - Rescaling formulas for rational homotopy groups
Topology Seminar, University of Rochester, Rochester, NY, November 8, 2001 - Lower central series and free resolutions of arrangements
Special Session on Algebraic and Topological Combinatorics, AMS Fall Eastern Section Meeting, Williamstown, MA, October 13, 2001 [abstract] [slides] - Arrangements of hyperplanes and enumerative techniques in group theory (2 lectures)
Topology Seminar, Mathematics Institute of the Romanian Academy, Bucharest, Romania, July 13 and 20, 2001 - Platonic solids
GAANN Seminar, Advanced Scientific Computation Center, Northeastern University, May 1, 2001
2000
- Topology of complex line arrangements
Colloquium, McMaster University, Hamilton, ON, Canada, December 15, 2000 - Fundamental groups of arrangements
Workshop on Arrangements, Forschungsinstitut für Mathematik, ETH Zürich, December 7, 2000 [abstract] - Topology of hyperplane arrangements (Invited address)
A.M.S. Fall Eastern Section Meeting, New York, NY, November 5, 2000 [slides] - The Poincaré conjecture
Basic Notions Seminar, Northeastern University, October 26, 2000 - Counting subgroups of finite index
Graduate Student Seminar, Northeastern University, May 15, 2000 [slides] - Homotopy groups and characteristic varieties
NU Tech Expo 2000, Northeastern University, May 11, 2000 [abstract] - Counting representations onto finite groups, and torsion points on characteristic varieties
Special Session on Enumerative Geometry in Physics, AMS Spring Eastern Section Meeting, Lowell, MA, April 2, 2000 - Cohomological jumping loci and finite-index subgroups
Geometric Analysis Seminar, Technion, Haifa, Israel, March 16, 2000 - Hall invariants and characteristic varieties
Geometry and Topology Seminar, Tel Aviv University, Israel, March 14, 2000 - Braids, links, and hyperplane arrangements
Colloquium, Bar Ilan University, Tel Aviv, Israel, March 8, 2000 [announcement] - Hall invariants and the Alexander stratification of character varieties
Geometric Topology Seminar, Columbia University, February 25, 2000 [announcement]
1999
- Braids, links, and hyperplane arrangements
Colloquium, University of Iowa, December 8, 1999 - Representations to finite groups and homology jumping loci
Topology Seminar, University of Iowa, December 7, 1999 - Topology of hyperplane arrangements
Algebraic Geometry Seminar, University of Illinois at Chicago, December 6, 1999 - Cohomology jumping loci and finite covers
Topology Seminar, Brandeis University, September 28, 1999 - Recognizing surfaces (with Ivo Nikolov)
Poster Session: Connections ’99, Northeastern University, May 10, 1999 [poster] - Cohomology rings, nilpotent quotients, and resonance varieties
GASC Seminar, Northeastern University, April 12, 1999 [abstract]
1998
- Combinatorics and topology of complements of planes in R4
Workshop on Mathematics Related with Arrangements of Hyperplanes, Tokyo Metropolitan University, Tokyo, Japan, July 16, 1998 - On the difference between the fundamental groups of real and complex arrangements
Workshop on Fundamental Groups in Geometry, Mathematisches Forshungsinstitut, Oberwolfach, Germany, May 6, 1998 - Fundamental groups of real and complex arrangements (with Daniel Matei)
Centennial Poster Session, Northeastern University, May 4, 1998 [abstract] [slides] - Characteristic varieties of real and complex arrangements
Combinatorics Seminar, MIT, March 18, 1998 [abstract]
1997
- Homotopy types of subspace arrangements
Topology Seminar, Brandeis University, November 18, 1997 - Topology and combinatorics of arrangements
Colloquium, Laboratoire de Topologie, Université de Bourgogne, Dijon, France, July 2, 1997 - Hyperplane arrangements: Alexander invariants, Chen groups, and characteristic varieties
Differential Geometry Seminar, Institut Élie Cartan, Université Henri Poincaré, Nancy, France, July 1, 1997 - Topology and combinatorics of hyperplane arrangements
Differential Geometry Seminar, Institut Élie Cartan, Université Henri Poincaré, Nancy, France, June 24, 1997 - Hyperplane arrangements and braid groups
Topology-Geometry Seminar, IRMA, Université Louis Pasteur, Strasbourg, France, June 20, 1997 - Topology and combinatorics of hyperplane arrangements
Geometry Seminar, Université de Haute Alsace, Mulhouse, France, June 19, 1997 - Framed manifolds, knots, and homology spheres
Differential Geometry Seminar, Institut Élie Cartan, Université Henri Poincaré, Nancy, France, June 17, 1997 - Alexander invariants of arrangements
Minisymposium on Arrangements of Hyperplanes, Mathematics Ph.D. Centennial Conference, University of Wisconsin, May 20, 1997 [slides] - Braid monodromy of arrangements
Analysis Seminar, Indiana University-Purdue University at Indianapolis, January 24, 1997 - Braid monodromy and Alexander invariants of arrangements
Topology-Geometry Reading Seminar, Indiana University, January 23, 1997 - Hyperplane arrangements and braid groups
Topology Seminar, Indiana University, January 22, 1997
1996
- Gromov norm and bounded cohomology (6 lectures)
Basic Notions Seminar, Northeastern University, September-November 1996 - Combinatorics and topology of complex line arrangements
Combinatorics Seminar, Northeastern University, September 9, 1996 - Topology of hyperplane arrangements (2 talks)
Topology Seminar, Louisiana State University, April 22–23, 1996 - Hyperplane arrangements, braid monodromy, and representations of braid groups
Special Session on Low Dimensional Topology, AMS Meeting, Baton Rouge, LA, April 20, 1996 - Braid monodromy of hyperplane arrangements and representations of braid groups
Special Session and Workshop on Arrangements of Hyperplanes, AMS Central Section Meeting, Iowa City, IA, March 23, 1996
1995
- The braid monodromy of complex hyperplane arrangements
Topology and Geometry Seminar, SUNY at Stony Brook, November 14, 1995 - The Knizhnik–Zamolodchikov equations (5 lectures)
Basic Notions Seminar, Northeastern University, October 19-November 29, 1995 - The braid monodromy of complex hyperplane arrangements
GAS Seminar, Northeastern University, October 10, 1995 - The Seiberg–Witten equations (7 lectures)
Basic Notions Seminar, Northeastern University, January–March 1995
1994
- Chen groups of arrangements
Colloque sur les Arrangements d’Hyperplans, Centre International de Rencontres Mathématiques, Luminy, France, July 7, 1994 - The Chen groups of hyperplane arrangements
GAS Seminar, Northeastern University, June 20, 1994 - Complements of discriminants and braid arrangements
GAS Seminar, Northeastern University, May 23, 1994 - 4-Manifolds (3 lectures)
Basic Notions Seminar, Northeastern University, February 17, 1994
1993
- Alexander modules of hyperplane arrangements
Topology and Group Theory Conference, SUNY at Albany, October 31, 1993 - Alexander modules of arrangements
GAS Seminar, Northeastern University, September 27, 1993 - Complements of hyperplane arrangements
Cech Centennial Homotopy Theory Conference, Northeastern University, June 25, 1993 - Milnor fibrations of homogeneous polynomials
GAS Seminar, Northeastern University, May 10, 1993 - Introduction to quantum field theory and 3-manifold invariants
Analysis-Geometry Seminar, Northeastern University, February 19, 1993
1992
- Representations of mapping class groups
GAS Seminar, Northeastern University, April 17, 1992 - Milnor fibrations of hyperplane arrangements
GAS Seminar, Northeastern University, 1992
1991
- Homology isomorphisms between algebraic groups made discrete
Topology and Group Theory Conference, SUNY at Albany, October 13, 1991 - Homology of Lie groups made discrete
GAS Seminar, Northeastern University, October 4, 1991 - Frame-spinning and non-reflexive knots
Colloquium, SUNY at Binghamton, May 13, 1991 - Knots and framed manifolds
GAS Seminar, Northeastern University, May 10, 1991 - High-dimensional knots with the same complement
Topology Seminar, MIT, February 11, 1991
1990
- Framed manifolds and high-dimensional knots with the same complement
Colloquium, SUNY at Albany, November 11, 1990 - Inequivalent frame-spun knots with the same complement
Topology Seminar, Yale University, May 11, 1990 - Frame-spinning and non-reflexive knots
Topology Seminar, Brandeis University, April 20, 1990
1989
- The second homology of groups of germs of diffeomorphisms
Special Session on Low-dimensional Topology, A.M.S. Fall Eastern Sectional Meeting, Hoboken, NJ, October 22, 1989 - The second homology of jet groups
Geometry Seminar, Northeastern University, October 1989 - Homology spheres, framed bordism, and the plus construction
Topology Seminar, Northeastern University, October 2, 1989
1988
- Iterated spinning and homology spheres
Topology Seminar, Yale University, 1988
1987
- Representing homology classes in rational surfaces
Geometry Seminar, Northeastern University, October 1987 - Fibered knots and spherical space forms
Topology Seminar, Brandeis University, 1987
1986
- The homotopy type of four-dimensional manifolds
Ontario Topology Conference, McMaster University, Hamilton, ON, Canada, October 1986 - Homotopy-type invariants of 4-manifolds
Fall Foliage Topology Conference, Dartmouth College, September 27, 1986 - Homotopy-type invariants of four-dimensional manifolds
Geometry Seminar, Northeastern University, April 1986
1985
- Homology 4-spheres
Topology Seminar, Yale University, October 17, 1985 - Rational homotopy theory of Kähler manifolds (4 lectures)
Rational Homotopy Seminar, Yale University, 1985 - Knots with finite commutator subgroup
Topology Seminar, Yale University, 1985 - Immersed spheres in rational surfaces
Topology Seminar, Yale University, 1985
1984
- Homotopy-type invariants of 4-dimensional knot complements
Topology Seminar, Yale University, 1984 - The homotopy type of 4-dimensional knot complements
Topology Seminar, Columbia University, 1984 - Euler characteristics of groups (3 lectures)
Group Theory Seminar, Columbia University, 1984
1983
- Groups of cohomological dimension one (3 lectures)
Group Theory Seminar, Columbia University, 1983 - The Poincaré conjecture in dimension four (3 lectures)
Topology Seminar, Pennsylvania State University, 1983