====== The Combinatorics Seminar ====== ===== FALL 2012 ===== [[http://www.anybrowser.org/campaign/|Best Viewed With Any Browser]] [[http://www.math.binghamton.edu/dept/directions.html|Directions to the department.]] Organizers: [[laura/|Laura Anderson]], [[swartz/|Eric Swartz]], and [[zaslav/|Thomas Zaslavsky]]. ----

**Tuesday, September 4**\\ Organizational meeting\\ //Time//: 1:15 - 1:45\\ //Room//: LN-2205
**----- Special Announcement -----**
- **[[f12-matroids.html|Weekly Study Seminar on Matroid Theory]]**\\ //Time//: Wed., 3:30 - 4:30, beginning **Wed., Sept. 5**\\ //Room//: LN-2206\\ All are invited. This will be a very elementary introduction to the basics of matroids, based on James Oxley, Matroid Theory, second edition. Zaslavsky hopes to teach a course on matroid theory in the spring; this could be (optional) preparation for it.
**Tuesday, September 11**\\ //Speaker//: Alex Schaefer (Binghamton)\\ //Title//: [[abstract.201209sch|Realizing Directed Graphs by Dice]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
Saturday, September 15\\ **DISCRETE MATHEMATICS DAYS OF THE NORTHEAST**\\ At the Bread Loaf Campus of Middlebury College. [[http://community.middlebury.edu/~jschmitt/discmathdays12.html|Information]].\\ All interested persons are invited. Preregistration is requested so enough lunches will be available.
**Tuesday, September 18**\\ Holiday: No seminar.
**Tuesday, September 25**\\ //Speaker//: Matt Brin (Binghamton)\\ //Title//: [[abstract.201209bri|Groups and Map Colorings]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, October 2**\\ //Speaker//: Simon Joyce (Binghamton)\\ //Title//: [[abstract.201210joy|The Conjectures of R. Thomas on Gene Regulatory Networks]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, October 9**\\ No seminar today; the scheduled talk has been cancelled.
**Tuesday, October 16**\\ //Speaker//: Simon Lepkin (Binghamton)\\ //Title//: [[abstract.201210lep|Extended Gale-Shapley Algorithm for Stable Many-Many Matchings]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, October 23**\\ //Speaker//: Eric Swartz (Binghamton)\\ //Title//: [[abstract.201210swa|Locally 3-Arc-Transitive Covers of Complete Bipartite Graphs]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, October 30**\\ //Speaker//: Ed Swartz (Cornell)\\ //Title//: [[abstract.201210swac|Manifold Complexity and Face Enumeration]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
Saturday, November 3\\ **[[gtday64-announcement.pdf|GRAPH THEORY DAY 64]]**\\ Stevens Institute of Technology, Hoboken, New Jersey
**Tuesday, November 6**\\ //Speaker//: Neil Spalter (Binghamton)\\ //Title//: [[abstract.201211spa|Orthogonal Latin Squares of Order 6]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, November 13**\\ //Speaker//: Alex Schaefer (Binghamton)\\ //Title//: [[abstract.201211sch|Introduction to Phylogenetic Combinatorics]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, November 20**\\ //Speaker//: Kaitlin Reissig (Binghamton)\\ //Title//: [[abstract.201210rei|Stanley's Theorem on Acyclic Orientations and Colorings of Graphs]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, November 27**\\ //Speaker//: Michael Fink (Binghamton)\\ //Title//: [[abstract.201211fin|Network Theory and Signal Processing]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, December 4**\\ //Speaker//: Jackie Kaminski (Binghamton)\\ //Title//: [[abstract.201212kam|Classification of Factored Gain-Graphic Arrangements]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205
**Tuesday, December 11**\\ //Speaker//: Amanda Ruiz (Binghamton)\\ //Title//: [[abstract.201212rui|Realization Spaces of Phased Matroids]]\\ //Time//: 1:15 - 2:15\\ //Room//: LN-2205

Phased matroids are combinatorial objects, recently defined by Anderson and Delucchi, that play the same role for complex vector spaces as oriented matroids do for real vector spaces. A phased matroid is a matroid with additional structure that generalizes orientation.

According to Mnëv's Universality Theorem, for those phased matroids which are complexified oriented matroids, the realization space can be arbitrarily complicated. In contrast, for most other phased matroids, the realization space is remarkably simple. I will focus on the rank-3 case to demonstrate some properties of, and proofs about, phased matroids.

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